HK1170635B - Encapsulated omega-3 fatty acids for baked goods production - Google Patents

Description

Encapsulated omega-3 fatty acids for the preparation of baked goods

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority from co-pending U.S. provisional patent application No.61/184,681 entitled "encapsulated omega-3 fatty acids for use in the preparation of baked goods" filed on 5.6.2009 in the name of Bernhard h.

Technical Field

The present invention relates generally to baked goods, such as bread, containing encapsulated easily oxidizable polyunsaturated fatty acids (PUFAs), and more particularly to baked goods containing encapsulated omega-3 fatty acids, encapsulated fatty acids, and doughs and batters containing encapsulated fatty acids for preparing baked goods, and methods for preparing baked goods in which free fatty acids (e.g., omega-3 fatty acids) are stabilized against oxidation.

Background

The prophylactic and therapeutic effects of PUFAs such as omega-3 fatty acids and their action as anti-inflammatory agents are well established. Recent clinical studies have further indicated that the consumption of sufficient amounts of these polyunsaturated fatty acids may be suitable for interventional therapy in animals and humans suffering from rheumatoid arthritis. Dietary sources of PUFAs (e.g., omega-3 fatty acids) are found primarily in foods from the ocean, such as seaweed and fish. However, in most populations the nutritional benefits of PUFA compounds are not recognized due to the low consumption of fish and dietary algae. In keeping with the current allowances of the U.S. food and drug administration for health claims related to the ingestion of omega-3 fatty acids to prevent heart disease, there is an increased interest in fortifying food products with these components. One of the major problems hindering the incorporation of PUFA oils into processed foods is the high degree of unsaturation of such oils, their sensitivity to oxidation and the consequent deterioration in the taste and aroma of the oils.

The sensitivity of PUFA oils to oxidation generally limits their unprotected application to low temperature, short shelf life foods, such as yogurt or frozen beverages, such as orange juice and milk. For long shelf life dry foods such as cereal or oat bar cookies, it is often necessary to encapsulate omega-3 oil to protect against oxidation. Most commercial PUFA capsule products are spray-dried powders, which often have unacceptable sensory attributes. In addition, products that can show bulk stability often fail application studies after 2 or 3 weeks accelerated shelf life testing at 55 ℃, which corresponds approximately to 6 or 9 months of stability at room temperature, respectively.

Encapsulation of PUFA oil in small pellets can be used to improve oxidation and sensory stability in accelerated storage tests at 55 ℃ to 4 weeks or more, which corresponds to about 1 year or more at room temperature, which is a desirable long shelf life for ready-to-eat cereal and oat bar biscuits. However, encapsulated PUFA pellets still require careful handling and cannot be treated by overheating, excessive wetting or high shear forces during food processing. In addition, dry pellets may not be compatible with the texture of certain types of food products.

In addition, when encapsulating a component in a matrix, the matrix material is typically heated to a temperature high enough to form a plasticized mass that facilitates intercalation or encapsulation of the component. Upon cooling, the matrix material hardens or solidifies, protecting the encapsulant from undesirable or premature reactions. Grinding of the solidified or glassy product to achieve the desired particle size for incorporation into a food or beverage generally results in the formation of irregularly shaped chips and rough surfaces. Irregularly shaped fragments and cracked surfaces can cause uneven release of the encapsulant, increased diffusion of the liquid encapsulant, and increased penetration of oxygen and water, which can have deleterious effects on sensitive encapsulants, such as easily oxidized components. The incorporation of water-soluble antioxidants (e.g. acidic antioxidants) and fluid reaction media (e.g. water or glycerol) for improving antioxidant activity into the dry matrix material may result in water activities that are not storage stable, adversely affect the desired texture, adversely affect the release properties of the matrix, or promote dissolution of the encapsulated PUFA pellets during dough or batter mixing.

Soft pellets containing encapsulated PUFAs and an acidic antioxidant and a motivating liquid (e.g., glycerin) provide long-term antioxidant activity and good adhesion for topical application to cereal substrates such as corn chips, puffs, or pellets. However, the small, soft nature of the pellets has been found to produce an unexpected effect on their use in bread and other baked goods. It has been found that when soft pellets of encapsulated PUFAs are incorporated into a dough or batter for the preparation of baked goods, such as bread, the pellets dissolve rapidly in the dough or batter during mixing of the components to obtain a homogeneous dough or batter, during kneading of the dough and during baking. During the dough or batter preparation process, the moisture of the dough or batter and the shear and mixing forces applied during mixing and/or kneading cause moisture or water to penetrate the omega-3 pellets, making the pellets softer and more spreadable until they completely disappear and become incorporated into the dough and batter. With complete dissolution, the physical and chemical protection of the omega-3 oil initially provided by the encapsulating matrix is lost, resulting in rapid deterioration and organoleptic damage due to oxidation during storage of the baked food product (e.g., bread), which is originally targeted at room temperature for 14 days after baking. While increasing the particle size allows a portion of the larger pellets to remain during dough mixing, the dissolved portion produces an undesirable fishy rancid taste and odor in the baked product. In addition, large pellets, which are readily visible to the naked eye, can impair the desired cellular uniform structure or can be inconsistent with the soft texture and desirable mouth feel of baked goods such as breads, cakes and muffins.

The present invention provides encapsulated oil pellets containing readily oxidizable polyunsaturated fatty acids, such as omega-3 oils, incorporated into a starch and protein matrix, which pellets can be used in, or processed or incorporated into or added to baked food dough and batters, baked goods (e.g., bread, snacks, cookies, rolls, crackers, biscuits, cakes, muffins, and bread sticks) without smearing or dissolving in the dough, batter, or baked goods to impart antioxidant stability to the food products for extended shelf life, resistance to fish spoilage, unpleasant taste, and unpleasant odor.

Summary of The Invention

In a first aspect of the invention, an encapsulated product for baked goods that can be incorporated into baked goods dough or batter without smearing or dissolving in the dough or batter comprises oil droplets comprising at least one polyunsaturated fatty acid, a protein-containing film-forming component coating the oil droplets, a matrix material encapsulating the coated oil droplets, a liquid plasticizer plasticizing the matrix material, and an acidic antioxidant dispersed throughout the plasticized matrix material. The matrix material comprises a starch component and a protein component, wherein the amount of protein in the matrix material is from about 35 to about 75 weight percent, preferably from about 45 to about 65 weight percent, based on the weight of the matrix material. The protein content of the encapsulated product is from about 25 to 65% by weight, preferably from about 40 to 60% by weight, based on the weight of the encapsulated product. The protein component stiffens the encapsulated product, preventing significant smearing and dissolution of the encapsulated product and release of oil during mixing of the encapsulated product with the baked product dough or batter and in baked goods. The starch component helps to avoid a rubbery consistency and texture and improves extrudability.

In addition, the acidic antioxidant is distributed throughout the matrix material to help prevent oxidation of the at least one polyunsaturated fatty acid and the development of fishy spoilage or unpleasant tastes and odors. The amount of acidic antioxidant may typically be from about 0.5 to about 10% by weight, preferably from about 1 to about 5% by weight, most preferably from about 2 to about 4% by weight, based on the weight of the encapsulated product. The amount of oil may be from about 5 to 20% by weight based on the weight of the encapsulated product. The acidic antioxidant may optionally be mobilized within the matrix using a liquid polyol in an amount that does not excessively soften the encapsulated product such that smearing or dissolution of the encapsulated product occurs during dough or batter mixing, preparation and baking. The encapsulated product may be in the form of discrete particles or pellets having a diameter of about 0.2 to 3.0 mm, preferably about 0.4 to 0.9 mm. In an embodiment of the invention, the encapsulated product has a storage or shelf stability of at least about 6 months, preferably at least 12 months, under nitrogen purged ambient or refrigerated conditions.

In another aspect of the invention, baked food dough or batter, baked food mixes, baked food kits, packages and baked goods containing the encapsulated product are provided. Examples of baked goods that may comprise encapsulated products are bread, biscuits, rolls, buns, cakes, muffins, breadsticks, pretzels, pizzas, cookies, crackers, and snacks. Even though vigorous mixing and kneading may be used, such as in the case of bread dough manufacture, and high water content dough or batter may be used, the encapsulated product is unexpectedly not smeared or dissolved in the dough or batter or in the baked product. In embodiments of the invention, the encapsulated product may be included in a baked food mix, such as in bread mixes, cake mixes, cookie mixes, muffin mixes, and baking flours. In embodiments of the invention, the encapsulated products of the invention may be packaged in nitrogen purged pouches, pouches or other packaging of highly moisture and/or oxygen barrier materials. The package of the encapsulated product may be sold as such or may be included in a baked good kit with other packages containing a premix of the flour-containing baked food ingredient.

In another aspect of the invention, a method of encapsulating a polyunsaturated fatty acid-containing product for incorporation into a baked good without significant smearing and dissolution of the encapsulated product upon mixing the encapsulated product in the baked good dough or batter comprises: forming an oil-in-water emulsion comprising at least one polyunsaturated fatty acid and a protein-containing film-forming component. Mixing the oil-in-water emulsion with a matrix material, a liquid plasticizer for plasticizing the matrix material, and an acidic antioxidant for preventing oxidation of the at least one polyunsaturated fatty acid. The matrix material comprises a starch component and a protein component, the amount of protein in the matrix material being from about 35 to about 75% by weight, preferably from about 45 to about 65% by weight, based on the weight of the matrix material. Mixing is carried out in order to obtain a formable mixture, wherein the matrix material comprises an acidic antioxidant and encapsulates the oil-in-water emulsion. The formable mixture is formed into a tablet form and the tablet is dried to provide a dry tablet of encapsulated product having a protein content of from about 25% to about 65% by weight, preferably from about 40% to about 60% by weight, based on the weight of the encapsulated product. In an embodiment of the invention, the starch component and the protein component may be pre-blended to provide a matrix material, and the matrix material may be mixed with the acidic antioxidant, the emulsion, and the plasticizer to at least substantially plasticize the matrix material and to substantially uniformly distribute the antioxidant throughout the matrix material.

In embodiments of the invention, when using commercial mixing processes and/or low water content doughs (e.g., bread dough and cookie dough prepared on commercial scale dough mixing and kneading equipment), the amount of protein in the matrix is from about 25 to 77.5% by weight, preferably from about 30 to 77.5% by weight, more preferably from about 30 to 65% by weight, based on the weight of the matrix material. Additionally, when mixing is performed with low moisture content dough (e.g., cookie dough), and/or when commercial scale mixing methods and equipment are used, the protein content of the encapsulated product is from about 15% to about 65% by weight, preferably from about 20% to about 65% by weight, and more preferably from about 20% to about 55% by weight, based on the weight of the encapsulated product.

In yet another aspect of the invention, a method of incorporating polyunsaturated fatty acid-containing oils into baked goods comprises mixing the encapsulated product with baked good dough or batter ingredients comprising flour and water to produce a dough or batter in which the encapsulated product does not significantly smear and dissolve. The dough or batter may be baked to obtain baked goods such as bread, cookies, rolls, buns, cakes, muffins, loaves, pretzels, pizzas, cookies, crackers and snacks, encapsulated products that do not significantly smear and dissolve in the baked goods. In an embodiment of the invention, the omega-3 fatty acid concentration, e.g., docosahexaenoic acid (DHA) concentration, of the baked good (e.g., bread) is at least about 10 mg per serving size, preferably at least about 16 mg per serving size, most preferably at least about 32 mg per serving size, and the shelf stability after baking is the same or longer than the shelf life of a baked good that does not incorporate polyunsaturated fatty acids.

Brief Description of Drawings

The invention is further illustrated with reference to the accompanying drawings, in which:

figure 1 shows the relationship between particle size, protein content and smearing or dissolution of the encapsulated product when it is mixed with bread dough ingredients to give a bread dough.

Figure 2 shows a superimposed graph of the organoleptic and physical stability of the pellets versus the content of glycerol by weight of the encapsulated or final product and the content of wheat protein in the matrix by weight of the dry matrix.

Detailed Description

The present invention relates generally to baked goods, such as bread, containing polyunsaturated fatty acids that are readily oxidized, and more particularly to baked goods containing omega-3 fatty acids and a method of making the baked goods in which free fatty acids, such as omega-3 fatty acids, are stabilized against oxidation, fishy spoilage, or off-flavors and off-flavors. The use of an encapsulated product comprising readily oxidizable polyunsaturated fatty acids encapsulated in a matrix material containing a critical amount of a protein component and a starch component unexpectedly avoids significant smearing and dissolution of the encapsulated product in the dough or batter during dough or batter production and baking which can lead to oxidative instability and fishy spoilage and results in a non-rubbery texture and mouthfeel compatible with the texture of baked goods. In embodiments of the invention, the shelf life of the baked product after baking can be the same or longer than a baked product that does not incorporate polyunsaturated fatty acids. For example, the shelf life of bread, rolls, buns, muffins, and other high moisture soft baked goods can typically be about 14 days after baking. Similar baked goods, such as bread, prepared according to the present invention may have a shelf life of at least 14 days after baking, even if they contain high amounts of easily oxidizable polyunsaturated fatty acids. In other embodiments of the invention, a low moisture content product, such as a crispy cookie or snack, has a shelf life of at least about 6 months after baking despite the high content of readily oxidizable polyunsaturated fatty acids in the baked product.

An encapsulated product for baked goods which can be incorporated into a dough or batter for baked goods without significant smearing or dissolution of the encapsulated product in the dough or batter comprises oil droplets comprising at least one polyunsaturated fatty acid (e.g. an omega-3 fatty acid) and a film-forming component comprising a protein coating the oil droplets. The matrix material of the present invention encapsulates the encapsulated oil droplets, and a liquid plasticizer plasticizes the matrix material. In addition, an acidic antioxidant is dispersed throughout the plasticized matrix material. The matrix material comprises a starch component and a protein component, wherein when the mixing is performed in a retail-scale bread making machine, typically using longer mixing times, weaker mixing intensity and higher moisture content dough, the amount of protein in the matrix material is critically about 35-75% by weight, preferably about 45-65% by weight, based on the weight of the matrix material. When the mixing is carried out with a bread machine of retail size, the protein content of the encapsulated product is critically about 25-65%, preferably about 40-60% by weight of the encapsulated product.

In a further experiment at scale up, it was found that lower amounts of protein and higher amounts of glycerol could be used: 1) when commercial-scale bread making equipment and processes, particularly commercial dough mixing and kneading equipment, are used, shorter mixing times, more intensive mixing and lower moisture levels are typically used, and/or 2) the dough used is typically low in moisture, such as cookie dough. It has been found that when commercial mixing processes and/or low moisture content doughs are used, the amount of protein in the matrix is critically from about 25 to 77.5% by weight, preferably from about 30 to 77.5% by weight, more preferably from about 30 to 65% by weight, based on the weight of the matrix. In addition, when mixing is carried out with low water content dough and/or with commercial scale mixing methods and equipment, the protein content of the encapsulated product is critically from about 15 to 65%, preferably from about 20 to 65%, more preferably from about 20 to 55%, by weight of the encapsulated product.

For example, in embodiments of the present invention, to prepare a low water content dough (e.g., cookie dough) and/or prepare a dough on a commercial scale using commercial mixing equipment and methods, such as a bread dough, the amount of protein used in the matrix can range from about 25 to 35% by weight based on the weight of the matrix material; the protein content of the encapsulated product or end product may be from about 15% to about 25% by weight based on the weight of the encapsulated product or end product.

The protein component hardens the encapsulated product and prevents significant smearing and dissolution and oil release of the encapsulated product during mixing in the baked good dough or batter and in the baked good. The starch component helps to avoid rubbery consistency and texture due to too much protein and improves extrudability. The starch component reduces the consistency due to the protein component, which makes extrusion or machining of the plasticized mass difficult or impossible, especially when small pellets are prepared using small extrusion die orifices. The acidic antioxidant is distributed throughout the matrix material and helps to prevent oxidation of the at least one polyunsaturated fatty acid and fishy spoilage or development of unpleasant tastes and odors. The acidic antioxidant may optionally be mobilized in the matrix using a liquid polyol in an amount that does not excessively soften the encapsulated product such that the encapsulated product smears or dissolves during dough or batter mixing and preparation and during baking.

The encapsulated product exhibits extended storage stability during storage prior to incorporation into the dough or batter, as well as after incorporation into the dough or batter, and after the dough or batter is baked into a baked good, without significant oxidation of the readily oxidizable polyunsaturated fatty acids (e.g., omega-3 fatty acids). In embodiments of the invention, the encapsulated product may have a shelf or shelf stability of at least about 6 months, preferably at least 12 months, under nitrogen purged ambient or refrigerated conditions. Such encapsulated products may be included in baked food mixes such as bread mixes, cake mixes, cookie mixes, muffin mixes, and baking flours. In embodiments of the invention, such encapsulated products of the invention may be packaged in nitrogen purged, high moisture and/or oxygen resistant bags or pouch-like materials or other bags. The packaging of the encapsulated product may be sold as such or may be included in a baked food product kit or mix with other packaging including a flour-containing baked food ingredient premix. Examples of baked products that may comprise encapsulated products are bread, biscuits, rolls, buns, cakes, muffins, breadsticks, pretzels, pizzas, cookies, crackers, and snacks.

Readily oxidizable oils that may be used in the present invention include, for example, castor oil, algae-based or seaweed-derived oils, linseed or flaxseed oil, fish oils, seed oils, oils derived from microorganisms, or any other oil containing polyunsaturated fatty acids (PUFAs), such as omega-3 fatty acids, eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), docosapentaenoic acid, and linolenic acid, alpha-linolenic acid, conjugated linolenic acid, gamma linolenic acid, and omega-6 fatty acids. In an embodiment of the invention, the easily oxidizable oil may be those obtained from plants that have been genetically modified to contain polyunsaturated fatty acids or have been increased in amounts to levels higher than the levels found in oils of plants that have not been genetically modified, such as soybean oil, sunflower oil, canola oil, rapeseed oil, or corn oil. The oil or fruit product may also include other readily oxidizable oils such as fat soluble vitamins (e.g., vitamins A, D, E and K), cod liver oil, flavorants, essential oils, flavorants, extracts containing active ingredients (e.g., chlorophyll or herbal extracts), plant steroids, oil soluble agricultural, pharmaceutical and other bioactive components, and mixtures thereof. In an embodiment of the invention, the readily oxidizable oil may be any oil derived from any plant, animal, marine organism or microorganism that contains a substantial amount, e.g., at least 5% by weight, of the readily oxidizable component. Examples of oils that may contain a significant amount of readily oxidizable components are oils derived from soybean and corn, sunflower oil, rapeseed oil, walnut oil, wheat germ oil, canola oil, krill oil, oils derived from yeast, blackcurrant seed oil, sea buckthorn oil, cranberry seed oil, and grape seed oil. The omega-3 fatty acid content (DHA, EPA) of the purified fish oil may be, for example, about 25-49% by weight. The omega-3 fatty acid content of linseed oil may be as high as about 71% by weight.

In embodiments of the invention, the oxidizable oil (e.g., omega-3 oil) can be included in an amount of up to about 25% by weight, for example about 5-20% by weight, preferably about 8% by weight. Additionally, in embodiments of the invention, the amount of oil used may provide the minimum daily requirement for polyunsaturated fatty acids (e.g., omega-3 fatty acids) recommended by the U.S. Food and Drug Administration (FDA), or a substantial percentage of the recommended daily amount (DV), or some amount or concentration of omega-3 oil in the encapsulated product required to meet certain food regulations for various baked goods. For example, in embodiments of the invention, the omega-3 fatty acid concentration of a baked good (e.g., bread), such as docosahexaenoic acid (DHA), may be at least about 10 mg per serving, preferably at least about 16 mg per serving, and most preferably at least about 32 mg per serving. In a preferred embodiment of the invention, the encapsulated product may contain sufficient oil to provide bread or other baked goods with a docosahexaenoic acid (DHA) concentration of at least about 32 mg per 50 g serving.

The matrix material of the present invention is plastic and comprises a protein component and a starch component. The protein component may be a vegetable protein, a milk protein, an animal protein, a protein concentrate, and mixtures thereof. Examples of protein components which may be used are wheat protein isolate, vital wheat gluten, gelatin, casein, caseinate (e.g. sodium, potassium or calcium caseinate), soy protein isolate, whey protein isolate, and mixtures thereof. The protein content of the protein component is generally at least about 60% by weight, preferably at least about 70% by weight, and most preferably at least about 85% by weight, based on the weight of the protein component. One protein component preferred for use in the present invention is a wheat protein isolate, such as ARISE 5000 by MPG Ingredients, Inc., Atchison, Kansas. ARISE 5000 has a protein content of greater than 90 wt% (N.times.6.25, d.b.), an ash content of about 1 wt%, is more extensible, less elastic (gluten-like), has an acidic pH of hydration and a pH of about 4, and has been treated with sulfite to a residual sulfite content of about 45 ppm.

The starch component of the moldable base material can be a high gluten content flour, durum or semolina, pregelatinized or modified starch, corn flour, wheat flour, rice flour, barley flour, oat flour, rye flour, heat-treated flour (e.g., heat-treated wheat flour), and mixtures thereof. The modified or pregelatinized starch may be derived from corn, wheat, rice, potato, tapioca, or high amylose starch. Sources of starch that may be used include flours derived from grains such as corn, wheat, durum wheat, rice, barley, oats or rye and mixtures thereof. Preferred starch components for use in the present invention are durum wheat flour and semolina. The starch content of the moldable starch component is generally at least about 75% by weight, preferably at least about 80% by weight, and most preferably at least about 85% by weight, based on the weight of the starch component.

Durum wheat products or ingredients that may be used in the present invention include durum wheat middlings, durum semolina durum semolina and mixtures thereof. Durum wheat flour is preferred. Durum wheat middlings are purified or separated semolina of durum wheat, which are prepared by grinding and sieving clean durum wheat to a fineness such that when tested according to the method specified in 21 CFR' 137.300(b) (2) it passes through the U.S. sieve No. 20 but not more than 3% of the U.S. sieve No. 100. The meal is free of bran or bran and germ to the extent that the ash content (calculated on a moisture free basis) does not exceed 0.92%. Durum semolina products are semolina to which flour is added so that about 7% passes through a U.S. No. 100 sieve. The durum wheat flour passes through no less than 98% of U.S. No. 70 sieve.

In an embodiment of the invention, the amount of mouldable matrix material, or the total amount of protein component and starch component, may be from about 60 to 85% by weight, preferably from about 65 to 80% by weight, based on the weight of the encapsulated product.

In embodiments of the invention, a substantially non-plastic matrix component may be used to facilitate processing in an amount that does not excessively soften the encapsulated product, such as to cause smearing or dissolution of the encapsulated product between dough or batter mixing and preparation bases and during baking. Such a substantially non-moldable matrix material may comprise substantially non-gelatinized starch, such as raw or native starch, and carbohydrates having a lower molecular weight than starch, fillers, fibers or other inert materials, such as cellulose, fibers or hemicellulose. Sources of starch that may be used include starches derived from grains such as corn, wheat, durum wheat, rice, barley, oats or rye, and mixtures thereof.

Examples of acidic antioxidants or proton donating antioxidants that can be used in effective amounts in the matrix material are organic acids such as L-cysteine, acetic acid, tartaric acid, lactic acid, malic acid, citric acid, fumaric acid, propionic acid, tannic acid, ascorbic acid, erythorbic acid and erythronic acid, tocopherol, catechins, their salts, isomers, derivatives, and mixtures thereof. Examples of salts which may be used are alkaline earth metal salts and alkali metal salts, such as the calcium, potassium and sodium salts of ascorbic acid, erythorbic acid and L-cysteine, and phenolates. Examples of derivatives include anhydrides, esters, amides, and lipophilic acids. Preferred acidic antioxidants for use in the matrix material are organic acids such as citric acid, ascorbic acid and erythorbic acid, most preferred is erythorbic acid or ascorbic acid. In embodiments, the antioxidant may be added to the matrix material, to the plasticizer mixed with the matrix material, or to the plasticizer during emulsion preparation and formation.

The amount of acidic antioxidant may generally be from about 0.5 to about 10% by weight, preferably from about 1 to about 5% by weight, most preferably from about 2 to about 4% by weight, based on the weight of the encapsulated product.

The plasticizer or combination of plasticizers used to plasticize the plasticized matrix material facilitates the mixing, dispersion and mobilization of the acidic antioxidant throughout the matrix material. Water is a preferred plasticizer for use in the present invention. The plasticizer may comprise at least one liquid that solubilizes the acidic antioxidant and retains a sufficient amount in the pellet after drying to prevent crystallization of the acidic antioxidant and to provide motility for the acidic antioxidant in the dried pellet. It is envisaged that the mobility provided should be such that the acidic antioxidant is able to react with any ambient oxygen that enters the interior of the pellet or the matrix material so as to prevent oxygen from penetrating into the interior of the coated oil droplets. In addition, the plasticizer should preferably keep the acidic antioxidant solubilized and prevent substantial crystallization within the dried pellets. The mobility should be such that the acidic antioxidant donates a proton to terminate any free radicals from the fatty acid and/or react with any off-flavoured amines released by the fish oil. Examples of mobile plasticizers that may be used with the acidic antioxidants are water, polyols or glycols, such as glycerol, propylene glycol and polyethylene glycol, sugar alcohols, such as sorbitol, mono-and disaccharides, such as fructose and dextrose, and mixtures thereof.

Water may be used to plasticize the matrix material and solubilize the acidic antioxidant, while drying the pellets to achieve a shelf-stable water activity of less than about 0.7 typically results in substantial crystallization and immobilization of the acidic antioxidant in the pellets. However, it has been found that the use of large amounts of plasticizer softens the encapsulated product, promoting smearing or dissolution of the encapsulated particles, which may not be required in high protein content encapsulated products. It is believed that the use of high levels of protein prevents water and oxygen from approaching the readily oxidizable polyunsaturated fatty acids in large quantities. Thus, water or an aqueous solution capable of forming a dough, such as a juice, may be used as a plasticizer in the matrix to facilitate mixing and initial dispersion and homogenization of the antioxidant. However, a less volatile liquid plasticizer or softener (e.g., polyol) may also optionally be used to achieve mobility of the acidic antioxidant in the base material in the final pellet in an amount that does not excessively soften the encapsulated product so as to cause smearing or dissolution of the encapsulated product during dough or batter mixing and preparation and during baking. Increasing the amount of glycerin is also desirable to improve the organoleptic and chemical or oxidative stability of the pellets, but can result in reduced physical stability of the pellets or smearing or dissolution in dough with high moisture content (e.g., bread dough). At higher glycerol levels, physical stability can be increased by increasing the protein content in the matrix and in the encapsulated product. For example, at least one liquid polyol may optionally be used to provide mobility in the plasticized matrix material to the acidic antioxidant in an amount less than or equal to about 20% by weight, such as from about 5 to 20% by weight, preferably less than about 15% by weight, based on the weight of the encapsulated product, for low water baked food dough (e.g., cookie dough). For higher water content doughs, such as bread doughs, the at least one polyol optionally used may be present in an amount of less than about 10% by weight, such as less than about 5% by weight, preferably from about 1.0 to about 7.5% by weight, based on the weight of the encapsulated product.

The water or aqueous solution used as plasticizer for the matrix material may be mixed with an optional non-aqueous plasticizer or softener, or may be added separately to the matrix material. The water used to form the oil-in-water emulsion also serves to plasticize the plastic portion of the matrix material.

In embodiments of the invention, release rate controlling agents may be added to the mixtures of the invention, including components that may manipulate, control or influence the flow, diffusion or distribution of the aqueous or non-aqueous based ingredients into and within the final product particles. These additional ingredients or components used to control the release rate of the encapsulate can be hydrophobic agents such as fats, oils, waxes, fatty acids, or emulsifiers that increase the hydrophobicity of the matrix. The increased hydrophobicity helps to prevent or retard the penetration of water or stomach acid into the matrix.

In embodiments of the invention, one or more flavorants, such as fruit flavors or vanilla or vanillin or other taste modulating components, such as cocoa or cinnamon powder, may be added to the base material to help mask the off-tastes and malodors. Exemplary amounts of such components or flavorants that can be used can be up to about 20% by weight, such as up to about 5% by weight, based on the weight of the matrix material.

In embodiments of the invention, titanium dioxide or zinc oxide may be added to the matrix material to modify the shape of the pellets and to lighten the color of the pellets as a whitening agent. Exemplary amounts of whitening agent that can be used can be up to about 10% by weight of the matrix material.

The preparation method of the pellet comprises the following steps: the water content of the stabilized emulsion is first reduced so that the film-forming component forms a film around the oil droplets and encapsulates the encapsulate. After homogenization, the water content of the emulsion may be reduced by mixing the emulsion with a plasticized matrix material, thereby encapsulating the encapsulated oil droplets within the plasticized matrix material. In embodiments of the invention, the pH of the pellet may be from about 2.5 to about 8.

Improved dispersion is obtained by pre-emulsifying the encapsulate and achieving encapsulation of the active, sensitive encapsulate material in separate storage stable particles. The encapsulate is incorporated into or constitutes the oil phase of an oil-in-water emulsion. The oil-in-water emulsion containing the encapsulates is mixed with a plasticizable matrix material to encapsulate the encapsulates within the matrix material. The use of a matrix material that can be plasticized by the emulsion or the water component of the emulsion results in the encapsulates being encapsulated within the plasticized matrix material. The encapsulate or sensitive active ingredient may be emulsified directly with water or an aqueous liquid plasticizer.

In embodiments of the invention, an aqueous component, such as water or an acidic aqueous solution (e.g., 0.2N aqueous acetic acid), may be mixed with a film-forming component (e.g., a protein) to provide an aqueous solution. The film-forming component helps stabilize the emulsion, maintain oil droplet size, inhibit diffusion of the oil component and encapsulates to the surface of the particle or pellet, and inhibit rancidity-causing oxygen from contacting the oil component.

The film-forming component content, or protein content, of the aqueous solution (e.g., aqueous protein solution) may be from about 1 to 50% by weight, preferably from about 5 to 25% by weight, and most preferably from about 8 to 15% by weight, based on the total weight of the aqueous solution component (e.g., water) and the film-forming component (e.g., protein).

In embodiments of the invention, the film-forming component is water-soluble and may contain hydrophobic or lipophilic moieties, such as film-forming proteins, which may then concentrate at the interface of oil and water. Film-forming components that may be used include, but are not limited to: a protein; a carbohydrate; hydrocolloids such as alginates, carrageenans, and gums; starches, such as modified starches and starch derivatives; or mixtures thereof. Protein is the preferred film-forming component for emulsification. Examples of proteins that may be used are one or more vegetable proteins, milk proteins, animal proteins or protein concentrates, such as proteins derived from milk, whey, corn, wheat, soy or other vegetable or animal sources. Preferred proteins for use in the present invention are milk proteins, such as caseinate and whey protein isolates, and wheat protein isolates, such as gluten. Caseinates such as sodium, potassium, calcium and ammonium caseinate are the most preferred proteins for the preparation of the coated oil droplets.

Caseinate is a readily soluble protein that forms an aqueous phase with a lower viscosity than that obtained with other proteins such as whey protein isolate. The lower viscosity facilitates emulsification and homogenization with the oil phase and results in small oil droplet size, and unexpectedly superior microencapsulation efficiency.

The Microencapsulation Efficiency (ME) can be calculated as follows:

ME = [ (total oil amount-free oil)/total oil amount ] × 100 [% ]

Quantitative determination of total oil content in samples can be accomplished by acidic hydrolysis followed by extraction according to the Weibull-Stoldt method. Free, accessible or unencapsulated oil in extruded pellets can be determined using methods modified according to the following references:

. A sample of about 1 g of total oil (e.g., 7 g of extruded pellets having an oil content of about 15%) can be transferred to 100 mL of petroleum ether (boiling point: 60-80 ℃) and stirred with a magnetic stir bar at ambient temperature for exactly 15 minutes. After the filtration (Schleicher)&Schuell 595), the filtrate is transferred to a soxhlet extraction unit and the solvent can be evaporated at 80 ℃. The oil residue received is dried in a drying oven (Herae)us 6060, Kendro Laboratory Products, Hanau, Germany) was dried to constant weight (or minimum weight) at 105 ℃ and quantified by weight (about 1 hour). Under the conditions of the previous method, the free oil has been completely removed from the pellets after 15 minutes. Increasing the stirring time to 60 minutes did not cause significant changes. The use of petroleum ether results in the highest free oil content compared to other solvents such as alcohols, ethers, water and/or mixtures thereof. In embodiments of the invention, the microencapsulation efficiency may be greater than about 85%, preferably greater than about 90%.

The protein may be at least substantially or completely hydrated and denatured prior to mixing with the oil component to avoid clumping and facilitate subsequent pumping through the homogenizer. To achieve hydration, the solution may be prepared and stored under refrigerated conditions immediately prior to use or up to one day prior to use, so that any foam produced by mixing is allowed to settle.

Proteins, such as Whey Protein Isolate (WPI), may either remain in their native form or be denatured prior to emulsification with fish oil. Denaturation can be accomplished by heating the dispersed WPI solution to about 80-90 ℃ for 30 minutes. The denatured WPI solution appears to form a better film than the native WPI solution and may improve the stability of the final encapsulated oil. In each case, the whey protein isolate may act as an emulsifier in the final emulsion with the oil. In addition, it is desirable to fully hydrate the WPI solution (natural or denatured) and cool it under freezing conditions (e.g. about 40 ° f) prior to use.

In an embodiment of the invention, the emulsion may be prepared as follows: one or more optional ingredients are mixed with an aqueous film-forming component solution, such as an aqueous protein solution, using a high shear mixer, such as an Ultra-Turrax Rotosolver high shear mixer or other mixer with sufficient shear. These optional ingredients include film softening ingredients or plasticizers, non-acidic antioxidants, flavorants and emulsifiers in amounts that do not adversely affect the viscosity required for emulsification and homogenization, as well as achieving small oil droplet sizes and stable emulsions. When an easily oxidizable encapsulate such as an omega-3 fatty acid is encapsulated, the mixing of the optional components with the emulsion is preferably carried out under an at least substantially oxygen-free atmosphere, for example under a nitrogen blanket or an inert gas blanket. Preferably preventing and/or reducing exposure to oxygen, a nitrogen blanket may be applied at a later site when the fish oil is directly exposed to the atmosphere.

Optionally, a film-softening component or plasticizer may be added during the emulsification step to reduce the brittleness and prevent cracking of the film formed from the film-forming component, including mono-and disaccharides, such as sucrose and fructose, and polyols (such as glycerol) and polyethylene glycols in amounts that do not cause significant smearing or dissolution of the pellets.

For the encapsulation of readily oxidizable components such as polyunsaturated fatty acids (such as omega-3 fatty acids in oils derived from fish, seaweed, flax, seeds, microorganisms or other sources), the emulsion is preferably prepared in a substantially oxygen-free atmosphere, for example under a nitrogen blanket, and optionally a non-acidic antioxidant or an acidic antioxidant may be added to the aqueous or oil phase during the emulsification stage. Examples of antioxidants that may be used are L-cysteine and its salts, ascorbic acid and its salts, erythorbic acid and its salts, tocopherols, catechins, TBHQ (e.g. Grindox 204), phenolic compounds, natural antioxidants, such as grape seed extract containing antioxidant phenolic compounds, and nut fibers, such as almond fibers, and mixtures thereof. TBHQ may or may not be present in the oil used as the feedstock, but may, if present, be additionally added to the oil prior to emulsification. For example, TBHQ may be added to the oil in an amount of about 10 to 1200 ppm, more preferably about 600 to 1000 ppm, based on the weight of the oil component. The concentration of mixed tocopherols in the oil can be about 10-1000 ppm. In embodiments of the invention, the optional antioxidant employed in the emulsion stage may be from about 10 to 10,000 ppm, for example from about 50 to 1000 ppm by weight, or about 100 ppm by weight based on the weight of the oil component.

An acidic antioxidant, a non-acidic antioxidant, or a film softening component or plasticizer may optionally be used in the emulsion. In embodiments, the antioxidant optionally used in the emulsion may be the same or different than the antioxidant used in the matrix. In an embodiment of the invention, it is preferred to use only acidic antioxidants in the matrix material. The acidic antioxidant in the matrix material acts to prevent the oxidizable component of the coated oil droplets from being oxidized. In addition, the optional mobilizing plasticizer migrates to the film-forming component in the matrix material and helps reduce its brittleness.

In embodiments, an acidic antioxidant may be added to the matrix material to avoid possible deleterious interactions between the protein and the acidic antioxidant. In other embodiments of the invention, this detrimental interaction can be overcome by adding a protein (e.g., sodium caseinate) to an already acidified medium, wherein the pH of the medium is above or below the isoelectric point of the protein (e.g., about 4.4-4.6 for sodium caseinate).

Any compatible flavorant can be added to the oil phase to mask off-tastes and unpleasant odors in the oil and to help chemically stabilize the oil phase. Flavorants may be added in an amount of about 0.1 to about 25% by weight, for example about 1 to about 25% by weight, preferably about 0.5 to about 15% by weight, for example about 10 to about 15% by weight, more preferably about 1 to about 5% by weight, for example about 2 to about 5% by weight, based on the weight of the oil phase.

The oil and water phase components may be mixed in a high shear mixer, for example in an Ultra-Turrax Rotosolver, for about 10 minutes prior to high pressure multi-stage homogenisation.

Once all the ingredients used to prepare the emulsion have been mixed, the resulting emulsion or composition of ingredients can be run through a homogenizer. The total stage pressure of the homogenizer may be about 1 to 30,000 psig (about 7 to 206850 kPa), typically at least about 2000 psig (13790 kPa), preferably about 4000-10,000 psig (about 27580-68950 kPa), and most preferably about 5000-7000 psig (about 34475-48265 kPa). The homogenization may be carried out in one or more stages, each stage passing one or more times. For example, two and three passes may be used for the homogenization step. In other embodiments, the emulsion may be passed through the homogenizer up to 4 times each, but more preferably 2 to 3 times. This process can produce a stable emulsion having a particle size of less than about 2.1 microns (90%), preferably less than about 1 micron (90%). It is desirable to minimize the heat of contact during homogenization and to maintain all emulsion containers under a nitrogen blanket.

Pre-emulsification of the encapsulate oil or encapsulates in oil in water or aqueous liquid plasticizers can be accomplished using a multi-stage high pressure homogenizer alone or in combination with a colloid mill to achieve minimum particle size. High pressure homogenization produces small particle sizes and can greatly improve the distribution, dispersion and bioavailability of active, sensitive encapsulates within a matrix material. Encapsulation of the emulsion in the matrix material can then be carried out under controlled low temperature and pressure conditions to prevent coalescence, oil separation and extruder fluctuation while yielding a soft, formable mixture or dough containing small droplets of the active, sensitive encapsulates dispersed throughout the dough or mixture. The dough or encapsulate may be cut or shaped and dried to provide substantially non-swelling, discrete storage-stable granules or pellets having an improved release profile of the active encapsulate material. Encapsulates may also optionally be included in the aqueous phase of the emulsion. Emulsifiers may optionally be added to facilitate the preparation and stabilization of the emulsion.

In high pressure homogenization, the oily encapsulates or encapsulates in oil are mixed with water or an aqueous fluid to give oil droplets. In the homogenized stabilized emulsion and in the isolated particles, pellets or encapsulated product of the invention, all or at least substantially all (e.g., at least about 90%) of the oil droplets have a diameter of less than about 50 microns, preferably a diameter of less than about 10 microns, more preferably less than about 2 microns, and most preferably a diameter of less than about 1 micron. In embodiments of the present invention, the oil droplets may be less than about 0.5 microns in diameter. The smaller the droplets, the more stable the emulsion, which allows the dough to be formed without significant coalescence of the droplets and separation of the oil phase. In addition, the reduction of coalescence and fine dispersion can improve the bioavailability of the encapsulate. The reduction of coalescence enhances the coverage or encapsulation of the encapsulate by the continuous phase of the plasticized matrix material (e.g., plasticized semolina or a mixture of semolina and native starch). The use of film-forming components, such as vegetable or animal proteins or protein concentrates, which can also function like emulsifiers, can stabilize the emulsion by forming a thin film surrounding the oil droplets during the emulsification process. Non-film forming emulsifiers, mono-, di-or triglycerides or mixtures thereof, or other molecules characterized by having lipophilic and hydrophilic portions, may be used to enhance the stabilization of the oily enclosure inside the aqueous outer phase. Smaller, substantially non-coalesced droplets do not protrude from the matrix material, thereby reducing the surface of the oily enclosure from air contact.

The oil-in-water emulsion according to the invention may optionally contain an effective emulsifying amount of an emulsifier to help stabilize the emulsion. Conventional emulsifiers used in food and pharmaceutical products, such as monoglycerides and diglycerides, may be selected for use in accordance with the present invention.

After homogenization, the water content of the emulsion is reduced so that the film-forming component forms a film surrounding the oil droplets and encapsulates the encapsulates. The water content of the emulsion may be reduced by mixing the emulsion with a plasticised matrix material, thereby encapsulating the coated oil droplets in the matrix material. The aqueous component, e.g., water, is absorbed by or interacts with the matrix material, thereby increasing the concentration of the film-forming component, causing it to form a film and precipitate around the oil droplets. Thus, if microcapsules of an oil component and a film-forming component are obtained, the microcapsules are further encapsulated by a matrix component. Preferably the matrix material comprises a plasticizable matrix material, such as flour derived from wheat or durum wheat, rye, corn, buckwheat, barley, oats or other grain, which may be plasticized by the aqueous component, thereby encapsulating the oil droplets of the coating within the plasticised matrix material. The mixing of the emulsion and the matrix material may be carried out in a continuous dough mixer or in an extruder to form a dough.

In a preferred embodiment, all or substantially all of the plasticizer may be the aqueous liquid contained in the water or oil-in-water emulsion encapsulate component and the optional added mobilizing plasticizer to solubilize the acidic antioxidant. In addition, a plasticizer for the matrix material, such as water, juice, or other aqueous plasticizers, may be added separately to the matrix material to aid in dough formation or to adjust its viscosity for molding. The formable mixtures or doughs of the present invention can have a total plasticizer content of from about 6 to about 80% by weight, preferably from about 20 to about 45% by weight, based on the weight of the product or dough of the present invention. When high levels of plasticizer are used, for example above about 80% by weight, a low viscosity thin dough is formed that cannot be cut directly on the extrusion die. However, the extruded dough strands may be cut into separate pellets by known mechanical means. Lower plasticizer contents, e.g., less than about 5%, can result in a dry product that is too brittle and can disintegrate after formation. Low plasticizer levels, e.g., less than about 5%, also produce mixtures or doughs that are difficult to extrude unless fat is present. Low plasticizer content also generates frictional heat during extrusion, which can damage heat-sensitive encapsulants.

In embodiments of the invention, the total amount of water and moisture from all sources in the dough, including the water in the emulsion, the water in the antioxidant solution, and the separately added water, may be up to about 80% by weight, such as up to about 35% by weight, based on the weight of the dough. In exemplary embodiments of the present invention, the total amount of moisture in the dough may range from about 2 to 60% by weight. For example, in exemplary embodiments of the present invention, a low moisture content dough, such as a cookie dough or cracker dough, may have a moisture content of about 2-20% by weight of the dough. In other exemplary embodiments of the present invention, high moisture content doughs, such as bread dough, pizza dough, snack dough, cake dough or batter, biscuit dough, and doughs used to make rolls, buns, muffins, breadsticks, and pretzels, may have a moisture content of about 25-60% by weight of the dough.

In the method of incorporating the oil-in-water encapsulate emulsion component into the plasticizable matrix material of the present invention, droplet size is inversely proportional to stability. Thus, a desirable droplet size in the formable mixture or dough of the invention can be from about 0.5 to 50 microns in diameter, preferably less than about 10 microns in diameter, more preferably less than about 2 microns, and most preferably less than about 1 micron in diameter. As a demonstration of emulsion stability, the droplet diameter of the emulsion of the present invention remains substantially constant throughout the period of mixing of the emulsion with the matrix material to form the dough or formable mixture.

The mixing step of the present invention may preferably be carried out in an extruder to form a mixture of: 1) an oil-in-water encapsulate emulsion component, 2) a dry matrix material component comprising a plasticizable matrix material, optionally a non-plasticizable matrix material, optionally a release rate controlling agent and optionally a flavorant, 3) a solubilized acidic antioxidant solution or component which may comprise an acidic antioxidant, optionally a mobilizing plasticizer or softener, such as glycerol, and water, and 4) additional added water. Low extrusion pressures and temperatures are used to avoid coalescence, oil separation and extrusion fluctuations. Generally, low viscosity is required for extrusion at low pressures. However, increasing the viscosity increases shear strength, thereby breaking the emulsion.

The low extrusion pressure helps prevent coalescence, creaming and extrusion fluctuations. To achieve low pressure, the viscosity of the dough can be reduced by increasing the amount of plasticizer (e.g., water). However, the viscosity of the dough should be high enough to obtain a formable and cuttable mixture at the die. Desirable extrusion pressures at which the formable mixture can be formed are from about 14.5 to 2175 psig (about 100 kPa to about 14997 kPa), preferably from about 29 to 1450 psig (about 200 kPa 9998 kPa), more preferably from about 72.5 to 725 psig (about 500 kPa 4999 kPa). In embodiments of the invention, the die operating pressure may be in the range of about 70-800 psig (about 483-5516 kPa), typically about 100-300 psig (about 690-2069 kPa).

In preparing the shapeable mixture or dough of the present invention, it is desirable to achieve a balance of shear force to reduce particle size on the one hand and lower viscosity to reduce shear force on the other hand in the mixing process of the present invention. Reducing the particle size reduces coalescence and ensures that each encapsulate droplet is protected within the particles of the invention.

In an embodiment of the invention, a premix or separate feed of the matrix material containing the protein component and the starch component may be fed to a first barrel of the extruder, to which a plasticizer/acidic antioxidant may be added, followed by the addition of the pre-emulsified components and optionally glycerol in a second barrel, and then the optional addition of water may be injected into a third barrel at the upstream end of the extruder to achieve plasticization of the plasticizable matrix material without significant coalescence or oil separation, or fluctuations in extrusion yield, even at high oil contents. Mixing continues towards the extrusion die while optionally adjusting the product temperature to obtain sufficient formability. The plasticized matrix material is plasticized by water or an aqueous liquid and optionally a mobilizing plasticizer in a plasticizer/acidic antioxidant solution. The optional substantially non-plasticizable matrix component is typically not plasticized by the liquid plasticizer below about 60 ℃, preferably below about 50 ℃, and most preferably below about 45 ℃, e.g., at room temperature or as low as about 0 ℃. It is not necessary to remove the liquid plasticizer prior to extrusion to adjust the viscosity of the mixture for formability. In embodiments of the invention, the barrel temperature of the extruder may be maintained at about-5 ℃ to about 25 ℃, preferably about 5-10 ℃. Typically, the die operating temperature may be from about 10 to 50 deg.C, such as from about 15 to 30 deg.C.

A formable mixture can be obtained without substantially gelling or cooking the plasticized matrix material or optional substantially non-plasticized matrix components. The plasticized matrix material in the shapeable mixture can become glassy upon drying, even without being cooked or substantially gelatinized during the plasticizing process to yield the shapeable mixture. However, the use of non-aqueous activating plasticizers or softeners, such as glycerin, desirably results in a non-brittle texture that is not prone to cracking, leaking oil, and penetrating ambient oxygen. In addition, the starch component reduces the rubbery state and viscosity, facilitating extrusion through a die.

In embodiments of the present invention, the amount of active ingredient or encapsulate that may be encapsulated or embedded in the matrix may be from about 5 to about 30% by weight, based on the total weight of the plasticizable matrix material of the formable mixture or dough of the present invention, or from about 5 to about 20% by weight, preferably from about 8 to about 15% by weight, based on the weight of the encapsulated product.

The mixture or dough may be extruded through an extrusion die and cut, or formed into tablets or pellets, with the extrudate being non-expanding or substantially non-expanding.

In an embodiment of the invention, the dough may be extruded through a circular orifice having a diameter of 0.2 to 3 mm (preferably about 0.4 to 0.9 mm), with a flat cut of 0.2 to 3 mm (preferably about 0.4 to 0.9 mm). For example, pellets having a size of 0.5 mm (diameter) × 0.5 mm (length) can be produced. The dough may be kept cool, for example below about 30 c, during extrusion.

A flow agent, such as starch or calcium carbonate, may be added at the cutting device to maintain the separating properties of the granules or pellets and to aid air transport of the pellets, as they may stick to each other at high extrusion water content or high matrix protein content.

The matrix may be composed of one or several different ingredients, including durum wheat flour, sodium or potassium caseinate, whey protein isolate, wheat protein (or protein derived from other animals or plants), heat treated flour (e.g. heat treated wheat flour), starch, alginate and other hydrocolloids to provide additional oxygen protection.

In an embodiment of the invention, the freshly extruded pellets may contain from about 5 to about 30 weight percent oil and from about 15 to about 35 weight percent moisture, based on the total weight of the freshly extruded pellets.

The extrudate or tablet may then be surface dried using conventional drying equipment, such as a rotary dryer. The pellets may be conveyed to a long (about 2 feet inside diameter by 4 feet long) rotary coater using an air purge counter to the extrudate or pellet flow. Preferably, more effective drying is performed with dehumidified air. The surface drying of the pellets may be carried out using hot air (dehumidified or ambient air) up to about 280 ℃. Typically, the air drying temperature may be from about 37 ℃ to about 82 ℃, but more preferably the air temperature is from about 50 ℃ to about 60 ℃. Surface drying facilitates optional subsequent coating. Even at high hot air temperatures, the product temperature at the coater outlet can remain below about 100 ° f (about 37.7 ℃). In embodiments of the invention, up to about 10% by weight of the moisture or more, for example up to about 20% by weight of the pellets may be removed during surface drying in a rotary dryer. Other conventional drying equipment, such as fluidized bed drying or fixed bed drying, may also be used.

In embodiments of the invention, the surface-dried extrudate or pellet or tablet may optionally be coated or surface treated with a protective film or coating to prevent premature or enable controlled release of the encapsulate from the pellet or tablet. Surface drying after extrusion and before coating facilitates the application of the protective coating solution. For example, a drier pellet may receive a higher amount of coating before agglomeration or agglomeration occurs. The protective coating may be hydrophilic or oleophobic, thereby inhibiting the oil component from migrating toward the pellet surface and oxidizing. Examples of film-forming substances or protective coatings which may be used are proteins derived from whey, corn, wheat, soy or other vegetable or animal sources, such as aquazein (an aqueous solution of corn protein) and denatured whey protein isolate solutions (with or without plasticizers such as sucrose or glycerol); fats, such as melted chocolate fat; shellac, waxes, film forming starch solutions, alginates, other non-starch polysaccharides, enteric coatings and mixtures thereof.

A denatured whey protein isolate film plasticized with sucrose is preferred because of its oxygen barrier function. Other biopolymers which may be used instead of or in addition to denatured whey protein are soy protein isolate, modified food starch, hydroxymethyl propyl methyl cellulose and shellac. An exemplary polymer/plasticizer ratio that can be employed is from about 1:0.25 to about 1:3 polymer/plasticizer (by weight). For example, a coating or film composition for coating on surface-dried pellets may be prepared as follows: the solution consisting of deionized water and whey protein was heated to about 90 c and held at that temperature for about 30 minutes to denature the protein. The solution may then be cooled and a plasticizer (e.g., sucrose) added in a ratio of 1 part by weight protein to 3 parts plasticizer. The coating solution may be formulated with 5 wt.% denatured whey protein, 15 wt.% sucrose, and 85 wt.% deionized water.

The film-forming materials and protective coatings may also contain a flavoring material and auxiliary components to retard or prevent the access of light, oxygen and/or water to the substrate. Light blocking substances such as titanium dioxide, carbon black, edible inks, cocoa, etc. may be used.

In an embodiment of the invention, the coating solution may be applied in the form of a fine mist atomized with nitrogen, sprayed on the surface of the pellets in a rotary coater. Multiple coats can be applied with drying in between. The coating material may comprise about 1-20% of the final product mass.

Application of the optional protective coating may also be accomplished by pan coating of the tablets and pellets directly after extrusion and before final drying. Multiple pan coatings may be applied with drying between the two coatings. Fluid bed coating, drum coating with a rotary coater, is also an option for coating the tablets or pellets, but pan coating is more efficient and cost effective.

The uncoated pellets or the coated pellets can be dried to their final moisture content in conventional drying equipment such as fixed bed tray dryers, continuous conventional dryers or fluidized bed (continuous or batch) dryers. Convection drying may be carried out using dehumidified or ambient air, nitrogen or carbon dioxide. An exemplary final moisture content may be about 2-10% by weight of the dry pellets or granules. The drying temperature may be from ambient to 100 deg.C, or more preferably from ambient to about 65 deg.C. The pellets or granules may be dried to a storage stable water activity of less than or equal to about 0.7 and a storage stability or shelf life of at least about 6 months, preferably at least about 12 months, most preferably at least about 36 months. In embodiments of the invention, the storage stable water activity in the moist product may be less than or equal to about 0.9, at which time an optional anti-mold or antimicrobial agent may be used.

In an embodiment of the invention, the encapsulated component, such as fish or linseed oil, or algae-derived oil, may contain up to about 90% by weight of an easily oxidizable component, such as up to about 45% by weight, preferably about 1-40% by weight, more preferably about 10-30% by weight of an oil or other easily oxidizable component, such as a polyunsaturated fatty acid.

The products of the invention may have a hard, non-brittle or semi-glassy texture. The product of the invention may be in the form of discrete granules, pellets or tablets. They may be spherical, curvilinear or lenticular, planar circular, ovoid, etc. Preferably spherical. In embodiments of the invention, the particles may have a diameter of about 0.2 to 3 mm, preferably about 0.4 to 0.9 mm, a length of about 0.2 to 3 mm, preferably about 0.4 to 0.9 mm, and a length/diameter ratio (l/d) of about 0.5 to about 2, preferably about 1. The particles are generally uniform in size, may be hard or partially glassy, are substantially dense granules that are visually and texturally compatible with the baked good, and are preferably not discernible or not readily discernible to the consumer with the naked eye or from the texture. The products of the invention are non-swelling, do not normally ferment, and may exhibit a non-porous, substantially non-cellular structure. The starch component in the matrix may be substantially ungelatinized or partially gelatinized and not significantly denatured or dextrinized. An exemplary specific gravity of the product of the present invention is about 800-1500 g/liter (about 0.8-1.5 g/cm)³）。

The encapsulated products of the present invention can be incorporated into baked good doughs and baked goods using conventional baked good formulations, mixing steps and equipment.

In addition, the process of the present invention comprises encapsulating an oil containing polyunsaturated fatty acids for incorporation into baked goods without significant smearing and dissolution of the encapsulated product during mixing of the encapsulated product in the baked good dough or batter. The encapsulation process involves forming an oil-in-water emulsion containing at least one polyunsaturated fatty acid and a film-forming component, preferably a film-forming protein. The oil-in-water emulsion is mixed with a matrix material, a liquid plasticizer for plasticizing the matrix material, and an acidic antioxidant for preventing oxidation of the at least one polyunsaturated fatty acid. The matrix material comprises a starch component and a protein component, wherein the amount of protein in the matrix material is from about 35 to about 75 weight percent, preferably from about 45 to about 65 weight percent, based on the weight of the matrix material. Said mixing is carried out to obtain a formable mixture, wherein the matrix material contains an acidic antioxidant and encapsulates the oil droplets of the oil-in-water emulsion. Forming the formable mixture into a tablet and drying the tablet to obtain a dry tablet of the encapsulated product, wherein the protein content of the encapsulated product is from about 25% to about 65% by weight, preferably from about 40% to about 60% by weight, based on the weight of the encapsulated product. In an embodiment of the invention, the starch component and the protein component may be pre-mixed to obtain the matrix material, and the matrix material may be mixed with the acidic antioxidant, the emulsion and the plasticizer in order to at least substantially plasticize the matrix material and to substantially uniformly distribute the antioxidant throughout the matrix material.

A method of incorporating an oil containing polyunsaturated fatty acids into a baked good comprises mixing the encapsulated product with baked good dough or batter ingredients comprising flour and water to obtain a dough or batter wherein the encapsulated product does not significantly smear and dissolve. The dough or batter may be baked to obtain baked goods such as bread, cookies, rolls, buns, biscuits, cakes, muffins, breadsticks, pretzels, pizzas, cookies, crackers, and snacks without significant smearing and dissolution of the encapsulated product in the baked goods.

The invention is further illustrated by the following non-limiting examples in which all parts, percentages, ratios and ratios are by weight and all temperatures are in degrees Celsius unless otherwise indicated.

Example 1

This example shows the preparation of an encapsulated product containing polyunsaturated fatty acids (algal oil) and the effect of the matrix material protein content, the protein content of the encapsulated product and the pellet size on the physical survival of the encapsulated product in bread. This example also demonstrates the stabilizing effect of an acidic antioxidant (ascorbic acid) on omega-3 oil incorporated into an encapsulated product in bread. The ingredients and their relative amounts that may be used to prepare the encapsulated product are shown in table 1:

table 1: product formulas for bread-1 through bread-19 in% by weight after extrusion/anti-caking processing:

the product formulations of the various breads, expressed in% by weight after extrusion (wet) and% by weight of the final product (dry) containing a final moisture content of 6.5%, are shown in table 2:

table 2: bread-1 to bread-19 product formulations expressed in weight% of the final product (dry) after extrusion (wet) and containing 6.5% final moisture:

emulsions may be prepared according to the invention as follows: algae oil, Grindox 204 antioxidant TBHQ, a portion of water, and sodium caseinate dissolved in 10% by weight water were mixed in a line mixer to form a pre-emulsion or macroemulsion. The pre-emulsion was then subjected to high pressure homogenization in a Microfluidics homogenizer at about 10000 psi to provide a stable emulsion. Durum flour and wheat protein isolate may be pre-mixed in a ribbon blender to obtain a substantially homogeneous matrix material, which may then be fed into the first barrel of the extruder. An acidic antioxidant may be added to the first barrel for substantially uniform mixing with the matrix material. The stabilized emulsion is fed into the second barrel, followed by the addition of the remaining water and optionally glycerol in the third barrel. The ingredients were mixed, blended and kneaded in the remaining extruder barrel, extruded through a plurality of die orifices at a die temperature of about 122 ° f (50 ℃) and a die pressure of about 500 psi, and cut into pellets. An anti-caking mixture of corn starch and calcium carbonate may be applied to the surface of the pellets in the pellet cutting box, and the pellets may then be dried to provide an encapsulated product having a moisture content of about 6.5% by weight. A blue food dye may be included in several samples to ascertain smearing and dissolution of the pellets during preparation of the bread dough.

The pellets were incorporated into a conventional bread dough using a conventional bread maker set to moderate crust formation. The bread recipe is given in table 3, and the bread preparation procedure is as follows:

table 3: white bread formula adjusted for bread machine

The method comprises the following steps: (for supplementary advice see bread machine description)

1. The vane shaft is oiled and the vanes are mounted on the shaft.

2. Weighing water and putting into a bread tray.

3. Adding bread mixture.

4. Yeast and DHA encapsulates were added and gently stirred into the top of the mix.

The toaster was started at the 1.5 pound white bread, medium crust color setting.

Calculating the addition amount of DHA:

the dosage of each part is as follows: 32 mg/50 g

The total weight of each bread: 691.4 g

The intake parts of each bread are as follows: 13.8

Number of pellets per bread: 10.8 g.

The results and methods are shown in table 4 and fig. 1. As shown in table 4 and fig. 1, as pellet particle size decreases, higher protein levels are required to avoid undesirable smearing and dissolution of the pellets during dough mixing and baking. For particle sizes of about 2.5 mm in diameter, the protein content of the pellets needs to be at least about 25% by weight to avoid dissolution or smearing of the pellets in the dough and baked goods, while a protein content above 40% by weight will leave particles having a diameter of only 0.5 mm undissolved or smeared.

In addition, sensory evaluations performed by a panel showed that samples of bread and samples of matrix material without acidic antioxidants in which the encapsulated product failed the physical viability test exhibited fishy spoilage, unpleasant odors and off-tastes. The best results were obtained with bread 19:

example 2

This example demonstrates the preparation of an encapsulated product containing polyunsaturated fatty acids (algal oil) and the use of the encapsulated product in commercial white bread. This example demonstrates the effect of the protein content of the matrix material, the protein content of the encapsulated product and the glycerol content of the encapsulated product on the sensory and oxidative stability of the encapsulated product, the physical survival of the encapsulated product in commercial style bread and the sensory stability of bread fortified with the encapsulated product.

Preparation of encapsulated products

The ingredients and their relative amounts that can be used to prepare the encapsulated product are listed in table 5:

emulsions may be prepared according to the invention as follows: algae oil, Grindox 204 antioxidant TBHQ, a portion of water, and sodium caseinate dissolved in 10% by weight of water were mixed in a pipeline mixer to form a pre-emulsion or macroemulsion. The pre-emulsion was then subjected to high pressure homogenization in a Microfluidics homogenizer at about 10,000 psi to provide a stable emulsion. Durum flour and wheat protein isolate may be pre-blended in a ribbon blender to obtain a substantially homogeneous matrix material, which may then be fed into the first barrel of the extruder. Acidic antioxidants (ascorbic acid and citric acid) may be added to the first barrel for substantially uniform mixing with the matrix material. Water and optionally glycerol may be fed into the extruder at the end of the first barrel. The stabilized emulsion may be fed into the second barrel. The ingredients may be mixed, blended and kneaded in the remaining extruder barrel and extruded and cut into pellets through a plurality of die holes having a diameter of 0.5 mm at a die temperature of about 84 ° f (29 ℃) to about 105 ° f (41 ℃) and a die pressure of about 175 psi to about 545 psi. An anti-caking mixture of corn starch and calcium carbonate may be applied to the pellets in the pellet cutting box and the pellets dried to provide an encapsulated product having a moisture content of about 6.5% by weight. The samples contained a blue color of food dye to ascertain smearing and dissolution of the pellets during preparation of the bread dough.

Preparation of bread containing encapsulated product

The pellets are incorporated into conventional bread dough using conventional commercial molding bread equipment. The bread recipe is shown in table 6, and the commercial bread was prepared as follows:

table 6: white bread formula adjusted for commercial bread baking method

For long pan bread, the target weight was 23.5 ounces or 666 grams, and the above recipe was calculated for 7.4 loaves.

For the addition of DHA, the calibration weight was 675 g, see DHA calculation below.

The claimed weight of the baked bread was 20 ounces or 567 grams.

The baking loss is 10-15%.

The dough moisture was 43.2%.

The moisture of the baked bread was 33.3%.

Calculation of DHA addition:

the dosage of each part is as follows: 32 mg/50 g

Total weight of each baked: 567.0 g

The intake parts of each bread are as follows: 11.3

Weight of each bread pellet: 8.9 g

Amount of pellets applied to the above batch: 65.5 g

The baking method of the commercial bread comprises the following steps:

1. starting from the above formulation, all ingredients to be put into a commercial mixer were weighed out.

2. All ingredients were placed in a 12 quart, 3 speed Habart mixer (model # HL 200).

3. Mix at low speed for 3 minutes and then at high speed for 10 minutes.

4. The dough was removed from the mixer. Covered with plastic cloth and left to stand for 5 minutes.

5. The dough temperature was checked and should be around 78-90 ℉.

6. Cut, weighed and rolled into dough balls, and then left for 10 minutes.

7. The dough balls were made into disk-like lengths by passing them through a commercial noodle press (ACME).

8. The dough in sheet form is placed into a greased pan.

9. The disks were placed in a preheated commercial hair box (ANNETS, set at 105F.) for about 1.5 hours. When the height of the dough is level with the edge of the pan, the dough is ready for baking.

10. The pan and leavened bread dough was placed in a commercial oven preheated to 375 ° f for 28 minutes.

11. Cooling after removing from the oven until the internal temperature is below 100 ℉ and slicing.

12. Cut into slices with a commercial bread cutter (2 slices weighing about 50 g) and put into plastic bags for bread.

Test results for encapsulated products and bread containing encapsulated products

The protein and glycerol levels and extrudate moisture levels that can be used to prepare the encapsulated products are listed in table 7. Table 7 also lists Oxipres stability of the encapsulated product, organoleptic stability of the pellets and commercial white bread samples, and physical survival rate of the pellets in the white bread samples:

table 7: process variables and results regarding physical, organoleptic and chemical stability for the preparation of DHA encapsulated products

Constant value:

a homogenizer: microfluidics micro-jet homogenizer

Homogenizing: pass 1 time at 10,000 psi

Antioxidant: TBHO, 200 ppm

Acid concentration in the final product: 3.5% d.m. ascorbic acid, 3% d.m. citric acid (d.m. denotes dry weight)

An encapsulate: martek DHA-S algal oil

Oil content: 12.5% d.m (4.4% d.m. DHA)

Diameter of the die hole: 0.5 mm

Extruder throughput: 300 g/min (18 kg/hr)

Tables 8 and 9 show the statistical results obtained from the full factorial design set forth in table 7. The results in tables 8 and 9 were calculated using the Design of the experimental software (Design Expert, Stat-Ease, Inc.). For the analysis of variance calculation, a user-defined surface response design is employed, where the design points used may be selected. For statistical analysis of the response parameters, a quadratic model is selected.

Table 8: analysis of variance (ANOVA) results with respect to response surface quadratic model

A value of "Prob > F" less than 0.0500 indicates that the model term is meaningful. Values greater than 0.1000 indicate that the model term is meaningless. Model reduction may improve the model if there are many meaningless model terms (not included as needed to support a hierarchical hierarchy system);

the "R-square" is a determinant coefficient that measures the dispersion within the data set considered by the statistical model. It provides a measure of how good the future results predicted by the model are likely to be. An R-Squared of 1.0 (100%) indicates a perfect agreement between the result and the value used for prediction;

the "Adeq Precision" measures the signal to noise ratio. Ratios greater than 4 are desirable and indicate that the model used can be used to navigate the design space.

Table 9: final equation based on coding factor

Note: the numbers shown in bold are the significance coefficients of the regression equation.

A synergistic relationship has been shown with respect to the effect of the protein in the bread pellets on chemical, organoleptic and physical stability. The increase in protein in the pellets significantly reduced the mixed fishy/painty smell in the pellets, and reduced the mixed fishy/painty taste in the bread, with the results indicating an increase in Oxipres stability and pellet survival. The increase in glycerin significantly improves Oxipres stability of the pellets prior to incorporation into bread and reduces their mixed fishy/painty smell, but reduces the survival rate of the pellets in bread. However, the results show that the high glycerol content does not negatively affect the organoleptic properties of the bread during a shelf life of 6 months at freezing temperature for the pellets and during a shelf life of 14 days at room temperature for bread with a DHA concentration of 32 mg per serving.

Figure 2 shows a superimposed graph of the organoleptic and physical stability of bread pellets as a function of the glycerol and wheat protein content. To form the graph, the lowest limit for physical stability and the highest limit for sensory stability are set, and then a superimposed graph is formed by highlighting the preferred operability region. For "shot fishy + painty", the limit was chosen to be ≦ 3, since a mixed fishy/painty score means that each individual score does not exceed 3, which is the threshold for detection. For "physical stability", the limit value is chosen to be ≧ 0.5. An average pellet count of 0.5 indicates that at least one viable pellet and at least one physically intact pellet can be found on each secondary cross-section of the bread or on each slice of bread. As shown in fig. 2, the Oxipres stability of the pellets prepared under the preferred conditions will be between about 9.6 to about 11.6, while the organoleptic stability of the bread prepared with the pellets will be between 0 and 0.5 with respect to the "mixed fishy and painty" score. Figure 2 shows the preferred operating window for glycerol and protein, where the pellets are free of fishy and painty odors after 6 months storage at freezing temperatures (nitrogen sparge, sealed) and physically survive in commercial white bread application without significant smearing or dissolution. As shown in fig. 2, the following ranges of use for glycerol and protein determine the preferred working window for the design space studied:

glycerol: 1.0% -7.5% by weight of the encapsulated product or final product; and

protein: from 30.0% to 77.5% by weight based on the weight of the substrate.

Claims (87)

1. An encapsulated product for baked goods which can be incorporated into baked goods dough or batter without significant smearing or dissolution in the dough or batter, said encapsulated product comprising:

a) oil droplets comprising at least one polyunsaturated fatty acid,

b) a film-forming component comprising protein, the film-forming component coating the oil droplets,

c) a matrix material encapsulating the coated oil droplets, the matrix material comprising a starch component and a protein component,

d) a liquid plasticizer for plasticizing the matrix material, and

e) an acidic antioxidant dispersed throughout the plasticized matrix material,

wherein the protein content of the encapsulated product is from 25 to 65% by weight based on the weight of the encapsulated product and the mass of protein in the matrix material is from 35 to 75% by weight based on the weight of the matrix material.

2. An encapsulated product as claimed in claim 1 wherein the protein content of the encapsulated product is from 40 to 60% by weight based on the weight of the encapsulated product.

3. An encapsulated product as claimed in claim 1 wherein the protein content of the matrix material is from 45 to 65% by weight based on the weight of the matrix material.

4. An encapsulated product as claimed in claim 2 wherein the protein content of the matrix material is from 45 to 65% by weight based on the weight of the matrix material.

5. The encapsulated product of claim 1 wherein the starch component comprises at least one selected from the group consisting of pregelatinized or modified starch, corn flour, wheat flour, rice flour, barley flour, oat flour, and rye flour.

6. An encapsulated product as claimed in claim 1 wherein said protein component comprises at least one member selected from the group consisting of vegetable proteins, and animal proteins.

7. An encapsulated product as claimed in claim 1 wherein said protein component comprises at least one member selected from the group consisting of wheat protein isolate, gelatin, casein, caseinate, soy protein isolate and whey protein isolate.

8. An encapsulated product as claimed in claim 5 wherein said protein component comprises at least one member selected from the group consisting of wheat protein isolate, gelatin, casein, caseinate, soy protein isolate and whey protein isolate.

9. An encapsulated product as claimed in claim 1 wherein said matrix material comprises durum wheat flour and wheat protein isolate.

10. An encapsulated product as claimed in claim 1 wherein the encapsulated product is in the form of discrete particles or pellets having a diameter of 0.2 to 3.0 mm.

11. An encapsulated product as claimed in claim 1 wherein said plasticizer comprises at least one liquid polyol providing mobility of said acidic antioxidant in the plasticized matrix material in an amount of less than 5% by weight based on the weight of the encapsulated product.

12. An encapsulated product as claimed in claim 11 wherein said at least one polyol comprises at least one member selected from the group consisting of glycerol, propylene glycol and sorbitol and said film forming component comprises at least one caseinate.

13. An encapsulated product as claimed in claim 1 wherein said oil droplets comprise at least one member selected from the group consisting of fish oil, algal oil, linseed oil and oils derived from plants genetically modified to contain polyunsaturated fatty acids.

14. An encapsulated product as claimed in claim 1 wherein said acidic antioxidant comprises at least one member selected from the group consisting of citric acid, ascorbic acid, erythorbic acid and salts thereof.

15. An encapsulated product as claimed in claim 14 wherein the amount of said acidic antioxidant is from 0.5 to 10% by weight based on the weight of the encapsulated product.

16. An encapsulated product as claimed in claim 15 wherein the amount of oil is from 5 to 20% by weight of the encapsulated product.

17. An encapsulated product as claimed in claim 1 which has a storage or shelf stability of at least 6 months under nitrogen sparged ambient conditions.

18. An encapsulated product as claimed in claim 1 which has a storage or shelf stability of at least 12 months under nitrogen sparged ambient conditions.

19. A baked good dough or batter comprising an encapsulated product according to claim 1.

20. Bread dough comprising the encapsulated product of claim 1.

21. A baked good comprising the encapsulated product of claim 1.

22. The baked good of claim 19 selected from the group consisting of bread, cookies, cakes, muffins, pretzels, pizzas, and snacks.

23. A baked good comprising the encapsulated product of claim 17 having an omega-3 fatty acid concentration of at least 10 mg per serving, wherein the baked good has a shelf stability of at least 14 days after baking.

24. A baked good comprising the encapsulated product of claim 17 having an omega-3 fatty acid concentration of at least 10 mg per serving, wherein the baked good has a shelf stability of at least 6 months after baking.

25. A baked food mix comprising the encapsulated product of claim 1.

26. A package in the form of a bag or pouch comprising a high moisture and/or high oxygen barrier material containing a nitrogen purged encapsulated product according to claim 1.

27. A baked food product kit comprising the package of claim 26 and a package containing a premix of a baked food ingredient comprising flour.

28. A method of encapsulating polyunsaturated fatty acid-containing oils for incorporation into baked goods without significant smearing and dissolution of the encapsulated product during mixing in the baked good dough or batter, said method comprising:

a) forming an oil-in-water emulsion comprising at least one polyunsaturated fatty acid and a protein-containing film-forming component,

b) mixing said oil-in-water emulsion with a matrix material, said matrix material comprising a starch component and a protein component, the protein being present in the matrix material in an amount of from 35 to 75% by weight based on the weight of the matrix material, a liquid plasticizer for plasticizing the matrix material and an acidic antioxidant for preventing oxidation of said at least one polyunsaturated fatty acid, said mixing being such as to obtain a formable mixture in which the matrix material comprises the acidic antioxidant and encapsulates oil droplets in said oil-in-water emulsion,

c) forming said formable mixture into a sheet, and

d) drying said tablet to obtain a dry tablet of encapsulated product, wherein the protein content of the encapsulated product is from 25 to 65% by weight based on the weight of the encapsulated product.

29. The method of claim 28, wherein said starch component and protein component are preblended to provide said matrix material, which is mixed with said acidic antioxidant, said emulsion, and said plasticizer to plasticize said matrix material and to uniformly distribute said acidic antioxidant throughout said matrix material.

30. The method of claim 29 wherein in said tablet said oil-in-water emulsion comprises oil droplets containing at least one polyunsaturated fatty acid and each having a diameter of less than 2 microns, said film-forming component surrounding the oil droplets, and a matrix material and an acidic antioxidant surrounding the coated oil droplets.

31. The method of claim 30, wherein the oil-in-water emulsion is homogenized in a homogenizer to obtain said oil droplets, wherein said emulsion, antioxidant, matrix material and plasticizer are mixed in an extruder.

32. The process of claim 28, wherein the protein content of the encapsulated product is from 40 to 60% by weight based on the weight of the encapsulated product.

33. The method of claim 28, wherein the protein content in the matrix material is 45-65% by weight based on the weight of the matrix material.

34. The method of claim 32, wherein the protein content in the matrix material is 45-65% by weight based on the weight of the matrix material.

35. The method of claim 28 wherein the starch component comprises at least one selected from the group consisting of pregelatinized or modified starch, corn starch, wheat flour, rice flour, barley flour, oat flour, and rye flour, and wherein the protein component comprises at least one selected from the group consisting of vegetable proteins, and animal proteins.

36. The method of claim 35, wherein said protein component comprises at least one member selected from the group consisting of wheat protein isolate, gelatin, casein, caseinate, soy protein isolate and whey protein isolate.

37. The process of claim 28, wherein said matrix material comprises durum wheat flour and wheat protein isolate and said encapsulated product is in the form of discrete particles or pellets having a diameter of 0.2 to 3.0 mm.

38. The method of claim 28 wherein said oil droplets comprise at least one member selected from the group consisting of fish oil, algae oil, linseed oil and vegetable oils derived from genetically modified oils containing polyunsaturated fatty acids, said acidic antioxidants comprise at least one member selected from the group consisting of citric acid, ascorbic acid, erythorbic acid and salts thereof, the amount of acidic antioxidants is from 0.5 to 10% by weight based on the weight of the encapsulated product, and the amount of oil is from 5 to 20% by weight based on the weight of the encapsulated product.

39. A method of incorporating an oil containing polyunsaturated fatty acids into a baked good comprising mixing the encapsulated product of claim 1 with baked good dough ingredients comprising flour and water to obtain a dough without significant smearing and dissolution of the encapsulated product in the dough and during baking of the dough.

40. The method of claim 39 wherein said baked good is selected from the group consisting of bread, cookies, cakes, muffins, pretzels, pizzas, and snacks.

41. The method of claim 39, wherein the baked good is bread, the bread has a concentration of omega-3 fatty acids of at least 16 mg per 50 g serving, and the bread has a shelf stability of at least 14 days after baking.

42. The method of claim 39 wherein the baked good is muffin, the concentration of omega-3 fatty acids in the muffin is at least 16 mg per serving, and the muffin has a shelf stability of at least 14 days after baking.

43. The method of claim 39 wherein the baked good is a cookie having a concentration of omega-3 fatty acids of at least 16 mg per serving and a storage stability of the cookie for at least 6 months after baking.

44. The process of claim 39, wherein said matrix material comprises durum wheat flour and wheat protein isolate and wherein said encapsulated product is in the form of discrete particles or pellets having a diameter of 0.2 to 3.0 mm.

45. An encapsulated product for baked goods which can be incorporated into baked goods dough or batter without significant smearing or dissolution occurring therein, said encapsulated product comprising:

a) oil droplets comprising at least one polyunsaturated fatty acid,

b) a film-forming component comprising protein, the film-forming component coating the oil droplets,

c) a matrix material encapsulating the coated oil droplets, the matrix material comprising a starch component and a protein component,

d) a liquid plasticizer for plasticizing the matrix material, and

e) an acidic antioxidant dispersed throughout the plasticized matrix material,

wherein the protein content of the encapsulated product is from 15 to 65% by weight based on the weight of the encapsulated product and the protein content of the matrix material is from 25 to 77.5% by weight based on the weight of the matrix material.

46. An encapsulated product as claimed in claim 45 wherein the protein content of the encapsulated product is from 20 to 55% by weight based on the weight of the encapsulated product.

47. An encapsulated product as claimed in claim 45 wherein the protein content in the matrix material is from 30 to 65% by weight based on the weight of the matrix material.

48. An encapsulated product as claimed in claim 46 wherein the protein content in the matrix material is from 30 to 65% by weight based on the weight of the matrix material.

49. An encapsulated product as claimed in claim 45 wherein the plasticiser contains at least one liquid polyol providing mobility within the plasticised matrix material to the acidic antioxidant in an amount of less than or equal to 20% by weight based on the weight of the encapsulated product.

50. An encapsulated product as claimed in claim 49 wherein the amount of said at least one liquid polyol is from 1 to 7.5% by weight based on the weight of the encapsulated product.

51. An encapsulated product as claimed in claim 45 wherein the protein content of the matrix material is from 25 to 35% by weight based on the weight of the matrix material and the protein content of the encapsulated product is from 15 to 25% by weight based on the weight of the encapsulated product or final product.

52. An encapsulated product as claimed in claim 49 wherein said at least one liquid polyol is present in an amount of from 5 to 20% by weight based on the weight of the encapsulated product.

53. A method for encapsulating an unsaturated fatty acid-containing oil for incorporation into baked goods without significant smearing and dissolution of the encapsulated product during mixing of the encapsulated product in the baked good dough or batter, comprising:

a) forming an oil-in-water emulsion comprising at least one polyunsaturated fatty acid and a protein-containing film-forming component,

b) mixing the oil-in-water emulsion with a matrix material comprising a starch component and a protein component, the protein being present in the matrix material in an amount of from 25 to 77.5% by weight based on the weight of the matrix material, a liquid plasticizer for plasticizing the matrix material and an acidic antioxidant for preventing oxidation of the at least one polyunsaturated fatty acid, said mixing being such as to obtain a formable mixture in which the matrix material comprises said acidic antioxidant and encapsulates the oil droplets of said oil-in-water emulsion,

c) forming said formable mixture into a sheet, and

d) drying said tablet to obtain a dry tablet of encapsulated product, wherein the protein content of the encapsulated product is from 15 to 65% by weight based on the weight of the encapsulated product.

54. The process of claim 53 wherein the protein content of the encapsulated product is from 20 to 55% by weight based on the weight of the encapsulated product.

55. The method of claim 53, wherein the protein content in the matrix material is 30-65% by weight of the matrix material.

56. The method of claim 54, wherein the protein content in the matrix material is 30-65% by weight of the matrix material.

57. The method of claim 53 wherein said plasticizer comprises at least one liquid polyol for providing mobility in the plasticized matrix material to said acidic antioxidant in an amount of less than or equal to 20 weight percent based on the weight of the encapsulated product.

58. The process of claim 57 wherein the amount of said at least one liquid polyol is from 1 to 7.5% by weight based on the weight of the encapsulated product.

59. The method of claim 53 wherein the protein content in the matrix material is from 25 to 35% by weight based on the weight of the matrix material and the protein content of the encapsulated product is from 15 to 25% by weight based on the weight of the encapsulated product.

60. The process of claim 57 wherein the amount of said at least one liquid polyol is from 5 to 20% by weight based on the weight of the encapsulated product.

61. An encapsulated product as claimed in claim 1 wherein said starch component comprises high gluten content flour.

62. An encapsulated product as claimed in claim 1 wherein said starch component comprises durum wheat flour.

63. An encapsulated product as claimed in claim 1 wherein said starch component comprises a meal.

64. An encapsulated product as claimed in claim 1 wherein said protein component comprises vital wheat gluten.

65. An encapsulated product as claimed in claim 5 wherein said protein component comprises vital wheat gluten.

66. An encapsulated product as claimed in claim 61 wherein said protein component comprises vital wheat gluten.

67. An encapsulated product as claimed in claim 62 wherein said protein component comprises vital wheat gluten.

68. An encapsulated product as claimed in claim 63 wherein said protein component comprises vital wheat gluten.

69. The baked good of claim 19 selected from the group consisting of a bun, loaf, cookie, and cracker.

70. The method of claim 28, wherein the starch component comprises a high gluten content flour and wherein the protein component comprises at least one member selected from the group consisting of vegetable protein, and animal protein.

71. The method of claim 28, wherein the starch component comprises durum wheat flour and wherein the protein component comprises at least one selected from the group consisting of vegetable protein, and animal protein.

72. The method of claim 28 wherein the starch component comprises meal and wherein the protein component comprises at least one member selected from the group consisting of vegetable protein, and animal protein.

73. The method of claim 35 wherein said protein component comprises vital wheat gluten.

74. The method of claim 39 wherein said baked good is selected from the group consisting of a bun, loaf, cookie, and cracker.

75. The process of claim 39, wherein said encapsulated product is in the form of discrete particles or pellets having a diameter of 0.2 to 3.0 mm.

76. An encapsulated product according to claim 45 wherein said encapsulated product is in the form of discrete particles or pellets having a diameter of 0.2 to 3.0 mm.

77. The process of claim 53, wherein the encapsulated product is in the form of discrete particles or pellets having a diameter of 0.2 to 3.0 mm.

78. An encapsulated product as claimed in claim 1 wherein said protein component comprises milk protein.

79. An encapsulated product as claimed in claim 1 wherein said protein component comprises a protein concentrate.

80. The method of claim 28 wherein the starch component comprises at least one selected from the group consisting of pregelatinized or modified starch, corn starch, wheat flour, rice flour, barley flour, oat flour, and rye flour, and wherein the protein component comprises milk protein.

81. The method of claim 28 wherein the starch component comprises at least one selected from the group consisting of pregelatinized or modified starch, corn starch, wheat flour, rice flour, barley flour, oat flour, and rye flour, and wherein the protein component comprises a protein concentrate.

82. The method of claim 28, wherein the starch component comprises a high gluten content flour and wherein the protein component comprises milk protein.

83. The method of claim 28, wherein the starch component comprises a high gluten content flour and wherein the protein component comprises a protein concentrate.

84. The method of claim 28, wherein the starch component comprises durum wheat flour and wherein the protein component comprises milk protein.

85. The method of claim 28, wherein the starch component comprises durum wheat flour and wherein the protein component comprises a protein concentrate.

86. The method of claim 28 wherein the starch component comprises meal and wherein the protein component comprises milk protein.

87. The method of claim 28 wherein the starch component comprises meal and wherein the protein component comprises protein concentrate.