HK1064260B - Non-dairy containing milk substitute products - Google Patents

Description

Non-dairy products containing milk substitutes

Technical Field

The present invention relates generally to non-dairy cereal dispersions prepared by enzymatic hydrolysis and more particularly to non-dairy oat dispersions prepared by synergistic enzymatic hydrolysis and products produced therefrom, e.g., non-dairy ready-to-use milk substitutes, yogurt, ice cream, and the like.

Background

The beneficial effects of dietary fiber on health are well known. For this reason, there is an increasing interest in food products made from cereals such as oats and barley. In many respects, oats provide more health benefits than other grains.

Oats have higher protein and fat contents than other grains, and in addition, the proteins in oats have a higher food value than those found in other grains. Oat groats also have a higher beta-glucan content which is believed to lower serum cholesterol levels in hypercholesterolemic individuals. Since elevated serum Cholesterol levels are associated with increased risk of heart disease, it is important to be able to include higher β -glucan foods in the daily diet (as disclosed in "Consumption of Oat Milk for 5 Weeks by Free-Living people with moderate Hypercholesterolemia reduces serum Cholesterol and LDL Cholesterol (Condition of Oat Milk for 5 Weeks) (5 Weeks lower Serum Cholesterol and LDL Cholesterol in Free-Living Men with hypercholesteremia), 1999, Nutrition & Metabolim 43: 301-. In addition, oats contain high levels of soluble fiber (which is mostly beta-glucan), and foods containing soluble fiber also exhibit reduced serum cholesterol levels. Oats also have lower carbohydrate content than other comparable cereals, containing considerable proportions of mono-and polyunsaturated fats, as well as many essential amino acids and minerals.

In oats, most of the nutrients are distributed fairly evenly throughout the whole oat kernel, while in other grains, the nutrients are often concentrated in specific parts of the grain. This means that when oats are used, the whole grain can be used to make a variety of products, as long as the husk is removed.

The nutritional value of oat components has prompted the introduction of oats, or portions thereof, into a variety of different food products. For example, us patent 4,996,063(g.f. inglett) discloses the preparation of a water-soluble dietary fibre composition by treating a crushed oat product with an alpha-amylase. The alpha-amylase acts to thin the oat starch and therefore any alpha-amylase may be used. The resulting powdered dietary fiber composition is used as a food additive, such as a fat substitute. However, these products not only lack the desired aroma of natural oats, but also lose the pleasing natural flavor of oats.

U.S. patent No. 5,686,123 (issued to l.lindahl et al) discloses a homogeneous stable cereal suspension having the flavor and aroma of natural oats. The disclosed cereal suspension is prepared by treating a suspension of oats in a first step of enzymatic treatment with a beta-amylase free from glucanase activity and protease activity, which specifically produces maltose and maltodextrin units. The suspension is then treated in a second enzymatic treatment with an alpha-amylase free from glucanase and protease activities, which specifically produces maltose units. The oat suspension is a milk-like product that can be used as a milk substitute, especially for people with poor lactose tolerance. It can also be used as a main ingredient or additive in the manufacture of ice cream, oatmeal gruel, yogurt, milk shakes (milkshake), health drinks and desserts. However, this method wastes time by sequentially using different hydrolytic enzymes for treatment, thereby increasing production costs. Furthermore, sequential enzyme treatments eliminate the positive synergistic effects that can occur when enzymes are used simultaneously. In addition, the overall viscosity and/or sugar content of the cereal suspension cannot be effectively controlled or manipulated.

In view of these shortcomings, there is a need for a cereal dispersion comprising a ready-to-use, non-dairy whole milk substitute and consumer products prepared therefrom that can be prepared in a more cost-effective and timely manner using an enzyme preparation suitable for cereal starch hydrolysis while producing a nutritional, lactose-free cereal dispersion that retains the flavor and aroma characteristics of the native cereal, and whose viscosity, sugar content, and overall texture can be adjusted or modified to give a preferred end product while maintaining the important cholesterol-lowering characteristics.

Summary of The Invention

The present invention is directed primarily to non-dairy products containing milk substitutes. It is therefore a main object of the present invention to provide a non-dairy cereal dispersion prepared by hydrolysing cereal starch with an enzyme preparation in a more cost-effective and timely manner.

Another object is to produce a nutritional non-dairy lactose-free cereal dispersion that retains the flavor and aroma characteristics of natural cereals.

It is another object of the invention to produce a cereal dispersion whose viscosity, sugar content and overall texture can be controlled or manipulated by varying the relative amounts of enzymes used, while maintaining a high level of native sugars, proteins and beta-glucans which have cholesterol-lowering properties.

It is another object of the present invention to provide ready-to-use and consumption non-dairy milk substitute oat milks, each having a sugar and maltodextrin composition and viscosity values associated with the enzyme preparation used, wherein the oat milks can be used directly for drinking and cooking in place of dairy milks or can be further processed for the production of a range of products including concentrated and powdered products, particularly ready-to-use products such as ice cream and yogurt and the like.

These objects are met by a non-dairy cereal dispersion comprising a cereal substrate suspension and an enzyme composition for enzymatic hydrolysis of components in the cereal substrate suspension, wherein the heat-treated, enzyme-modified cereal comprises intact beta-glucans, proteins and natural sugars. The preparation method of the non-dairy cereal dispersion comprises the following steps:

(i) providing a cereal suspension;

(ii) providing a starch degrading enzyme composition lacking β -glucanase and protease activity but comprising an α -amylase and a β -amylase; and

(iii) treating a grain suspension with an enzyme composition by simultaneously introducing an alpha-amylase and a beta-amylase to the grain suspension to provide:

(a) the enzymatic hydrolysis is accelerated, and

(b) the amount of enzyme used is reduced compared to the larger amount required for the enzyme introduced successively.

In one embodiment of the invention, the ready-to-use product is an ice cream product, which is prepared by the steps comprising:

a) melting 1-15% w/w vegetable fat;

b) adding 0.1-10% w/w emulsifier to the molten fat;

c) heating the fat/emulsifier mixture to 60-80 ℃ to dissolve the emulsifier;

d) adding sucrose, glucose syrup and glucose, each at 1-10% w/w, to the emulsified fat to form a fat/sugar mixture;

e) adding 1-15% w/w of the fat/sugar mixture of step (d) to the modified oat cereal suspension to form a fat/oat/sugar mixture;

f) pasteurizing said mixture at a temperature of 70-90 ℃, and

g) freezing the pasteurized mixture.

The method of preparing a non-dairy, ready-to-use milk substitute cereal dispersion containing intact beta-glucan, protein and natural sugars also includes the steps of:

(i) providing a de-hulled and heat treated oat suspension having an oat content of about 5% to 20% w/w in water;

(ii) providing a starch degrading enzyme composition lacking beta-glucanase and protease activity but comprising alpha-amylase and beta-amylase, and

(iii) treating the grain suspension with an enzyme composition by simultaneously introducing an alpha-amylase and a beta-amylase into the grain suspension to provide:

(a) the enzymatic hydrolysis is accelerated, and

(b) the amount of enzyme used is reduced compared to the amount required for the successive introduction of enzyme,

thereby maintaining the natural flavor and aroma of the oat cereal.

The non-dairy, ready-to-use cereal dispersions discussed above can be consumed in place of dairy products, and can also be used in recipes for cooking and producing other non-dairy or dairy-containing products, such as yogurt, ice cream, and other desserts. These products will be characterized as thick, creamy, homogeneous dispersions, all containing intact beta-glucan, protein and native sugars, wherein the oat dispersion or suspension contains about 0.1-5.0FAU (alpha-amylase activity unit as defined below) of alpha-amylase and about 1400-1600DP ° units (beta-amylase activity unit as defined below) of beta-amylase, wherein at most only 40% of the oat starch is converted to maltose.

Non-dairy cereal suspensions may also be used to produce a milk fat dispersion having a low viscosity and comprising intact beta-glucan, protein and natural sugars, wherein the oat suspension comprises about 5.0-10.0FAU of said alpha-amylase and about 1400-1600DP of said beta-amylase, wherein more than 40% of the oat starch is converted to maltose.

In all non-dairy, ready-to-use milk substitute oat dispersions, alpha-amylase and beta-amylase are introduced simultaneously to the oat suspension to provide shorter enzyme treatment times and reduce the amount of enzyme required.

The method of producing a cereal dispersion with improved homogeneity and stability may also comprise the step of performing at least one finishing process on the enzymatically treated non-dairy cereal dispersion and the products produced thereby, such as ice cream, culinary cream, creamy flavoured drinks, yoghurt and the like.

The finishing step may be used to extend the shelf life of the cereal suspension or other off-the-shelf product, including removal of coarse particles by centrifugation or decantation; homogenizing the enzyme-treated suspension; and/or subjecting the product to ultra high temperature treatment (UHT), as disclosed in food engineering and Daisy technology, H.G.Kessler, Verlay A.Kessler, 1981, Chapter 6, page 139-. After UHT treatment, the product can be aseptically packaged. Other representative methods of extending shelf life include pasteurization and refrigeration until use; alternatively the final product may be evaporated and subsequently spray dried to give a stable powder. Preferably, the dispersion prepared from the enzyme-treated suspension is homogenized, UHT treated and aseptically packaged.

The enzyme activity may be stopped or removed from the enzyme treated suspension prior to processing for extended shelf life. Alternatively, the enzyme activity can be stopped during some processes that improve the shelf life of the product, such as UHT treatment.

The non-dairy milk substitute cereal dispersions herein, and in particular the non-dairy milk substitutes likewise described, the viscous oat milk dispersions can be used to prepare non-dairy ice cream. Although these ice creams contain intact beta-glucans, proteins and natural sugars, these products can be enhanced by the addition of nutrients and flavours, thereby improving the quality of the product.

Non-dairy milk substitute cereal dispersions, especially non-dairy milk substitute non-viscous oat milk dispersions, can also be used as nutritional beverages with natural cereal flavors without further additives or further processing. However, if preferred, fruit or other flavor components may be added to enhance flavor and nutritional value.

Other commercially important processes may employ the non-dairy oat milk substitute of the present invention. Representative examples include non-dairy products, oat-based cream, whipped cream, and buttermilk. The preferred cereal dispersion used to produce the cooking cream is a lower viscosity non-dairy oat milk.

These and other features and advantages of the present invention will be better understood with reference to the following description and appended claims.

Description of the preferred embodiments

For the purposes of the present invention, the following terms and expressions appearing in the specification and claims are intended to have the following meanings:

as used herein, "heat-treated oat product" refers to the dehulled and heat-treated grain (small), oatmeal or oat flour described in detail below.

As used herein, "free enzyme" refers to an enzyme that is free to move in suspension and is not limited by capacity or immobilized to a substrate.

As used herein, "immobilized enzyme" refers to free enzyme defined by physical methods of various methods including, but not limited to, semipermeable membranes, hollow fibers, or ultrafiltration membranes.

"FAU" is an acronym for fungal amylase units, and refers to the amount of alpha-amylase required to convert an amount of cereal starch to maltose or maltose syrup under "standardized" conditions. Under the trade name MyclolaseThe supplier Genencor International of alpha-amylase defines FAU as the amount of enzyme converting 1g of soluble starch per hour in the product, which after reaction with iodine has the same absorption at 620nm as the standard colour, at pH 5.0, T30 ℃ and reaction time 15-25 min.

"DP °/ml" as used herein is defined as the enzyme activity unit of β -amylase. Trade name SPEZYME BBAThe beta-amylase supplier Genencor International 1500 defines DP °/ml as the level of glycation power, which is the amount of enzyme contained in a 0.1ml 5% solution of the sample enzyme preparation, which is incubated with 100ml of substrate for one hour at 20 deg.CSufficient reducing sugars were produced to reduce 5ml of the furin's solution.

As used herein, "pre-processed grain suspension" refers to a product that has been previously processed by the process disclosed in U.S. patent No. 5,686,123.

As used herein, "cereal substrate" means a suspension selected from the group consisting of a cereal meal suspension, a pre-processed cereal suspension, and mixtures thereof.

As used herein, "oat flour suspension" refers to a suspension containing oat flour and/or crushed oats.

The invention provides an enzyme preparation for enzymatically hydrolyzing a component of a cereal substrate suspension, comprising at least one hydrolase capable of hydrolyzing alpha-glycosidic bonds. The hydrolase may be selected from the group consisting of beta-amylase, alpha-amylase, amyloglucosidase, pullulanase, and mixtures thereof. Preferably, when the enzyme preparation contains an alpha-amylase or a beta-amylase, it is mixed with at least one other alpha-glycoside hydrolase, more preferably, when two or more enzymes are mixed in the enzyme preparation, the enzymes are introduced into the cereal substrate suspension simultaneously.

In a preferred embodiment of the invention, the enzyme preparation may contain only pullulanase; contains only amyloglucosidase; or several different combinations of hydrolytic enzymes, including: a mixture of beta-amylase and pullulanase; a mixture of beta-amylase, pullulanase and amyloglucosidase; a mixture of beta-amylase and alpha-amylase; and mixtures of alpha-amylase, beta-amylase, and amyloglucosidase. In any of the above enzyme preparations containing one hydrolase alone or in combination with another hydrolase, an isomerase, such as glucose isomerase, may also be present.

In any of the above enzyme preparations containing one hydrolase alone or in combination with another hydrolase, an isomerase, such as glucose isomerase, may also be present.

A preferred embodiment of the invention provides an enzyme preparation comprising an alpha-amylase and a beta-amylase for enzymatic hydrolysis of components in a suspension of a cereal substrate. These enzymes are capable of hydrolyzing alpha-glycosidic linkages. It will be appreciated that the alpha-amylase and beta-amylase are introduced into the cereal suspension simultaneously.

Generally, the cereal added to the cereal meal suspension may be any starting cereal material, including but not limited to oat, barley, rice, wheat, corn, rye, sorghum, triticale and pearl millet. Preferably the cereal is oats. As mentioned above, oat has a characteristic which is considered particularly useful by consumers because it has a high amount of high molecular weight β -glucan, which is a natural hydrocolloid. In the suspensions produced by enzymatic hydrolysis with the enzyme preparation of the invention, it was found that beta-glucan acts as an intrinsic stabilizer in oats. Thus, the cereal suspension of the invention may act as a thickening, gelatinizing or stabilizing emulsion in a food product.

The cereal suspensions of the present invention can be used in the same application areas as the products disclosed in U.S. Pat. No. 5,686,123, as milk substitutes, and as main ingredients and additives for the production of ice cream, oatmeal gruel, yoghurt, milkshakes and desserts.

All cereal products, regardless of their final state, are initially subjected to the same treatment. Oats and other grains are first dehulled. The dehulled grains are treated with steam to inactivate enzymes inherent in oats, such as lipases and peroxidases. These enzymes have a negative impact on the taste of the final oat product as they promote lipid oxidation. Oats are particularly rich in lipids, especially unsaturated lipids which are sensitive to oxidation. The dehulled and heat treated oat grains (in small quantities) can be used as starting material for the end product or the small quantities can be treated to further produce oatmeal or oat flour. When the small amount is pressed after the second heat treatment, oatmeal (flakes) will be produced. When a small amount of oat is subjected to a second heat treatment, grinding is used instead of pressing to produce oat flour. Wet grinding may stimulate the production of oat milk because it makes the starch more accessible to enzymes. It is advantageous if the oats are finely ground so that they pass through a 0.8-1mm sieve.

Any of these oat products can be used to produce the non-dairy cereal dispersions of the invention as well as the ready-to-use oat milk. For convenience, the use of oats in the form of oatmeal is preferred because they are readily available, large bagged, and stable for storage, but are more economical to use in small quantities.

If the oat flour is produced by dry milling, the dry oat flour is mixed with water to form a solid/liquid suspension. The oats were added while the water was continuously stirred and maintained at 50-53 ℃. Suitably, the weight ratio of coarse powder to water in the slurry or suspension is from about 1: 6 to about 1: 9, which corresponds to about 10 to about 15% w/w of the dry solids content. The suspension was stirred continuously until the meal was completely dispersed. The slurry has a pH of at least 5-8. This pH range has been found to be effective when adding the enzyme preparation of the invention. In this pH range, the enzyme preparation has acceptable catalytic activity and the use of additives to change the pH can be avoided.

To remove the coarse particles, the suspension may be centrifuged or decanted at 350-450G for about 10-15 minutes.

The aqueous oat suspension is then treated with a starch degrading enzyme composition lacking β -glucanase activity and protease activity. The enzyme is modified to produce the physicochemical and organoleptic characteristics required for oat milk. The relative amounts of enzymes such as alpha-amylase and beta-amylase added will depend on the desired viscosity of the final product, as will be described below.

The enzyme preparation of the present invention can convert cereal starch containing both amylose and amylopectin into maltodextrin having a large molecular weight and low molecular weight compounds such as maltotriose, maltose and glucose having various degrees of modification. For example, β -amylase can hydrolyze α -1-4 glycosidic linkages sequentially from the non-reducing ends of amylose and amylopectin to produce maltose, a cleavage product; alpha-amylases can hydrolyze internal alpha-1-4 glucosidic bonds on both amylose and amylopectin, producing a cleavage product maltodextrin; and amyloglucosidase can hydrolyze alpha-1, 4 and 1, 6 glycosidic bonds on the non-reducing end of starch to release glucose molecules. Thus, a combination of hydrolytic enzymes capable of hydrolyzing alpha-glycosidic linkages will provide various ratios of maltodextrin/sugar in the enzymatically treated cereal suspension.

The choice of enzyme and reaction time determines the extent of degradation and the product profile. Different enzyme preparations comprising a combination of at least one alpha-glycoside hydrolase and/or isomerase are used to produce different kinds of mono-and disaccharides. The final product may comprise disaccharides, maltose and monosaccharides, fructose and glucose. For example, a debranching enzyme pullulanase and β -amylase will aggregate large amounts of maltose. Amyloglucosidase and glucose isomerase can produce fructose and glucose.

Cereal starches can be completely converted to low molecular weight compounds, e.g., glucose, by combining, for example, beta-amylase, alpha-amylase, and amyloglucosidase. Whereas fructose will be produced when only glucose isomerase is added to a cereal substrate already containing glucose. Alternatively, enzyme preparations of beta-amylase, alpha-amylase, and amyloglucosidase in combination with glucose isomerase will also produce a product with high levels of fructose.

When both alpha-amylase and beta-amylase are added to the grain suspension simultaneously, the alpha-amylase acts as a catalyst to not only promote the reaction rate of the beta-amylase but also to increase yield. This synergistic effect produces a maltose rich oat milk and allows the production of maltose and maltodextrin units with a lower amount of enzyme in less time than when the enzyme is used alone. Increasing the concentration of alpha-amylase relative to beta-amylase produces increased maltose.

Enzyme preparations whether single enzymes or mixtures of enzymes, the cereal substrate suspension of the invention may be treated by introducing the free enzyme directly into the cereal substrate suspension or by introducing the cereal substrate suspension into a vessel containing the immobilized enzyme.

Generally, free enzymes or cells cannot be reused because they are too small to be filtered and are expensive to recover. The present invention thus accomplishes the elimination of the biocatalytic activity of the free enzyme by denaturing the enzyme.

The effectiveness of using soluble or insoluble immobilized enzymes is in the selective control of the substrate as well as the product by the selectivity of the membrane, many enzymes can be immobilized simultaneously. The immobilized enzyme used in the present invention provides the convenience of loading and processing the cereal meal suspension in a continuous reactor. Advantages of immobilized enzymes include complete recovery of the enzyme from the reaction mixture used in either batch or continuous operation. Thus, the enzyme can be reused without contaminating the final product and without the need to heat the product to denature the enzyme. Also, a greater concentration of immobilized enzyme can be used, as the immobilized enzyme can be recovered and reused, thereby saving reaction time and/or the size of the vessel in which the reaction needs to be carried out. Another advantage is that there is virtually no enzyme present in the final product, so that the enzyme only needs to be approved with food processing aids rather than with additives, even if heating and subsequent enzyme inactivation is not included in the process.

The inventors further contemplate that the enzymes used to prepare the enzyme-modified suspension and/or the homogeneous and stably-enhanced cereal suspension may include enzymes from whole cells, organelles, or even microorganisms used as biocatalysts during fermentation.

In the present invention, all conditions including temperature, pH and addition of other substrates, such as enzyme cofactors or buffers, will determine the activity of the enzyme and the yield and quality of the final product. Enzymes extracted from different sources are known to catalyze the same reaction. For example, the optimum pH of the alpha-amylase from the fungal organism Aspergillus oryzae (Aspergillus oryzae) is 4.7 and the optimum temperature is 50 ℃, whereas the optimum pH of the alpha-amylase from the bacterium Bacillus licheniformis (Bacillus licheniformis) is 7.5 and the optimum temperature is 90 ℃. It will therefore be appreciated that the operating conditions, including enzyme amount, slurry temperature, agitation time and pH, are optimised to obtain a suitable viscosity of the final product. The techniques used to determine the optimum parameters are well known to those skilled in the art and are widely used.

The cereal substrate suspension of the invention is treated with an enzyme preparation at a carefully controlled operating temperature. The temperature is chosen so that the enzyme performs with both a fast hydrolysis rate and good enzyme stability. Generally, temperatures of about 40 ℃ to below the temperature at which the enzyme or enzyme composition is denatured, preferably about 50 ℃ to 90 ℃ depending on the enzyme, are employed. At lower temperatures, the enzyme activity may be lower, while at higher temperatures, the enzyme stability may be lower. Therefore, the temperature at which the reaction is catalysed is selected to optimise the production of the final product whilst maintaining the stability of the enzyme preparation. The invention is also applicable to thermostable starch degrading enzymes, in which case the operating conditions can be adjusted to suit the characteristics of these enzymes.

A hydrolase and/or a combination of hydrolases is introduced into the cereal substrate suspension in an amount sufficient to hydrolyze the alpha-glycosidic linkages in the substrate suspension components to provide a final product of a desired viscosity. The combination of enzymes and the amount of each specific enzyme yields suspensions containing different sugars and different amounts of the various sugars. High concentrations of low molecular weight sugars, such as maltose and glucose, in the final product result in a low viscosity cereal dispersion. In contrast, high concentrations of high molecular weight maltodextrin produce a viscous product that can be used in soups or yogurts because of their greater density.

Thus, varying the type and amount of enzyme in the mixture will produce a specifically designed product. The particular composition of the enzyme employed helps to standardize the reaction process as compared to varying reaction times, or other reaction parameters that do not affect the final product to a greater extent, and thus the final product is related to the enzyme composition.

In the practice of the present invention, it is generally advantageous to use about 1-100ml of enzyme preparation per kg of oat or other cereal material making up the cereal substrate suspension. The suspension may be treated with an enzyme preparation selected to produce an end product having a viscosity of about, e.g., water or about 10mPas to about several hundred mPas, a shear rate of about 500-^-1. Representative enzymes are alpha-amylases, which convert cereal starch into maltose or maltose syrup. The activity of alpha-amylase is defined as FAU (fungal amylase units). FAU is defined by the alpha-amylase supplier Genencor International under the trade name Myclolase, as discussed in the definitions section aboveThe theory is as follows. NovoNordisk under the trade name FungamylAlpha-amylase was provided and FAU was defined as the amount of enzyme that degraded 5.26g of soluble starch per hour at pH 4.7 and reaction time 7-20min (Merck, ammonium soluble erg.b.6, lot 9947275).

The sweetness of the cereal milk produced by the enzyme-modified oat suspension can be adjusted and/or manipulated by using a suitable enzyme preparation. In fact, the enzyme preparation of the invention can be introduced in several steps to tailor the final product. For example, enzyme preparations containing both alpha-amylase and beta-amylase can produce high levels of maltose. Maltose can be converted to glucose and fructose by a second treatment with an enzyme preparation containing amyloglucosidase and/or glucose isomerase. The production of glucose, and in particular fructose, is sweeter than a suspension containing primarily maltose. The fructose-containing suspension has the significant advantage that fructose has no adverse effects on diabetic patients.

The particular type of sugar affects not only the characteristics of the suspension but also the organoleptic characteristics of the product produced with this suspension. By varying the sugar type, it is possible to adjust the functional properties of the suspension, such as viscosity, nutritional properties and the ratio of the sugar content, to meet the requirements of the end product.

In the enzymatically modified cereal suspension, or in the enzymatically treated cereal suspension, the enzymatic activity may be disrupted or stopped by any method known to the person skilled in the art, including denaturation, centrifugation, chromatographic techniques and/or separation of the suspension from the immobilized enzyme. Preferably, the enzymatic reaction is terminated by heating the cereal suspension to at least 80 ℃, more preferably to between 80 and 90 ℃. Higher temperatures are required to inactivate enzymes at lower water contents than at higher water contents. At higher humidity, lower temperatures are sufficient to achieve the same degree of enzyme inactivation. Alternatively, the enzyme activity may be interrupted/terminated in the final step of extending the shelf life of the product.

Using the cereal suspension of the invention, a homogeneous and improved stability cereal dispersion is prepared by treating the suspension with the enzyme preparation provided by the invention, which has the aroma and taste of natural cereals and contains intact beta-glucans, proteins and natural sugars.

Representative final processing steps may include finishing treatments such as removal of coarse particles by centrifugation or decantation; homogenizing the enzyme-treated suspension at a temperature of about 42-45 ℃ and a pressure of about 200-250 bar; or subjecting the product to ultra-high temperature treatment (UHT), as disclosed in Food Engineering and Daisy technology, H.G.Kessler, Verlay A.Kessler, 1981, Chapter 6, pp 139-. After UHT treatment, the product can be aseptically packaged. Insoluble material was removed by centrifugation, otherwise it had a gritty feel. The homogenate improves the smooth mouthfeel and prevents the occurrence of precipitates due to long-term storage. Other methods of extending shelf life may include pasteurization to kill spoilage microorganisms, thereby extending shelf life, refrigeration until use; alternatively, the product may be evaporated and subsequently spray dried to give a microbiologically stable powder, facilitating handling and transport.

In a more preferred embodiment, the cereal substrate suspension is a cereal meal suspension. The cereal meal suspension is made by dry or wet milling cereal pieces, or heat or water treating the cereal to meal and suspending the cereal meal in water. Alternatively, the suspension is centrifuged or decanted to remove coarse fiber particles prior to treatment with the enzyme preparation.

For convenience, the preparation of the grain meal suspension is based on the production and sale of pre-gelatinized oatmeal that retains the original taste and aroma of oats. The oatmeal is milled into oatmeal or oatmeal by whole milling, dry milling or wet milling. In dry milling, the oatmeal is suspended in water, preferably at a temperature of 50-65 ℃. In wet milling, the water temperature used is likewise preferably from 50 to 65 ℃. Better results are obtained if the water is deionized.

For the majority of the starch contained in the cereal meal, heating the suspension to 50-65℃ gelatinizes the cereal starch and is therefore more easily hydrolysed. However, some oats contain starch that is highly tolerant, and that does not gelatinize at these temperatures and is therefore not readily hydrolyzed by the enzyme preparations of the present invention. In this case, it is advantageous to first hydrolyze the non-resistant starch with the enzyme preparation of the invention in a first enzymatic treatment and then to subject the suspension to a higher temperature, preferably above 100 ℃, in order to gelatinize the resistant starch. The suspension is then cooled to an operable temperature and standard conditions. The suspension is then treated with the enzyme preparation of the invention. This process will allow for more complete hydrolysis of almost all of the starch in the cereal meal suspension, including the tolerant starch.

In a further embodiment of the invention, a pretreated cereal suspension may be used. In a first step of the enzymatic treatment specifically producing maltose units and without glucanase and protease activity, the cereal meal suspension is treated with a beta-amylase to a viscosity of 3-0.1Pas at a shear rate of 10-100s^-1The process is carried out. Then in a second step of an enzymatic treatment specifically producing maltose units and free of glucanase and protease activities, the suspension is treated with an alpha-amylase to a viscosity of less than 0.5Pas at a shear rate of 10-100s^-1The process is carried out. The pre-treated cereal suspension may then be further treated with the enzyme preparation of the invention. Alternatively, the pre-treated cereal suspension may be homogenised or subjected to UHT treatment.

The invention will be described in more detail in the following non-limiting examples.

Example 1

The pregelatinized oatmeal is wet milled at about 52-63 ℃ for preparing a suspension, wherein the concentration of the milled suspension in the water is about 10-15% w/v. The enzyme preparation of the invention, containing barley beta-amylase (Genencor Intl., Rochester, NY, USA; or Rhodia Ltd, Cheshire, UK) and a debranching enzyme pullulanase such as Promozyme (Novo Nordisk, Bagsvaerd, Denmark), is added to the cereal meal suspension at a concentration of about 2ml per kg of oats at about 58-61 ℃. The enzyme concentration in the enzyme preparation is respectively per ml about 500-1000DP ℃ and about 150-300PU (pullulanase units). Allowing the enzyme preparation to act for 1-2 hours, or until the viscosity of the suspension has dropped to about 20-40mPas, with a shear rate of 700s^-1. The obtained product contains a large amount of maltose. Most of the starch (about 60% of oats) is converted to maltose. The suspension is then heated to about 85-90 ℃ to inactivate the enzyme. The product was decanted to remove excess insoluble fiber and homogenized. Alternatively the product can be UHT treated and aseptically packaged, pasteurised and refrigerated until use, or evaporated and subsequently spray dried to give a stable powder.

Example 2

The pregelatinized oatmeal was milled as in example 1. An enzyme preparation of the invention comprising barley beta-amylase (Genencor Intl., Rochester, NY, USA; or Rhodia Ltd Cheshire, UK), a debranching enzyme pullulanase such as Promozyme (Novo Nordisk, Bagsvaerd, Denmark) and an amyloglucosidase such as AMG (Novo Nordisk, Bagsvaerd, Denmark) or Optidex (Genencor Intl., Rochester, NY, USA) is added to the oat flour suspension at a concentration of about 3-4ml per kg of oat at about 58-61 ℃. The concentrations of these enzymes in the enzyme preparation were about 400-700DP, about 100-200PU (pullulanase units) and about 90-110AGU, respectively, per ml. Allowing the enzyme preparation to act for about 1-2 hours, or until the viscosity of the suspension has dropped to about 20-40mPas, with a shear rate of 700s^-1. The obtained product contains a large amount of glucose. Finally, the suspension was heated and treated as in example 1.

Example 3

The pregelatinized oatmeal was milled as in example 1. An enzyme preparation of the invention comprising a mixture of a β -amylase (Genencor Intl., Rochester, NY, USA; or Rhodia Ltd, Cheshire, UK) and an internal-acting α -amylase such as Fungamyl (Novo Nordisk, Bagsvaerd, Denmark) or Mycolase (Genencor Intl., Rochester, NY, USA) is added to the cereal meal suspension at a concentration of about 2ml per kg of oats at about 54-57 ℃. The concentrations of these enzymes in the enzyme preparation were about 1400-1600DP DEG per ml andabout 30-70FAU (amylase units). Allowing the enzyme preparation to act for about 1 hour, or until the viscosity of the suspension has dropped to about 20-40mPas, with a shear rate of about 700s^-1. Most of the oat starch (60-70%) is converted to maltose and the rest is present as maltodextrin (step 1). Then (step 2), another exo-acting enzyme, such as amyloglucosidase AMG (Novo Nordisk, Bagsvaerd, Denmark) or Optidex (Genencor Intl., Rochester, NY, USA), is added at about 600AGU (amyloglucosidase units) per kg of oats. When the desired amount of glucose has been produced, the reaction is terminated. For example, 30 minutes after the addition of amyloglucosidase (glucoamylase), the suspension contains equal amounts of maltose and glucose, and the maltose content is 50% of the suspension of step 1. The maltose content in step 1 is high and amyloglucosidase rapidly hydrolyzes the substrate. As maltose content decreases, maltodextrin becomes the preferred substrate and hydrolysis also increases. When complete conversion is reached, all starch is converted to glucose. Finally, the suspension was heated and treated as in example 1.

Example 4

The pregelatinized oatmeal was milled as in example 1. An enzyme preparation of the invention comprising a mixture of barley beta-amylase (Genencor Intl., Rochester, NY, USA; or Rhodia Ltd, Cheshire, UK), an alpha-amylase such as Fungamyl (Novo Nordisk, B agsvaerd, Denmark) or Mycolase (Genencor Intl., Rochester, NY, USA) and an amyloglucosidase such as AMG (Novo Nordisk, Bagsvaerd, Denmark) or Optidex (Genencor Intl., Rochester, NY, USA) is added to the suspension in an amount of about 3-4ml per kg of oats at about 54-57 ℃. The concentrations of these enzymes in the enzyme preparation were about 700-900DP, about 1-35FAU (. alpha. -amylase units) and about 200-350AGU, respectively, per ml. Allowing the enzyme preparation to act for about 1-2 hours, or until the viscosity of the suspension has dropped to about 20-40mPas, with a shear rate of 700s^-1. Finally, the suspension was heated and treated as in example 1.

Example 5

Oat suspensions prepared according to U.S. Pat. No. 5,686,123 were treated with an enzyme preparation of the present invention containing barley beta-amylase (Genencor Intl., Rochester, NY, USA; or Rhodia Ltd, Cheshire, UK) and a debranching enzyme pullulanase such as Promozyme (NovoNordisk, Bagsvaerd, Denmark) at a concentration of about 2ml per kg of oats. Alternatively, the suspension is treated with a debranching enzyme, e.g., a pullulanase, such as Promozyme (Novo Nordisk, Bagsvaerd, Denmark) at a concentration of about 800PU per kg of oats. Other conditions were the same as in example 1. The resulting product is high in maltose and substantially free of maltodextrin.

Example 6

Oat suspensions prepared according to U.S. Pat. No. 5,686,123 were treated with the same enzyme preparation as in example 2, or with amyloglucosidase as in example 3 (step 2). As the hydrolysis proceeds, the maltodextrin content of the product decreases and the glucose content increases.

Example 7

To any of the products of examples 2, 3, 4 and 6, i.e.to the glucose containing product, an enzyme preparation of the invention containing amyloglucosidase (about 50-60AGU per ml), such as AMG (Novo Nordisk, Bagsvaerd, Denmark) or Optidex (Genencor Intl., Rochester, NY, USA), and glucose isomerase (about 3000U per ml) is added at a concentration of about 18-70ml per kg oat, or only glucose isomerase at a concentration of about 50,000-200,000GIU (glucose isomerase units), such as Spezyme GI (Genencor Intl., Rochester, NY, USA) or Sweetze (Novo Nordisk, Bagsvaerd, Denmark). Within 2 hours, 25% of the glucose was converted to fructose.

Example 8

A ready-to-use, non-dairy, thick oat milk was prepared as follows. About 10-15% w/w oat cereal meal is suspended in water heated to 50-60 ℃. The meal may be dry or wet milled oat, or heat or water treated meal. For convenience, the cereal meal suspension is prepared by using pre-gelatinized oatmeal which is commercially available. To more easily hydrolyze most of the starch in the cereal meal, the suspension is maintained at 50-65 ℃ to gelatinize the cereal starch. The enzyme preparation of the invention containing a beta-amylase (Genencor Intl., Rochester, NY, USA; or Rhodia Ltd, Cheshire, UK), and an internal-acting alpha-amylase such as Fungamyl (Novo Nordisk, Bagsvaerd, Denmark) or Mycolase (Genencor Intl., Rochester, NY, USA) is then added to the aqueous oat suspension at an enzyme concentration of about 1-3ml per kg of oat at about 54-64 ℃. The alpha-amylase and beta-amylase are added simultaneously while the suspension is kept under constant stirring. The temperature of incubation was maintained at 53-55 ℃.

The simultaneous addition of alpha-amylase and beta-amylase accelerates enzymatic hydrolysis and uses a lower amount of enzyme than when the enzymes are added separately. The concentrations of these enzymes in the enzyme preparation were about 1400-1600DP ℃ and about 0.5-2FAU/ml, respectively. These enzyme preparations were allowed to act on oat cereals for approximately 2 hours, or until the viscosity of the emulsion was 60,000cP, measured at 10% concentration and 4 ℃ with a Brookfield viscometer at 0.3 rpm. About 40% of the starch is converted. Thus, the product is very viscous due to the high content of high molecular weight maltodextrin.

Or at this point the enzymatically treated milk product is homogenized at a pressure of 200bar (homogenization should be carried out in the range of 160-250 bar) and a temperature of 72-75 ℃. The non-dairy oat milk may then be subjected to indirect evaporation at 137-138 ℃ for 3-4 seconds to sterilize the suspension. This sterilization process kills bacteria and spore-forming vehicles and inactivates the added enzymes prior to aseptic packaging of the product.

The resulting high viscosity oat milk is uniform and stable, contains intact beta-glucan and protein, retains the taste and flavor of natural oats, has excellent freeze/thaw, water retention, thickening, and organoleptic (fatty mouthfeel) properties, and is useful as a base material for preparing, or as other non-dairy oat milk suspension products. The combined properties exhibited by this oat product make it ideal for use in frozen desserts or ice cream, for example.

Example 9

Ready-to-use non-dairy oat milk suspension the whole milk cow milk substitute has a low viscosity and was prepared according to the method of example 8 except that the concentration of alpha-amylase was about 6-8FAU per ml when the concentration of beta-amylase in the enzyme preparation was maintained at about 1400 ℃ 1600DP, resulting in a low yield of maltodextrin relative to the maltose yield, resulting in a low viscosity product. The milky oat milk suspension can be used for providing delicious and nutritious non-dairy beverages or as a main ingredient for preparing cheese, beverages and ice cream.

Example 10

As an example of how a high viscosity non-dairy oat milk suspension can be used as a frozen product, a natural fruit flavored ice cream was prepared. A10% w/w oat suspension was prepared according to example 8. Then 8% w/w melted vegetable fat, e.g. Akomix (from Karishamns AB, Karshamn, Sweden), 0.4% w/w emulsifier, e.g. distilled monoglycerides (Danisco Cultor, norkoeping, Sweden) are added separately. The fat/emulsifier mixture is heated to above 70 ℃ to dissolve the emulsifier. When the emulsifier dissolved, 7% w/w sucrose and 8% w/w glucose were added to the emulsified fat. The emulsified melted fat/sugar mixture is then added to the oat suspension. Finally the mixture was pasteurized at 80 ℃ for 25 seconds.

Alternatively, the mixture may be homogenised at 200bar before cooling overnight.

Flavorings such as vanilla or fruit, such as blueberry or pineapple puree, may be added to the cooled mixture. After partial freezing of the mix, air was incorporated into the mix to produce an overrun value of approximately 80%, where overrun is the ratio of the volume of ice cream over the volume of unfrozen mix. The ice cream is hardened at a temperature below-20 ℃ prior to consumption.

The ice cream prepared by using the high viscosity oat milk suspension of example 8 is able to retain injected air bubbles, which results in a frozen product, e.g. cream flavored/mouthfeel ice cream. Because the product also has unexpected freeze-thaw stability, it does not require stabilizers or additional protein additions.

Example 11

A concentrated nutritious tasty fruit/oat milk beverage was prepared using the low viscosity non-dairy oat milk suspension of example 9 by adding 10% w/w of the required fruit concentrate to this oat milk suspension. The mixture was then pasteurized at 90 ℃ for 13 seconds and homogenized at 200bar while maintaining at 90 ℃. The mixture is then poured into a separate storage container, such as a glass bottle. Alternatively, the product may be cooled to about 4-6 ℃ and then injected into the container in a sterile manner. A nutritious and palatable beverage is obtained without the need for additional sweeteners, acids, stabilizers or flavors.

Example 12

Non-dairy oat ice cream prepared using the low viscosity oat milk of example 9 was prepared by melting 8% w/w of a vegetable fat such as Akonix (from Karishamns AB, Karshamn, Sweden) and adding 0.4% w/w of an emulsifier such as distilled monoglycerides (from Danisco Cultor, Morrkoeping, Sweden) to the vegetable fat. The fat/emulsifier mixture was heated to dissolve the emulsifier before adding 5% w/w sucrose, 5% w/w glucose syrup and 5% w/w glucose. 8% by weight of the fat/sugar mixture was added to a 10% w/w oat milk suspension. The final mixture was then pasteurized at 80 ℃ for 25 seconds.

Alternatively, at this point, the mixture may be homogenised at 200bar prior to cooling and addition of flavour and/or fruit.

The mixture is then partially frozen, air is injected into the semi-frozen mixture, and finally hardened at a temperature below-20 ℃.

Example 13

A non-dairy oat-based cream product containing the oat milk of example 9 was prepared by thawing a mixture of 50% w/w canola oil and 50% w/w palm oil at 70 ℃. To the melted oil mixture 0.4% w/w emulsifier is added, e.g. distilled monoglycerides. In a separate step, 0.05% w/w salt was added to the non-sticky oat milk suspension. The emulsified fat and salted oat milk were then homogenized with a secondary homogenizer at 200 bar. The product is then aseptically packaged, preferably 3 dl.

The non-dairy beta-glucan suspension is ready for use in the desired preparation of the creamer.

Claims (10)

1. A non-dairy or dairy containing ready-to-use product selected from milk replacers, yoghurt, ice cream, oat gruel, milkshakes and desserts, culinary cream, whipped cream, fruit flavoured drinks or other flavoured drinks, said product containing as a main ingredient a modified oat cereal suspension prepared by the steps of:

(i) providing an oat grain substrate suspension;

(ii) providing a starch degrading enzyme composition lacking β -glucanase and protease activity but comprising an α -amylase and a β -amylase;

(iii) treating the oat cereal substrate suspension with the starch-degrading enzyme composition while adding alpha-amylase and beta-amylase, thereby providing a hydrolyzed cereal suspension;

(iv) adjusting or modifying the viscosity, sugar content and overall texture of the hydrolyzed cereal suspension for a desired end product, and

(v) (iv) subjecting the product of step (iv) to at least one finishing step.

2. The ready-to-use product of claim 1 wherein the product is a non-dairy containing whole milk substitute characterized by a lower yield of maltodextrin relative to maltose.

3. The ready-to-use product of claim 1 wherein the product is an ice cream or frozen dessert prepared from the modified oat grain suspension having a higher viscosity.

4. The ready-to-use product of claim 3, prepared by the steps comprising:

a) melting 1-15% w/w vegetable fat;

b) adding 0.1-10% w/w emulsifier to the molten fat;

c) heating the fat/emulsifier mixture to 60-80 ℃ to dissolve the emulsifier;

d) adding sucrose, glucose syrup and glucose, each at 1-10% w/w, to the emulsified fat to form a fat/sugar mixture;

e) adding 1-15% w/w of the fat/sugar mixture of step (d) to the modified oat cereal suspension to form a fat/oat/sugar mixture;

f) pasteurizing said mixture at a temperature of 70-90 ℃, and

g) freezing the pasteurized mixture.

5. The ready-to-use product of claim 1, wherein the product is buttermilk prepared from the modified oat cereal suspension.

6. The ready-to-use product of claim 1 wherein the product is a fruit flavored beverage.

7. The ready-to-use product of claim 1, wherein the product is a flavored beverage.

8. The ready-to-use product according to claim 1 wherein the modified oat cereal suspension is an oat suspension containing 5-20% w/w oat in water.

9. The ready-to-use product of claim 1 wherein the modified oat grain suspension comprises 0.1-5.0FA units of the alpha-amylase and 1400-1600DP ° units of the beta-amylase and wherein up to 40% of the oat starch is converted to maltose.

10. The ready-to-use product of claim 1 wherein the modified oat grain suspension comprises 5.0-10.0FA units of the alpha-amylase and 1400-1600DP ° units of the beta-amylase.