GB2113521A - Protected feedstuffs and their production - Google Patents

Abstract

Feedstuffs comprise a nutritional material such as a high protein dietary supplement, carbohydrate, mineral or vitamin, protected by a coating of an edible water insoluble fatty acid salt. Such feedstuffs are capable of resisting the action of bacteria in the rumen of ruminant animals. This water insoluble salt may be formed in situ by reaction of a water-soluble fatty acid salt with a compound capable of forming a precipitate therewith, e.g. a calcium salt. Alternatively, the fatty acid salt may be formed by direct reaction of reaction of the fatty acid with e.g. calcium oxide, and the nutritional material may also be dispersed in the fatty acid salt while the latter is in the molten state.

Description

SPECIFICATION Protected feedstuffs and their production This invention relates to protected feedstuffs and their production.

Modern husbandry requires that under some circumstances ruminant animals should be fed a proportion of their dietary requirement in the form of nutrients that are not degraded in, or do not interfere with, the normal processes of rumen fermentation.

Such nutrients include in particular protein and fats and other nutrients which are essential for healthy growth and meat or milk production such as vitamins.

In the case of fats (whether free fatty acids or triglycerides) it is known that feeding amounts above 500 grams per day to a mature cow normally results in interference in the normal process of rumen fermentation. Triglycerides or free fatty acids can physically coat the fibrous or cellulose material in the rumen and thus prevent cellulitic bateria from breaking the material down. This effect can alter the energy metabolism of the animal and reduce the quantity of milk fat secreted by the lactating animal.

Free fatty acids are also known to be toxic to certain bacteria in the rumen and this, too, can alter the fermentation pattern in the rumen, with consequential effects on total feed digestibility.

Lipids encapsulated in formaldehyde-treated casein have been shown to be protected from fermentation in the rumen and to give a significant increase in milk yield and milk fat production in lactating cows, while at the same time increasing the overall efficiency of energy metabolism. However, it is uneconomical to use casein which is itself derived from milk and the processing of casein is expensive.

Also, doubts have been expressed about the safety of using aldehydes in this context because of the possibility of residues being found in the milk.

In addition, during the normal process of rumen fermentation, unsaturated fats fed in the free form are hydrogenated. It is sometimes desirable to feed ruminant animals with unsaturated fats (e.g. soya oil) in such a form that the unsaturated fatty acids are either deposited in depot fat or secreted in milk fat. Milk produced from cows in this way has been shown to have benefits in terms of butterfat having a modified fatty acid composition and a lower melting point, and hence better spreading characteristics.

In the case of protein metabolism, it is known that, at certain times during the period of growth and development and subsequent lactation in the case of a high-yielding dairy cow, the rumen is not capable of producing sufficient microbial protein to meet the animal's fuil requirements for maximum growth or maximum production of milk. Young ruminant animals are frequently fed diets containing a high proportion of rumen degradable protein, which is rapidly broken down and formed into microbial protein. When, however, a proportion of undegradable protein is added to the diet, there is frequently an improvement in growth rate and feed conversion efficiency as a result of the undegradable protein by-passing the rumen.

It is also desirable to be able to add fats to compounded feeding stuffs for both ruminant and non-ruminant animals to increase the energy density of the feedstuff. It is not normally possible to achieve high fat levels (above 10%) in conventionally pelleted compound feedstuffs when using free fats as the subsequent pellet quality is often poor. Liquid fats are also difficult to handie.

The present invention provides a means whereby lipid and protein feed materials can be protected from breakdown or degradation in the rumen, but are subsequently available for digestion. Feedstuffs protected in this manner can be produced easily in the form of a free4lowing powder, as pellets, or as a solid block, even when their lipid content is derived from a liquid lipid. Incorporation of the new feed stuffs into ordinary feedstuffs presents no difficulty and their valuable effect upon the nutrition of ruminant animals has been demonstrated.

The feedstuff of the present invention comprises a nutritional material protected in particular against fermentation in the rumen by dispersion in a protective coating of an edible water-insoluble fatty acid salt. The nutritional material may be a protein, carbohydrate, mineral, dietary supplement of vitamin, but the invention is most advantageously applied to the coating of proteins which may be degraded in, or interfere with, digestion in the rumen, and to the protection of dietary supplements which cannot pass the rumen without degradation.

Thus, it is particularly advantageous to produce in accordance with the present invention feedstuffs comprising a good quality animal or vegetable protein. Examples of the latter are grass meal, lucerne meal, field beans, pea protein, coconut meal, cottonseed, groundnut, linseed, palm kernel, detoxified soya bean, defatted soya bean meal, sunflower seed, rape seed, fishmeal, meat and bone meal, skim milk, whey protein, distillers' by-products, barley, maize, oats, rye, rice, gluten meal, locust bean, canola, feather meal, sorghum, safflower seed, single cell protein, and yeast, all of which are suitable for feeding to ruminants to improve the quality of their protein intake. Such materials may be ground as necessary before inclusion in the new feedstuffs.

The lipid content of the newfeedstuffs is derived from the water-insoluble fatty acid salt and any lipid present in the protected nutritional material, and may vary within very wide limits. While it is possible to produce feedstuffs in accordance with the invention containing a low percentage of lipid, it is advantageous for the nutritional standpoint to produce a feedstuff containing about 50% lipid material up to about 90% so that the lipid content of the diet of the fed ruminents can be increased.

In the feedstuffs of the present invention the nutritional material is protected by the edible water -insoluble fatty acid salt or salts. At the level of acidity or pH range normally found in the rumen, the fatty acid salt is insoluble, but as the feedstuff passes to the relatively acidic conditions of the abomasum and small intestine, the salt is converted into the free acid which can then be digested, while the proteinaceous or other material previously coated and thus resistant to microbial breakdown in the rumen can bs digested in the normal way. The edible fatty acid salt itself is resistant to microbial breakdown or fermentation in the rumen.The physical coating of the proteinaceous or other material is achieved by both adsorption and absorption of the edible waterinsoluble fatty acid salt onto and into the surfaces of the proteinaceous or other material.

The fatty acid component may be derived from any edible fatty acid, for example stearic acid, lauric acid, myristic acid, palmitic acid, claim acid, linoleic acid or linolenic acid, or from a naturally occurring fat. If it is required to modify the fatty acid composition of the milk or of the depot Fat of the ruminant, for example by increasing the polyunsaturated content, then this can be done by using an acid oil or naturally occurring fat with a fatty acid composition corresponding to the fatty acid composition required in the milk or the depot fat.

However, in practice, it is generally most conve nientto use a naturally occurring mixture of fats or fatty acids derived from, for example, beef tallow, soya oil, palm oil, corn oil, rape seed oil or lard. Such materials are produced as by-products of oil refining. Beef tallow acid oil is particularly suitable for use in the present invention. Soya oil and rape seed oil acids are polyunsaturated. Alternatively naturally occurring fats may be saponified with sodium hydroxide or other suitable alkali.

The choice of the cation of the edible water-insoluble fatty acid salt is limited by the considerations that it must be edible and also water-insoluble.

Calcium fulfils both these conditions, and magnesium salts can also be used, but most other metallic cations either form water-soluble fatty acid salts, e.g.

sodium and potassium, or are poisonous, e.g. zinc or barium.

The respective proportions of the nutritional material to be protected and the protective coating in the feedstuffs of the invention can vary within wide limits, since the protective coating itself has nutritional value. Preferably, however, the protective coating forms about 50% of the feedstuff, but as little as 1% up to about 80% may be used.

The feedstuffs in accordance with the present invention may be made in two main ways, the choice of which is largely dictated by the nature of the product required, the preferred equipment and the preferred raw materials.

A first way of producing feedstuffs in accordance with the invention comprises forming a dispersion of the nutritional material to be protected in an aqueous solution of a water-soluble salt of the fatty acid and then adding an aqueous solution of a compound comprising an edible cation, which forms a water-insoluble salt with the fatty acid, so that the edible water-insoluble fatty acid salt is precipitated as a protective coating on the dispersed nutritional mate rial. To operate this process, the water-soluble salt of the fatty acid is first dissolved in water, conveniently by direct neutralisation of the fatty acid with an appropriate alkali such as sodium or potassium hydroxide or ammonia, or a solution of the fatty acid salt may be produced directly by saponification of a naturally occurring fat with sodium hydroxide or other suitable alkali.The nutritional material, e.g. the soya bean meal, is then dispersed in the aqueous solution. Such dispersion is not diffiuS tto accomplish, because the water-soluble fatty acid salt is surface-active. An aqueous solution of a compound which reacts with the fatty acid salt by double decomposition to form the water-insoluble salt is then added. When, as is preferred, the calcium salt of the fatty acid is to be formed, a water soluble calcium salt such as calcium chloride is conveniently used. The process may be operated at room temperature or above, and the reaction mixture stirred continuously to ensure good dispersion of the nutritional material.The calcium or other salt of the fatty acid is precipitated on the nutritional material and provides it with a protective coating capable of resisting bacterial action in the rumen. The precipitated protected feedstuff can be filtered off and dried and ground or peileted. A freeflowing product may be obtained, which can easily be incorporated into other animal feedstuffs. The aqueous mother liquor from this process may be evaporated to dryness and the product obtained, which has some nutritional value, may be incorporated in a salt lick or other animal foodstuff.

Alternatively a feedstuff in accordance with the present invention may be made by dispersing the feedstuff to be protected in the fatty acid salt, while the latter is in the molten state, and then allowing the mixture to cool. By this method, a solid block of the dispersed nutritional material in a matrix of the fatty acid salt is obtained. Such blocks have excellent resistance to weathering, and may be fed to ruminant animals in the open air with little riskthat the feedstuff will be washed away by rain or other surface water. Ruminants are, however, able to assimilate the feedstuff by licking the blocks, as with other licks provided for ruminants.In this process, the molten salt may be formed directly by the reaction of the fatty acid with a base such as calcium oxide at elevated temperature in the presence of a small amount of water sufficient to promote the reaction between the acid and the base. The fatty acids themselves and the cation of the base may be the same as with the other process. If a feedstuff block is not required, it is, of course, possible to grind up the blockto produce a powder similar to that obtained by the first process.

It is known from United States Patent No.

3,051,571 that edible water-insoluble fatty acid salts by themselves can be administered to animals in orderto increase their consumption of lipids.

However it is surprising that a protective coating of water insoluble fatty acid salt produced in accordance with the present invention is capable of protecting nutritional materials in the rumen while still leaving them assimilible in the intestinal tract.

Moreover, the feedstuffs of the present invention do not interfere with the normal fermentation processes which occur in the rumen.

It is, therefore, possible, by using the feedstuffs of the present invention, to administer to ruminants extra nutritional material which can by-pass the rumen and only become available to the ruminant in the intestinal tract.

The feedstuffs of the invention are especially suitable for pelletting as they form pellets easily in standard pelletting equipment. Moreover mixing them with ordinary feedstuffs facilitates pelleting of the latter as well as causing an improvement in its nutritional value.

Administration of lipid material protected in accordance with the present invention to cows has been shown to increase the total milk yield and the milk fat percentage as compared with milk produced by comparable cows to whom the lipid supplement was not given. Material according to the invention produced by the procedure described in Example 1 below was fed to lactating dairy cows. The response in milk yield and milkfat production is illustrated: MILK YIELD MlLKFAT% (Litres per day) Control 14.2 3.36 Treatment (1600 16.6 3.84 grams of supplement per day) (17% increase) (13.3% increase) Feed stuff materials protected in accordance with this invention can be fed either on their own or in a compounded feeding stuff.Theoretical energy metabolism calculations have suggested that a high yielding dairy cow should receive 16% of its total feed energy as fatty acid energy. A 500 kg cow producing 30 kg of milk per day may thus require approximately 1.0 kg of lipid material per day, or 2.0 kg of material produced by the method given in Example 1.

The following Examples describe how feedstuffs in accordance with the present invention can be made.

Example 1 Beef tallow acid oil (66 Ibs, 30 kg) and water (440 Ibs, 200 kg) were heated together in a kettle by injection of steam to 90 C. Sodium hydroxide (9 Ibs, 4 kg) dissolved in water (200 Ibs, 91 kg) was then added to the kettle to convert the acid oil into a water-soluble sodium soap. The soap completely dissolved after about 15 minutes. Defatted heat-treated soya meal (66 libs, 30 kg) was then added to this solution and the mixture was thoroughly stirred.

Calcium chloride (25 Ibs, 11.4 kg) dissolved in water (40 Ibs, 18.2 kg) was then added with stirring to the mixture in the kettle. The calcium soap is formed as an insoluble precipitate which encapsulates the soya meal. The precipitate was filtered through a vacuum filter and then dried.

The beef tallow acid oil may be replaced by other acid oils or other fatty acids such as those mentioned above.

Example 2 Beef tallow (50 Ibs, 22.7 kg) was melted and mixed with water (340 Ibs, 155 kg) and heated to 90"C.

Caustic soda (7 Ibs, 3.2 kg) was added and heating was continued at 90"C to saponify the fat. More water (100 Ibs, 45 kg) was then added. Defatted soya meal (50 Ibs, 22.7 kg) was added and the mixture stirred thoroughly. Calcium chloride (17 Ibs, 7.7 kg) dissolved in water (100 Ibs, 4.5 kg) was added to the mixture in the kettle. The calcium soap was formed as a precipitate which encapsulates the soya meal.

The product is filtered through a vacuum filter and dried.

Example 3 Soya acid oil (78 Ibs, 35.5 kg) was placed in a kettle and heated to 60 C. Water (12 Ibs, 5.5 kg) was then added and the mixture was heated to 90"C and stirred. With continued stirring, calcium oxide (10 Ibs, 4.5 kg) was added slowly. Stirring was continued and the temperature raised to 11 00C, when the calcium oxide began to react with the acid oil. When the reaction was complete, the rate of stirring was increased and soya meal (22 Ibs, 10 kg) was blended thoroughly into the mass. When the mixing was complete, the mixture was removed from the kettle and allowed to cool in moulds.

Claims (28)

1. Afeedstuffcomprising a nutritional material protected by dispersion in a protective coating of an edible, water-insoluble fatty acid salt.

2. A feedstuff according to claim 1 in which the nutritional material comprises a protein, carbohydrate, mineral, dietary supplement or vitamin.

3. A feedstuff according to claim 1 comprising 5G to 90% total lipid.

4. A feedstuff according to claim 1 or 3 in which the nutritional material is an animal or vegetable protein.

5. A feedstuff according to claim 1 or 3 in which the nutritional material comprises one or more of grass meal, lucerne meal, field beans, pea protein, coconut meal, cottonseed, groundnut, linseed, palm kernel, detoxified soya bean, defatted soya bean meal, sunflower seed, rape seed, fishmeal, meat and bone meal, skin milk, whey protein, distillers' by-products barley, maize, oats, rye, rice, gluten meal, locust bean, canola, feather meal, sorghum, safflower seed, single cell protein and yeast.

6. A feedstuff according to any of claims 1 to 5 in which the fatty acid salt comprises a salt of one or more of stearic acid, lauric acid, myristic acid, palmitic acid, oleic acid, linoleic acid or linolenic acid.

7. A feedstuff according to any of claims 1 to 5, in which the fatty acid salt comprises a salt of a mixture of fatty acids derived from beef tallow, soya oil, palm oil, corn oil, rape seed oil or lard.

8. A feedstuff according to any one of claims 1 to 7 in which the said salt is a calcium salt.

9. A feedstuff according to claim 1 substantially as described in any one of Examples 1 to 3.

10. A process for the production of a feedstuff as claimed in any one of claims 1 to 8 which comprises forming a dispersion of the nutritional material in an aqueous solution of a water soluble salt of the said fatty acid and then adding an aqueous solution of a compound comprising an edible cation which forms a water-insoluble salt with the said fatty acid, so that an edible water insoluble fatty acid salt is precipitated and forms a protective coating on the dispersed nutritional material.

11. Process according to claim lOin which the said water soluble salt is a sodium, potassium or ammonium salt.

12. Process according to claim 10 or 11 in which the said water soluble salt is formed in situ by reaction of an alkali with the fatty acid.

13. Process according to claim 10 or 11 in which the said water-soluble salt is formed in situ by saponification of a fat with an alkali.

14. Process according to any of claims 10 to 13 in which the compound comprising an edible cation is a water soluble calcium salt.

15. Process according to claim 14 in which the calcium salt is calcium chloride.

16. Process according to claim 10 substantially as described in Example 1 or 2.

17. Process for the production of a feedstuff as claimed in any one of claims 1 to 8 which comprises dispersing the nutritional material in the said fatty acid salt while the latter is in the molten state, and allowing the mixture to cool.

18. Process according to claim 17 in which the molten salt is formed by reaction of the fatty acid with a base containing an edible cation at elevated temperature in the presence of a small amount of water.

19. Process according to claim 18 in which the base is calcium oxide.

20. Process according to claim 17 substantially as described in Example 3.

21. Afeedstuff according to claim 1 when produced by the process of any of claims 10 to 20.

22. A pelleted feedstuff comprising a feedstuff as claimed in any of claims 1 to 9 or 21 by itself or compounded with another feedstuff.

23. A feedstuff as claimed in any of claims 1 to 9 or 21 in the form of a free flowing powder.

24. A feedstuff as claimed in any of claims 1 to 9 or 21 in the form of a block.

25. A feedstuff as claimed in any of claims 22 to 24 containing at least 50% lipid.

26. A feedstuff as claimed in any of claims 22 to 25 in which at least part of the lipid material is polyunsaturated.

27. A feedstuff as claimed in any of claims 22 to 26 in which the lipid material contained in the feedstuff is liquid prior to incorporation therein.

28. Method of feeding ruminant and other economically valuable animals which comprises sup plying said animals with a feedstuff as claimed in any one of claims 1 to 9 or 21 to 27.