IE64733B1

IE64733B1 - Cheese making

Info

Publication number: IE64733B1
Application number: IE361590A
Authority: IE
Inventors: Jean-Claude Robert
Original assignee: Rhone Poulenc Nutrition Animal
Priority date: 1989-10-10
Filing date: 1990-10-09
Publication date: 1995-09-06
Also published as: ZA908074B; DK0423000T3; KR0131871B1; AU638059B2; NZ235600A; JPH03139247A; ES2062453T3; AU6386490A; EP0423000B1; FR2652721B1; ATE99882T1; IE903615A1; IL95877A0; FR2652721A1; IL95877A; EP0423000A1; CA2027181A1; DE69005973D1; KR910007434A; DE69005973T2

Abstract

The present invention relates to the use, in cheese-making, of milk from animals having received a feed supplemented with amino acids in protected form.

Description

The present invention relates to the use, in the preparation of cheese, of milk from cows which have * received feed supplemented with protected amino acids.

It is known to supplement the feed of cows by . * adding to their basic food a supplement based on essential amino acids, which are principally lysine and methionine.

These essential amino acids, also known as limiting amino acids, are not synthesized in sufficient quantity by the cow from its daily food. The fermentation of foodstuffs in the rumen by digestive enzymes causes the formation of proteins known as microbial because they result from the action of microbes situated in the rumen. These proteins, as well as those which have passed through the rumen, are digested in the intestine of ruminants and provide the necessary amino acids in the quality and quantity necessary for the maintenance of the ruminants and the production of milk. During lactation, the mammary gland absorbs the greatest part (80 to 90%) of the natural resources of amino acids, and requires a supplement of limiting amino acids.

Increasing milk production by adding, to the conventional feed of ruminants, supplements based on tanned proteins or protected amino acids has been tried.

This addition of protected amino acids, optionally of lysine and/or of methionine, produces an increase in the .... level of proteins in cows1 milk. t It has now been discovered, surprisingly, that the - 2 milk from cows which have received a supplement of protected amino acids, preferably lysine and/or methionine, has completely unexpected cheese-making capabilities.

Such milk shows an appreciable increase in yield.of the quantity of curd produced per litre of milk compared with a cow which has received no supplement. In addition the cheese has increased solidity.

The feeding of protected amino acids can be carried out using amino acids protected by a polymer which is resistant to the pH conditions of the rumen and which is liberated in the abomasum and/or the intestine.

Suitable polymers include mixtures of basic amino copolymers with a hydrophobic substance the melting point of which is greater than 60’C and/or a copolymer insoluble in water.

The basic amino copolymer is preferably a copolymer based on styrene and vinylpyridine.

The hydrophobic substance having a melting point greater than 60*C is preferably stearic acid.

The copolymer insoluble in water is preferably ethylcellulose.

The amino acid can also be protected using a zeinbased copolymer and a hydrophobic substance the melting point of which is greater than 60 *C and/or a copolymer insoluble in water. The preferred hydrophobic substance and the preferred copolymer insoluble in water are the same as those described above.

All these protected amino acids are described for example in European Patent 188953, French Patents 2401621 and 2514261, European Patent 260186 and French Patents * 2606597 and 2582909.

They are included in the daily food of the cows at a rate of from 0 to 30 g of methionine and/or 0 to 100 g of lysine per day, the minimum figure for the sum of the two amino acids being at least 5 g per day.

The invention is illustrated in the following Example.

EXAMPLE The experimental animals were heifers of 8 to 12 weeks' lactation, the milk production level of which was from 22.5 to 30.5 kg per day.

The basic diet consisted of maize silage ad libitum. It was complemented by an energy-containing concentrate, a nitrogen-containing concentrate (gluten meal) and/or by a protected amino acids concentrate (treatment) or a control concentrate (neither amino acids nor protective product). The concentrates were fed in quantities which were identical for all the heifers and constant throughout the experiment (20 g of methionine base and 48 g of lysine base per day).

These amino acids were fed in the form of a mixture of coated methionine and of coated methionine/ lysine granules having the following compositions: Methionine/lysine granules: g of nucleus containing . 59.5% lysine.HCl . 14.5% methionine I . 12% talc . 14% binder (95% stearic acid, 5% 2-vinylpyridylstyrene copolymer (65/35)) g of coating containing . 30% 2-vinylpyridylstyrene 65/35 . 10% stearic acid . 60% talc Methionine granules containing: g of nucleus containing . 77.5% methionine . 10% talc . 12.5% binder containing 95% stearic acid and 5% 2-vinylpyridy1styrene copolymer (65/35) g of coating containing . 30% 2-vinylpyridylstyrene 65/35 . 10% stearic acid . 60% talc.

The experiment lasted 16 weeks and was divided into 4 periods of 4 weeks.

Determination of the chemical and technological properties of the milks On Tuesday of the last week of each period, samples of about 1 litre per cow were taken at the ( morning milking. A mean sample (500 ml per cow) was made up in each period for the 4 cows receiving the same treatment. Sodium penicillin G (200 IU per litre) was added to this milk, which was skimmed for technological tests.

The technological parameters were measured on the skimmed milk during its coagulation at 35°C by the action of rennet (5.2 mg of chymosin per litre) used at a rate of 0.13 mg of chymosin per litre of milk. These measurements were carried out on milk the pH of which was standardized at 6.6 (by the addition of lactic acid) and the mineral balance of which had been reestablished.

The readiness to coagulate is measured using a Formagraph (Foss Electric) and is represented by the incubation time, the time to firming and the consistency of the curd 30 minutes after the addition of rennet. It was measured on milk at the initial pH and at the standardized pH.

The fresh, dry and nitrogen cheese yields are determined one hour after adding rennet, by running of the whey, immediately followed by centrifugation.

THE EFFECT OF LYSINE/METHIONINE SUPPLEMENTS ON THE CHEESE-MAKING POTENTIAL OF MILK WITHOUT AMINO ACIDS WITH AMINO ACIDS Cheese yields (%) . fresh 18.4 19.3 . nitrogen 78.2 79.1 10 . dry matter 43.7 44.6 FORMAGRAPH - at initial pH . incubation time (min) 15.0 15.5 15 . time to firming (min) 6.8 6.8 . firmness of the curd (mm) 37.5 37.7 . coagulation speed: 2.3 2.3 incubation time/time to firming 20 - at standardized pH . incubation time (min) 13.8 14.5 . time to firming (min) 6.1 6.3 . firmness of the curd (mm) 39.3 40.1 . coagulation speed: 2.3 2.3 25 incubation time/time to firming THE EFFECT OF LYSINE/METHIONINE SUPPLEMENT + NATURE OF THE NITROGEN (MAIZE GLUTEN COMPLEMENT CONTAINING 60% PROTEIN) ON THE CHEESE-MAKING Ϊ POTENTIAL OF MILK WITHOUT AMINO ACIDS WITH AMINO ACIDS Cheese yields (%) 10 . fresh 17.9 19 . nitrogen 77.8 79 . dry matter 42.6 45.1 FORMAGRAPH 15 - at initial pH . incubation time (min) 15.3 14.8 . time to firming (min) 7.1 6.8 . firmness of the curd (mm) 36.4 38.2 - at standardized pH 20 . incubation time (min) 13.8 14.4 . time to firming (min) 6.4 6.6 . firmness of the curd (mm) 38.7 39.2 CLAIMS

Claims

1. A method of making cheese in which the milk comes from a cow which has received a feed supplemented by 4 an amino acid in a protected form.

2. A method according to claim 1 in which the amino acid is lysine and/or methionine.

3. A method according to claim 1 or 2 in which the amino acid is protected by a polymer which is resistant to the pH condition of the rumen and is liberated in the abomasum and/or the intestine of the cow.

4. A method according to claim 3 in which the amino acid is protected by a layer comprising a basic amino copolymer and a hydrophobic substance the melting point of which substance is greater than 60 ”C and/or a copolymer insoluble in water.

5. A method according to claim 3 in which the amino acid is protected by a layer comprising a zein-based copolymer and a hydrophobic substance the melting point of which substance is greater than 60*C and/or a copolymer insoluble in water.

6. A method according to claim 4 in which the amino acid is protected by a layer comprising a styrene vinylpyridine copolymer in association with a hydrophobic * substance which is stearic acid and a copolymer insoluble in water which is ethylcellulose.

7. A method according to any one of the preceding claims in which the supplementary feed comprises ; V | 0 to 30 g of methionine and 0 to 100 g of lysine/day in the r protected form, the minimum figure for the sum of the two amino acids being at least 5 g/day.

8. A method according to claim 1 substantially as hereinbefore described.

9. Cheese made by a method according to any one of claims 1 to 8.

10. The use in cheese making of milk from a cow which has received a feed supplemented by an amino acid in a protected form.