GB1568911A - Feed protein sources and their preparation - Google Patents

Description

(54) FEED PROTEIN SOURCES AND THEIR PREPARATION (71) We, TOYO JOZO KABUSHIKI KAISHA a Corporation organised under the laws of Japan of 632-1 Mifuku, Ohito-cho, Tagata-gun, Shizuoka-ken, Japan, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to concentrates obtained by ultrafiltration of aqueous extracts of fish meat and to dried products obtained therefrom, the concentrates and dried products being useful as sources of feed protein.

Methods of extracting water-soluble proteins from fish meat and water have been studied, but commercial methods have not yet been established on account of the cost involved in concentrating and drying a dilute extract by heating. In addition, by-product water formed when manufacturing fish meat powder from an extract of fish meat by heating has most of its proteins derived from collagen and is of low nutritive value.

We have found that concentrates obtained by ultrafiltration at a temperature below 60"C from an aqueous extract of fish meat and containing substances having weight average molecular weights of not less than 10,000 and dried products therefrom contain digestible water-soluble proteins which can be digested at rates similar to the rates at which milk proteins are dlgested. The concentrates have similar compositions of amino acids to the essential amino acids contents of milk protein. The net protein ratios determined in animal experiments are higher than those for milk protein, indicating the high nutritive values of the concentrates and their dried products which are accordingly suitable for use in or as foods, particularly health diets or artificial milks for infant animals.These products have remarkable utility not only economically, but nutritively and digestively for the body.

The invention thus provides also digestible protein foods and feedstuffs containing watersoluble protein concentrates or dried products thereof as effective ingredients, the concentrates having been obtained by ultrafiltration at a temperature below 60"C of an aqueous extract of fish meat, the concentrates containing substances having weight average molecular weights of not less than 10,000.

The aqueous extract of fish meat used in accordance with this invention can be prepared as follows: Whole bodies or slices of appropriate fishes or fish meat scraps are added to water and extraction is carried out for 5 to 30 minutes with stirring, then the extract is obtained after separation from the solids remaining. Water waste from the manufacture of ground fish meat can also be used as the aqueous extract. It is preferable to remove oil and fat from these solutions, for example by means of a centrifuge.The aqueous extract is heated to a temperature of 35-60"C, preferably 40-45"C, the pH of the extract solution is adjusted to 4.8 - 6.0 with an acid such as hydrochloric acid or acetic acid, preferably to 5.0 - 5.5, and then ultrafiltration is conducted to yield a concentrate of substances having weight average molecular weights of not less than 10,000.

The liquid concentrates thus obtained are of high viscosity and contain water-soluble proteins. They can be employed as such, i.e. in the form of concentrates, or in the form of dried products prepared by known means such as spray drying and lyophilization according to the desired form of foods or feeds.

The products of this invention can be employed as feeds for poultry, also as sources of protein in feeds for an extensive variety of mammals, such as livestock, pets such as dogs or cats, and monkeys and various experimental animals. Particularly in view of their excellent digestibility and high nutritive values these products are useful as sources of protein for use in artificial milk for infant animals or newly weaned animals.

In addition, in view of their excellent digestibility and high nutritive values the products of this invention can be added to bread, noodles, cakes, sausages, hamburgers and croquettes, as low-costsources of protein replacing powdered milk or its substitutes such as bean milk. The products of the invention can be used in pastes or sausages, and are particularly useful as sources of protein for baby foods, health diets for the aged and children, and diets for patients.

When manufacturing foods and feedstuffs of high nutritive values the products of the invention can be employed as the sole source of protein, or in combination with other sources of protein such as powdered skim milk, and further appropriately combined with other dietary substances, such as inorganic salts and various vitamins, in accordance with the prior known prescriptions. They can also be employed in the form of liquids, pellets or powder, for example by addition of an emulsifier, in compliance with the desired shape of the foods or feedstuffs.

Foods and foodstuffs can thus be composed of a concentrate or dried product obtained in accordance with this invention, either alone as a protein source or in combination with, for example, powdered skim milk or casein, energy sources such as powdered wheat gluten, alpha starch, glucose, purified lard or soy bean oil, inorganic salts such as table salt or calcium phosphate, various vitamins such as vitamins A, B, D and E and choline chloride, and emulsifiers such as fatty acid esters of glycerin.When preparing an artificial milk suitable for newly weaned pigs these components suitably are combined so that the crude fat content is about 5% by weight, the crude protein content is about 4% by weight, the carbohydrate content is about 5 by weight and the crude ash content is about 1 %by weight (a total of solid contents of about 15% by weight) with addition of water as required.

The digestibility and high nutritive values of product of the present invention have been investigated experimentally as follows: Experiment 1.

Determination of digestion rate and net protein ratio: 40 Male rats of the Wistar strain, 25-27 days old (4-5 days after weaning) were divided into 4 groups of 10 animals. To one of these groups (Control group) a proteinless feed was supplied and to the remaining 3 groups were fed semisynthetic feeds combined with (i) a product of the present invention (a powder obtained as in Example 1 below), (ii) vitamin-free casein, and (iii) fish meat powder (trade name: Hokuyo Meal) to make a crude protein content of 10% by weight in each case. The animals were kept in individual cages for 10 days, while the feeds were taken ad libitum.

i) Digestion rate: The digestion rates were determined on the feeds given on days 4-7 for 4 days.

Determination of the digestion rate was conducted by the method of total fecal collection and true digestion rate was calculated by determination of metabolic fecal nitrogen in the Control group given the feed containing no protein.

The results indicated a sham digestion rate for a product of the invention of 92.8 % and a true digestion rate of 97.7 % as seen from Table 1, showing almost similar values to those for a vitamin-free casein feed determined at the same time and greater values than those for a Hokuyo Meal feed.

Table 1.

Sham Digestion True Digestion Feed Rate Rate (i) Product of the 92.8 + 0.36% 97.7 + 0.33% present invention (ii) Vitamin-free casein 92.2 + 1.88% 97.1 + 1.88% (iii) Hokuyo Meal 90.7 + 0.83% 95.7 + 0.86% Intake N - Fecal N Sham Digestion Rate = Intake N x 100 Intake N-(Fecal N-Metabolic Fecal N) x 100 True Digestion Rate = Intake N Metabolic Fecal N (mg) = Feed Intake (g) X 0.95 (mg) Mean Fecal N (mg) in Group given Protein-less Feeds 0.95 (mg) = Feed Intake (g) ii) Net protein ratio: The net protein ratios were determined for 10 days. In accordance with the net protein ratio determination method of Benders the feed intakes and the weight gains of the animals were measured for each individual.

As shown in Table 2, the results revealed a net protein ratio as high as 4.76 for the group given the product of the present invention, while these values were respectively 3.79 and 4.23 for the groups given the vitamin-free casein and the Hokuyo Meal.

Table 2.

(i) (ii) (iii) Proteinless Product of Vitamin Hokuyo Group the present free Case- Meal Group (Control) invention ein Group Group Initial body weight 66.3#4.3g 66.1#5.8g 66.2#5.4g 65.2#4.9g Final body weight 53.3#2.9 111.6#8.7 85.3#5.7 95.5#9.1 Body weight gain -13.0#2.5 45.5#5.7 19.1#6.7 30.3#5.7 Feed intake 45.5#4.4 111.2#7.7 76.6#11.7 95.1#7.3 Intake of supplied protein - 12.29#0.85 8.48#1.29 10.20#0.79 Net protein ratio - 4.76#0.26 3.79#0.50 4.24#0.28 Feed intake of supplied protein = Dried feed intake X (crude protein content of dried supplied feed - crude protein content of protein-less feed) Body weight gain + Reduced weight of group N.P.R* = - given protein-less feed Intake Intake of supplied protein (g) * Net protein Ratio.

Experiment 2.

1) 16 Pigs of the Land Race strain were divided into 2 groups of 8 animals, on the day of weaning to homogenize roughly the source of mother pig, sex and body weight. One group was fed with a feed containing a product of the present invention (a powder obtained by the method of Example 1 below) and the other group was fed with a feed containing milk proteins (powdered skim milk + casein). The crude protein content of each feed was 22% by weight and each feed had a digestible energy content of 3,500 K cal/kg.

The animals were raised for 6 weeks and as a result of determination of the body weight gain during that time by each individual the mean body weight curves shown in Fig. 1 were obtained, from which it can be seen that the product of the present invention has almost similar nutritive value to that of milk proteins.

In addition, the feed conversion ratio of the group given the product of the present invention was 1.72 which was roughly similar to the ratio 1.76 for the group given in milk proteins.

2) 40 Newborn male broiler chickens were divided into 2 groups of 20 chickens. One group was fed with a feed containing a product of the present invention (a powder obtained by the method of Example 2 below) and the other group was fed with a feed containing casein as supplied protein. The crude protein content of each feed was 23 % by weight and each feed had a metabolic energy of 3,200 K cal/kg. The chickens were raised for 4 weeks and as a result of determination of the body weight gain during that time by each individual the mean body weight curves shown in Fig. 2 were obtained, which curves show that the product of the present invention has almost the same nutritive value as casein.

The feed conversion ratio [ = Feed Intake (g)/Body Weight gain (g)] of the group given the product of the present invention was 1.71, which was roughly similar to the ratio 1.79 for the group given casein.

The following Examples illustrate the present invention.

Example 1.

In manufacturing ground fish meat from Alaska pollacks the fish meat was separated with a screw press after the process of water-bleaching. Then 3,000 liters of the bleach waste were processed with a rotary screen (stainless steel net of 0.3 mm mesh) to remove minute meat flakes and the solution temperature was raised to 45 0C by warming with steam blows, and thereafter the pH was changed to 4.9 by addition of 1.5 liters of 10 N hydrochloric acid with thorough stirring. Into a 500 lit.-volume concentrating tank 350 liters of this solution were placed and ultrafiltration was conducted for 12 hours by adding the solution of raw material to make up for the reduced volume due to permeation, using an ultrafilter (Type UF 22S made by ABCOR, membrane size: 2 m2).Thus 340 liters of a concentrate and 2,645 liters of a permeate solution were obtained.

The concentrate was dried by spray drying and 23.58 kg of a dried powder (water content: 7.2%) was obtained.

Analysis of the dried powder gave the results set out in Table 3, indicating the high protein content and the low ash content of the powder. The proteinaceous substances in the concentrate had a weight average molecular weight of not less than 10,000. After hydrolysis of the powder the composition of amino acids was determined with the results shown in Table 4.

Table 4 also shows the amino acid compositions determined for Hokuyo Meal and powdered skim milk.

Table 3.

Component Content (% by weight) Water 7.2 Crude Protein 79.0 Pure Protein 73.2 Crude Fat 4.4 Crude Ash 5.0 Table 4.

Product of Hokoyo Skim Protein present invention meal milk Amino acid amino acid/ amino acid # amino acid amino acid 16gN 16gN 16gN Lysin@ 7.82 6.11 8.0 6.4 Histidine 2.40 1.87 2.0 2.7 Arginine 5.58 4.36 6.4 3.6 Tryptophan - 1.2* 1.2* Aspartic acid 11.15 8.71 10.3 Threonine 4.45 3.47 5.0 4.2 Serine 5.12 4.00 5.4 Glutanne acid 12.67 9.89 14 20.3 Pro@ne 3.59 2.80 4.8 Glycine 5.99 4.68 6.8 0.6 Aiamne 7.04 5.50 Cystine 0.62 0.49 Valine 5.54 4.33 5.1 6.6 Methlonine 3.24 2.53 3.2 2.4 Isoleucme 4.38 3.42 4.3 6.9 Leucme 8.95 6.99 8.2 9.9 Tyrosine 3.31 2.5@ 3.7 3.9 Phenylalanine 5.90 4.61 4.4 4.5 Nrecovery 91.2@ - 94.7% 92.5% *Tryptophan content was assayed.

Example 2 A feed composition was prepared by mixing the following ingredients homogeneously with a V-type mixer. The composition is suitable for use as a feed for young broiler chickens.

Ingredients Amount (% by weight) Product of the present invention 20 Yellow Corn 55.01 Milk 20 Alfalfa meal 3 Calcium carbonate 0.6 Calcium phosphate 0.6 Sodium chloride 0.45 Feed additive vitamins A, D & E 0.05 Feed additive vitamin B complex 0.1 Feed additive trace inorganic substances 0.1 Anti.coccidium agents 0.09 100 Example 3 A feed composition, suitable for use as an artificial milk for young pigs, was prepared by mixing the following ingredients using a V-type mixer:: Ingredients Amount (% by weight) Product of the present invention 35 a-starch 49 Glucose 10 60% powdered fat 3 Calcium carbonate 1.3 Calcium phosphate 1.0 Sodium chloride 0.4 Feed additive vitamin A & D 0.1 Feed additive vitamin B complex 0.1 Feed additive trace inorganic substances 0.1 Total 100 Example 4 The following ingredients were kneaded, after addition of an adequate amount of water, and the resulting mixture was roasted to prepare a biscuit-type dog food.

Ingredients Amount (% by weighty Product of the present invention 25 Roast corn 30.6 Roast wheat flour 30.0 Glucose 5 Purified lard 5 Sodium chloride 1.5 Calcium phosphate 1.5 Calcium carbonate 1.0 Feed additive vitamins A, D & E 0.1 Feed additive vitamin B complex 0.1 Feed additive trace vitamins 0.1 Feed additive trace inorganic substances 0.1 Total 100.

Example 5.

The following ingredients were kneaded, after addition of an adequate amount of water, the resulting mixture was molded, and biscuits for children were prepared by roasting.

Ingredients Amount S by weight) Product of the present invention 15 Wheat flour 54.6 Sugar 8 Condensed milk 10 Shortening oil 8 Starch syrup 2 Hen's egg 2 Sodium chloride 0.1 Swelling agent (sodium bicarbonate) 0.3 Total 100 WHAT WE CLAIM IS: 1. A source of feed protein suitable for use as a food or as a component of a foodstuff, the source comprising a concentrate containing proteinaceous substances having a weight average molecular weight of not less than 10,000, our a dried solid product thereof, the concentrate having been obtained by the ultrafiltration at a temperature below 60"C of an aqueous extract of fish meat.

2. A source according to claim 1 substantially as described with reference to Example 1.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (8)

**WARNING** start of CLMS field may overlap end of DESC **. Ingredients Amount (% by weighty Product of the present invention 25 Roast corn 30.6 Roast wheat flour 30.0 Glucose 5 Purified lard 5 Sodium chloride 1.5 Calcium phosphate 1.5 Calcium carbonate 1.0 Feed additive vitamins A, D & E 0.1 Feed additive vitamin B complex 0.1 Feed additive trace vitamins 0.1 Feed additive trace inorganic substances 0.1 Total 100. Example 5. The following ingredients were kneaded, after addition of an adequate amount of water, the resulting mixture was molded, and biscuits for children were prepared by roasting. Ingredients Amount S by weight) Product of the present invention 15 Wheat flour 54.6 Sugar 8 Condensed milk 10 Shortening oil 8 Starch syrup 2 Hen's egg 2 Sodium chloride 0.1 Swelling agent (sodium bicarbonate) 0.3 Total 100 WHAT WE CLAIM IS:

1. A source of feed protein suitable for use as a food or as a component of a foodstuff, the source comprising a concentrate containing proteinaceous substances having a weight average molecular weight of not less than 10,000, our a dried solid product thereof, the concentrate having been obtained by the ultrafiltration at a temperature below 60"C of an aqueous extract of fish meat.

2. A source according to claim 1 substantially as described with reference to Example 1.

3. A digestible protein food or feedstuff containing a concentrate or dried product

thereof as claimed in claim 1 or 2.

4. A food or feedstuff according to claim 3 substantially as described in any one of Examples 2 to 5.

5. A process for preparing a source of feed protein as claimed in claim 1 wherein an aqueous extract of fish meat is ultrafiltered at a temperature below 60"C, a concentrate fraction containing proteinaceous substances having a weight averate molecular weight of not less than 10,000 is recovered, and, if desired, the concentrate fraction is dried to provide a solid product.

6. A process according to claim 5 wherein the aqueous extract is acidified to a pH of 5 to 5.5 before ultrafiltration.

7. A process according to claim 5 or 6 wherein the aqueous extract is ultrafiltered at 40 to 45"C.

8. A process according to claim 5, 6 or 7 wherein oil and fat are removed from the aqueous extract before ultrafiltration.