JPH0561898B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for producing fish feed for marine aquaculture. More specifically, the present invention relates to a method for producing feed for fish farming and fish gathering that prevents ocean pollution caused by fish feed, and is floating and has a high rate of fish feeding. (Conventional technology and its problems) In recent years, fishing grounds in Japan have been significantly narrowed due to the dawn of the 200 nautical mile era. For this reason, aquaculture fishing is steadily growing. In particular, sea-feeding aquaculture, centered on yellowtail aquaculture, has shown remarkable progress, and has also expanded to include red sea bream, flounder, horse mackerel, puffer fish, prawns, and prawns.
Aquaculture of coho salmon and other species has begun, and the number of fish species targeted for marine culture is rapidly increasing. However, currently, the feed in marine aquaculture is fed fresh and frozen fish such as sardines and mackerel, which are often caught fish, in the form of minced, cut, or rounded fish, which causes water-soluble nutrients to be leached into the seawater. There is a problem that the predation rate of fish is low because there are many particles and they are scattered in seawater. For this reason,
Recently, fish feed (hereinafter referred to as moist pellets) is made by mixing and stirring fishmeal, oil cake, vitamins, minerals, and other fish feed ingredients with a binder, and then kneading the mixture with crushed raw feed to form granules. ) is rapidly becoming popular. Moist pellets are granulated using a binder, so when feeding them in seawater, they can prevent the bait from dissipating, and are floating, increasing the predation rate of fish, and preventing the elution of water-soluble nutrients. It is effective in preventing self-contamination. In addition, moist pellets are a nutritionally calculated scientific feed that combines nutrients such as vitamins and minerals with fish meal and oil cake, and it is also possible to uniformly mix therapeutic drugs. Until now, the use of water-soluble polymers such as carboxymethylcellulose alkali metal salts (usually sodium carboxymethylcellulose) and sodium alginate as a binder for moist pellets has been reported in Japanese Patent Publication No. 13773/1973. It is described in.
However, since general carboxymethyl cellulose alkali metal salts have a degree of substitution of carboxymethyl groups per anhydroglucose unit of 0.50 to 0.70, they have a problem of poor salt resistance and chemical resistance. If moist pellets are kneaded and granulated on board the ship and then fed as is, seawater is always used when crushing raw fish or thawing frozen fish. In this case, general CMC has poor salt tolerance, so its viscosity decreases and its cohesive force is weak, resulting in a lack of cohesive force when granulating moist pellets, and when administered to seawater, it tends to break apart and cause the bait to dissipate. Fish feed causes significant marine pollution, which is undesirable. Furthermore, a method for producing fish feed using an aqueous sodium alginate solution and calcium salt as main ingredients is described in Japanese Patent Publication No. 46350/1983. However, since sodium alginate is a natural product, there is a problem that the quality is unstable because the ingredients are not constant depending on the production area and year. (Means for Solving the Problems) As a result of intensive studies to improve these problems, the present inventor found that the degree of carboxymethyl group substitution per anhydroglucose unit in fish feed raw materials is 0.70 to 0.70.
1.50, water content is 5.0% by weight or less, and the viscosity of a 1% by weight aqueous solution is 2000 cps or more and 9000 cps or less at 25°C.
When a mixture obtained by blending CMC (abbreviated as CMC) as a binder is kneaded, molded, and granulated, it exhibits extremely good extrusion workability, and the resulting moist pellets have high caking power and moderate strength. It lasts long, is non-sticky, leaves beautiful skin, and has excellent shape retention. Furthermore, as a result of feeding moist pellets using the binder of the present invention in seawater, we found that there was no leaching of water-soluble nutrients into seawater, and the pellets had excellent floatability, resulting in a high predation rate for fish and less ocean pollution. The present invention has now been completed. That is, the present invention uses a feed material for fish farming as a binder, which has a carboxymethyl group substitution degree (hereinafter abbreviated as DS) per anhydroglucose unit of 0.70 to 1.50, has a moisture content of 5.0% by weight or less, and is a 1% by weight aqueous solution. Viscosity is 25
The present invention relates to a method for producing fish feed, which comprises kneading and granulating a mixture obtained by blending CMC of 2000 cps or more and 9000 cps or less at °C. Here, the fish feed raw materials include fish meal, oil cake, vitamins, minerals, and other powder feed raw materials for cultured fish, and crushed live feed such as raw fish and frozen fish. In addition, the DS is 0.70 to 1.50, the water content is 5.0% by weight or less, and the viscosity of a 1% by weight aqueous solution is 2000 cps at 25℃.
Above, CMC of 9000 cps or less is used as a binder. If the DS is less than 0.70, the salt resistance of CMC will be poor, and when seawater is used, the viscosity of CMC will decrease and the caking force will deteriorate. Furthermore, if the DS exceeds 1.50, it is difficult to produce CMC, and if the production is forced, the addition rate of monochloroacetic acid will decrease and the cost will increase. If the water content exceeds 5.0%, the water absorption of CMC deteriorates and the moist pellets become sticky and the pellets fuse together after granulation, making it difficult to feed. Furthermore, if the viscosity of the 1% aqueous solution is less than 2000 cps at 25°C, the cohesive strength will be poor.
Since the moist pellets are sticky and soft, the pellets fuse together after granulation, causing problems in feeding operations. Fish meal in the present invention is used as an animal protein source in fish feed, and includes white fish meal, brown fish meal, meat meal, meat and bone meal, feather meal, blood meal, skim milk powder, Antarctic krill meal, and squid meal. In addition, oil cake is commonly used as a vegetable raw material in fish feed, including grains, rice bran, soybeans and soybean meal,
These include starches, gluten meal, and Ruthen meal. Furthermore, vitamins include vitamin B ₁ , B ₂ ,
B ₆ , B ₁₂ , C, niacin, calcium pantothenate, choline chloride, folic acid, piotin, inositol, para-aminobenzoic acid, etc. are appropriately blended. Minerals such as phosphorus, calcium, magnesium, potassium, and sodium are mixed in consideration of the mineral content in the fish meal, which is the main raw material. In the present invention, when kneading and molding the crushed raw feed and the powdered feed, the mixing ratio is 80 to 30% by weight for the former and 20 to 30% by weight for the latter, depending on the feeding situation of the cultured fish.
The ratio is 70% by weight, preferably 50% by weight for both.
It is. Further, as a binder, the CMC of the present invention is blended in a powdered feed in an amount of 0.5 to 10% by weight, preferably 2 to 4% by weight. Furthermore, the present invention can be used as a binder.
It is also possible to use CMC in combination with water-soluble polymers that can be used for fish feed, such as sodium alginate, guar gum, hydroxyethylcellulose, methylcellulose, carboxymethylhydroxyethylcellulose, and hydroxypropylcellulose. In addition, the method of granulating moist pellets using CMC of the present invention as a binder is first applied to fishmeal, oil cake, vitamins, minerals, and other fish feed raw materials commonly used in fish feed. invention
After adding CMC and thoroughly mixing and stirring with a mixer to make a powdered feed, raw fish and frozen fish are crushed with a crusher, kneaded with the minced raw feed crushed material with a kneader, and granulated with a granulator. to get Moist Pellet. Examples of the present invention and comparative examples will be described below. (Example) Parts and % in the examples mean weight basis. Example 1 39 parts of 65% white fat meal, 5 parts of soybean meal
₁ part of vitamin B and 2 parts of a mixture of other vitamins, 2 parts of a mixture of calcium, phosphorus and other minerals, DS of 0.75 as a binder, water content of 4.2%, and the viscosity of a 1% aqueous solution is 3400 cps at 25°C. of
Pour 2 parts of CMC into a powder mixer and mix uniformly.
A powdered feed was obtained. Next, the raw fish sardines were cut and crushed using a crusher to obtain crushed raw bait sardines. Furthermore, 50 parts of crushed raw sardines and 50 parts of powdered feed were put into a kneader and kneaded uniformly, and then granulated with a granulator to reduce the diameter.
Moist pellets of 9.6 mm were obtained. The moist pellets obtained by granulation were free from stickiness and had beautiful skin. Next, the obtained moist pellets were administered into seawater to feed yellowtail, but the moist pellets were not fused to each other and the feeding workability was good. Furthermore, there was no elution into seawater, and the fish predation rate was good. Examples 2 to 5 Moist pellets were kneaded and molded using the CMC shown in Table 1 as a binder in the same manner as in Example 1. As a result, good moist pellets were obtained in all cases. Comparative Example 1 DS was used as a binder in the same manner as in Example 1.
0.61, water content is 8.8%, viscosity of 1% aqueous solution is 1250cps
As a result of kneading and molding moist pellets using CMC, the resulting moist pellets were extremely sticky and had poor texture. Furthermore, when the ground raw feed and the powdered feed were uniformly kneaded in a kneader, the mixture became lumpy and had poor extrusion workability. Further, the obtained moist pellets were administered into seawater to feed yellowtail, but the moist pellets fused together, making feeding difficult, resulting in poor feeding workability. Comparative Examples 2 to 4 Moist pellets were kneaded and molded using the CMC shown in Table 1 as a binder in the same manner as in Example 1, and the evaluation results were poor in all cases. 【table】

Claims (1)

[Claims] 1. The degree of carboxymethyl group substitution per anhydroglucose unit in the feed raw material for fish farming is 0.70 to 1.50,
The water content is 5.0% by weight or less, and the viscosity of a 1% by weight aqueous solution is
A method for producing fish feed, which comprises kneading and granulating a mixture obtained by blending carboxymethylcellulose alkali metal salts as a binder at 2000 cps or more and 9000 cps or less at 25°C.