JP6195546B2 - Fish feed without using fish meal and method for producing the same - Google Patents

Description

  The present invention relates to fish feed and a method for producing the same.

Conventionally, as a feed for fish farming, a solid feed obtained by blending an animal raw material and a vegetable raw material, and molding and processing the raw material into pellets has been widely used.
Such solid feed is made by mixing animal raw materials, vegetable raw materials (eg vegetable oil meal, cereals, potatoes, etc.) and feed additives, adding steam and water, heating, and pelletizing. Manufactured by molding.

  As an animal raw material, fish meal is mainly used because it is excellent in preservability and excellent in palatability and digestibility by fish and shellfish, and a high ratio of about 40 to 60% by mass in the solid feed. Is added.

  However, the production of fish meal requires a process of subjecting raw fish to heat treatment such as steaming, dehydrating and re-adding the concentrated extract, followed by heat drying and crushing, which requires a lot of labor and cost. . In addition, due to a decrease in the catch of sardine, which is a raw material for fish meal, the production of Japanese fish meal has decreased, and it has to depend on imported fish meal, which is subject to the import raw material price from overseas. For these reasons, there is a need for fish feed that reduces the amount of fish meal used (Patent Documents 1 and 2).

Feeds with reduced amounts of fish meal added have been studied, but there has been a decrease in growth due to poor feeding, and satisfactory results have not been obtained.
In addition, there is a method of adding various nutrients to supplement the nutrients of the reduced fish meal, but there is a problem that this increases the manufacturing cost and raw material cost.
In addition, as a technique for supplementing animal protein from raw materials other than fish meal, there is Oregon moist pellet obtained by mixing and granulating frozen fish and blended feed powder (Patent Document 3).

  However, since Oregon moist pellets are not heat-treated, they need to be fed immediately after granulation or stored frozen. In addition, after thawing, quality deterioration due to oxidation is quick, and storage stability is remarkably inferior. Further, the plant raw material in the mixed feed powder contains an absorption inhibitor such as trypsin inhibitor. This absorption inhibitory factor is deactivated by heat treatment, but in the Oregon moist pellet, it is not deactivated due to non-heating and inhibits digestion and absorption by fish. Therefore, there is a limit to the amount of plant raw material added to the Oregon moist pellets, generally 10% by mass (dry mass), and at most 25% by mass (total dry mass) of the feed. Dry mass) is the limit. In addition, Oregon moist pellets have the problem of melting into the water before the fish feed and causing marine pollution.

JP-A-11-98963 JP-A-8-89178 Japanese Patent Laid-Open No. 9-172882

  The present inventors have solved the above-mentioned problems, are fish feed that does not contain fish meal, have excellent palatability and digestibility by seafood, and can be stored at room temperature for a long period of time, It aims at providing the feed for fish farming manufactured at low cost, and its manufacturing method.

  As a result of various studies, the present inventor is a manufacturing method that does not require the heating / drying steps that are required before introducing animal raw materials into an extruder and that has been performed in the production of fish meal, etc. It has been found that the above-mentioned problems can be solved by heating the animal raw material and the powdery vegetable raw material simultaneously at the time of extrusion molding, and minimizing the heating process.

  That is, the present inventor made an animal raw material selected from fresh fish or fish processing residue into a paste, and obtained a mixture containing the obtained pasty raw material and a powdery raw material mainly composed of a vegetable raw material. It has been found that a method for producing fish feed characterized by kneading, heating, and extruding from a die, and a fish feed produced thereby achieve the above object.

The present invention is characterized by the following points.
1. An animal raw material selected from fresh fish or fish processing residue is made into a paste, and a mixture containing the obtained pasty raw material and a powdery raw material mainly composed of a vegetable raw material is kneaded with an extruder, heated, A method for producing a feed for fish farming, characterized by extruding from a die.
2. 2. The production method according to 1 above, wherein the fresh fish or fish processing residue is ground into a paste so as to be able to pass through a sieve having an aperture of ½ or less of an extruder die diameter.
3. 3. The production method according to 1 or 2 above, wherein the mixture contains the pasty raw material in a wet mass range of 5 to 40 mass%.
4). 4. The production method according to any one of the above items 1 to 3, wherein the pasty raw material has a water content of 30 to 90% by mass.
5. It is manufactured by the manufacturing method in any one of said 1-4, The feed for fish farming characterized by the above-mentioned.
6). The feed for fish farming according to 5 above, which does not contain animal raw materials other than the fresh fish, fish processing residue and fish oil.
7). Contains 47 to 99.5% by mass of vegetable material and 0.5 to 28% by mass of paste-like material on a dry mass basis (calculated assuming water content of 0%) with respect to the total mass of feed for fish farming The feed for fish farming as described in 5 or 6 above, wherein
8). The feed for fish farming according to any one of 5 to 7 above, wherein the water content is 5 to 15% by mass.

According to the production method of the present invention, it is possible to produce a feed for fish farming that shows high digestibility and absorbability and is excellent in preservability without taking much labor and cost for producing fish meal.
In particular, the present invention effectively uses domestic unused raw materials such as waste such as unused fish and fish processing residues that are caught and discarded domestically instead of fish meal. Therefore, it is not affected by the market price of imported fish meal.

  In addition, unlike unheated feed such as Oregon moist pellets, heating during the molding process not only provides excellent storage stability, but also prevents digestion and absorption inhibition due to inhibitors contained in plant raw materials, A highly nutritive feed can be provided by pregelatinizing starch. Therefore, it is possible to increase the blending ratio of the plant raw material in the feed, and to reduce the cost and increase the storage stability while maintaining good digestibility. Moreover, the absorption rate is high and the amount of feeding can be reduced. In addition, unlike Oregon moist pellets, an automatic feeder can be used.

  In addition, according to the production method of the present invention, fresh fish and fish processing residues to be added as animal raw materials may be pretreated by simply making a paste with a cutter or the like before being put into the extruder. Thus, it is not necessary to repeat heating and drying in advance.

Therefore, the time and cost required for production can be greatly reduced, and further, deterioration of the raw material quality caused by repeating the heating process can be minimized. That is, since the feed for fish farming of the present invention is produced by only one heating process, it exhibits high nutritional value and palatability.
Furthermore, the feed for fish farming of the present invention has a small amount of dissipation during feeding and a small burden on the fishery environment.

The present invention is described in detail below.
(1) Vegetable raw material and powdery raw material mainly composed of the vegetable raw material Examples of the vegetable raw material used in the present invention include cereals, potatoes, and vegetable oil meals.

Examples of cereals include potato starch, tapioca starch, corn starch, dextrin, cassava meal, wheat flour, barley, rye, milled rice, kinakome, corn, milo, bread crumbs and the like.
Examples of the potatoes include rice bran oil lees, wheat and corn distilers grain solubles, shochu, white sake lees, lysine fermented lees and the like.

Examples of vegetable oil meal include corn gluten meal, soybean oil meal, molted soybean oil meal, concentrated soybean protein, fermented molted soybean oil meal, rapeseed oil meal, sesame oil meal, wheat gluten, corn protein, potato protein and the like.
In the present invention, the above plant raw materials may be used alone or in combination of two or more.

  Plant raw materials are generally known to contain digestive enzyme inhibitors such as trypsin inhibitors, which inhibit feed absorption in the fish body. Therefore, it is necessary to reduce the content of plant raw materials in non-heated feed such as moist pellets. However, according to the present invention, since the plant raw material is heated at the time of extrusion, the digestive enzyme inhibitor loses the binding force with the digestive enzyme and does not cause the aforementioned absorption inhibition.

  Therefore, in this invention, plant raw materials are the range of 47-99.5 mass% converted into dry mass with respect to the total mass (dry mass) of feed, More preferably, the range of 65-85 mass% is preferable. And can be blended. If the blending amount of the plant raw material is less than 47% by mass, granulation becomes difficult, which is not preferable. Moreover, when more than 85 mass%, palatability is bad and it is unpreferable.

  If necessary, a powdery additive mainly for vegetable raw materials is added to the above-mentioned vegetable raw materials as appropriate in the range of 0 to 10% by mass, preferably 1 to 6% by mass, as usual. Used as a raw material.

  In the present invention, the powder form is a solid substance that can pass through a sieve having an aperture of 0.5 mm (30 mesh), and is defined as a powder form, a granular form, or a granular form. In addition, throughout the present specification, sieve openings and meshes are based on the provisions of JIS Z 8801. The particle size of the powder can be appropriately selected by those skilled in the art according to the size of the pellets as the final product.

  Examples of feed powder additives include nutritional ingredients such as vitamins, minerals, amino acids, sugars, ingredients such as coloring agents, flavorings, antioxidants, carboxymethylcellulose, sodium alginate, various gums, sodium polyacrylate, etc. However, depending on the type of fish to be fed, age, etc., those skilled in the art can appropriately select and mix them.

  Conventionally, animal protein raw materials containing various nutrients in a well-balanced manner are used by being appropriately mixed with powdered vegetable raw materials. In the present invention, fresh fish and / or fish processing residues are pasted. Since a sufficient amount of animal protein is supplemented by the pasty raw material, it is not necessary to add animal protein raw materials other than the pasty raw material. In particular, the present invention is characterized by not using fish meal.

(2) Animal raw materials Animal raw materials used in the present invention include fresh fish and fish processing residues. In the present invention, fresh fish and / or fish processing residues are put into an extruder together with the powdery raw material as a paste-like raw material, kneaded, heated, and extruded.

  Examples of the fresh fish include sardine, anchovy, mackerel, horse mackerel, saury, eel, eel, cod, squid, krill, and the like, but any available seafood can be used.

As the fish processing residue, various residues such as a head, a built-in body, a skin, a bone, a salmon, a scale, a tail, etc., which are by-produced during the processing of the above-described seafood can be used.
These fresh fish and fish processing residue are finely pulverized by an arbitrary pulverizing means, and further ground as necessary to obtain a paste-like raw material.

  As crushing means and grinding means, conventional choppers, silent cutters, micro cutters, mass colliders, refiners, etc. can be used as appropriate according to the desired degree of crushing or according to the type of fresh fish and fish processing residue used. Can be selected or omitted.

  Fresh fish and fish processing residue contain solids of various sizes such as bones, skins, and scales, so if they are put into an extruder without adjusting the pulverization degree of the paste, solids larger than the die diameter will form die holes. It fills up and granulation becomes unstable.

Even if the solid is smaller than the die diameter, clogging occurs when the solid enters the die hole at the same time. In order to prevent these troubles, the paste-like raw material is pulverized and / or ground to such an extent that it can pass through a sieve having an aperture of 1/2 or less, more preferably 1/3 or less of the extruder die diameter. It is preferable.
In order to obtain a desired degree of pulverization, the paste-like raw material may be passed through a sieve having a desired opening before being applied to the extruder.

  The pasty raw material may contain water in the range of 30 to 90% by mass with respect to the total mass. When the water content is less than 30% by mass, there is no fluidity, which is not preferable. Moreover, when more than 90 mass%, a palatability component is insufficient and is not preferable. If the water content is too low, it can be adjusted to the desired water content by adding water, and if it is too high, it can be dehydrated or dried.

  The pasty raw material is fed into an extruder or conditioner by a pump or the like, and a powdery raw material mainly composed of vegetable raw materials, and in some cases, a liquid additive such as oil or a liquid vitamin agent. , And mixed with steam and water added according to the manufacturing process.

  As the oil added here, any of vegetable oil and animal fat can be used. Fish oil, soybean oil, cottonseed oil and the like can be mentioned, and fish oil is particularly preferably used because of excellent food intake. As the fish oil, conventional fish oils including liver oil can be used, and preferred examples include sardine oil, saury oil, squid oil and the like.

  In the mixture of the pasty raw material made of the animal raw material, the powdery raw material mainly composed of vegetable raw material, and the additive such as oil added in some cases, the pasty raw material is based on the total mass of the mixture. In the range of 5 to 40% by weight, more preferably in the range of 10 to 30% by weight.

  If the blending amount of the pasty raw material is less than 5% by mass, the palatability substances are insufficient, and the digestive absorbability is inferior, which is not preferable. On the other hand, when the amount is more than 40% by mass, the handleability of the mixture is inferior and granulation becomes difficult.

  Moreover, a paste-form raw material is mix | blended in the range of 0.5-28 mass% in conversion to dry mass with respect to the total mass (dry mass) of feed, More preferably, it exists in the range of 5-28 mass%. be able to. When the amount of the pasty raw material is less than 0.5% by mass, the palatability substances are insufficient, and the digestive absorbability is inferior, which is not preferable. On the other hand, when the content is more than 28% by mass, the handleability of the mixture is inferior and granulation becomes difficult.

(3) Extrusion Molding The mixture consisting of the above powdery raw material, pasty raw material, oil, etc. is mixed, kneaded and heated by the rotation of the screw in the barrel (cylinder) of the extruder (extruder). While being conveyed in the die direction (exit direction).

  Here, it is preferable that a heating process is 60 degreeC or more and 60 second or more, More preferably, it is 90 to 110 degreeC for 40 to 60 second. If the heating temperature is lower than this, or if the heating time is shorter than this, the fish protein will not be denatured.

  In addition, absorption inhibitors (such as trypsin inhibitors) in plant raw materials are not sufficiently inactivated, and digestion and absorption by fish are inhibited. Moreover, the sterilization by heating becomes inadequate and storage stability is impaired. On the other hand, if the heating temperature is too high or the heating time is too long, nutritional value and palatability are impaired. The heating temperature and the heating time can be adjusted by the transport time to the heater or die incorporated in the barrel.

  The said mixture is conveyed to die | dye, Then, it is extruded from die | dye, is cut | disconnected to a pellet form, and the feed for fish farming of this invention is manufactured. A person skilled in the art can appropriately set the die diameter of the die plate and the numerical aperture of the die according to the use of the feed. A person skilled in the art can appropriately set the hardness of the feed, the sedimentation property to water, and the like by adjusting the opening area of the die plate and the feed rate of the raw material and adjusting the pressure during extrusion.

  The feed for fish farming of the present invention finally obtained is based on dry mass, the content of plant raw material is 47-99.5% by mass, the content of paste-like raw material is 0.5-28% by mass, Furthermore, the oil content is preferably 0 to 25% by mass.

Moreover, it is preferable that a moisture content is 5-15 mass% on a wet mass basis. You may prepare so that it may become a desired moisture content by making it dry after forming in a pellet form.
When the oil content is more than 25% by mass, molding becomes difficult, which is not preferable. Further, if the water content is less than 5% by mass, thermal denaturation can be caused. On the other hand, when it is more than 15% by mass, the room temperature storage stability is lowered.

The feed for fish farming of the present invention may be of any size depending on the type and size of the seafood to be fed.
EXAMPLES The present invention will be specifically described below with reference to examples, but these do not limit the present invention.

In the following examples, various contents were measured by the following methods.
[Measurement method of water content of pasty raw material]
Accurately weigh 5-7 g of the analytical sample into an aluminum weighing pan (weighed in advance and weighed accurately), dry at 105 ± 2 ° C for 5 hours, and release in a desiccator. After cooling, weigh accurately and calculate the amount of water in the sample.

[Measurement method of water content of fish feed]
Accurately weigh 2 to 5 g of the analytical sample into an aluminum weighing pan (weighed in advance and weighed accurately), dry at 135 ± 2 ° C for 2 hours, and release in a desiccator. After cooling, weigh accurately and calculate the amount of water in the sample.

[Measuring method of plant raw materials and animal raw materials (dry mass) of fish feed]
Accurately weigh 2 to 5 g of the analytical sample into an aluminum weighing pan (weighed in advance and weighed accurately), dry at 135 ± 2 ° C for 2 hours, and release in a desiccator. After cooling, weigh accurately and calculate the amount of water in the sample.

[Example 1]
Concentrated soy protein 8% by weight, soybean oil cake 28% by weight, corn gluten meal 23% by weight, starch / wheat flour 11% by weight, feed powder additive (vitamin / mineral) 12% by weight, and fish oil 18% by weight A base formulation was prepared.

  On the other hand, anchovy and eel as fresh fish and fish processing residue are pulverized with a silent cutter, then pulverized with a microcutter, and the paste obtained is passed through a sieve with an opening of 2.1 mm to give a paste. A raw material was prepared. The water content was 71.2% by mass.

  The above basic composition was charged into a biaxial extruder (Alphalyzer 100 manufactured by Suehiro EPM Co., Ltd.) at a flow rate of 69.2 kg / h. The pasty raw material was fed into a twin-screw extruder at a flow rate of 33.6 kg / h by a Mono pump.

  The basic composition and paste-like raw material are kneaded under the processing conditions of a barrel temperature of 130 ° C., a rotational speed of 280 rpm, a conveyance time from the inlet to the die (heating time) of 50 seconds, a die diameter of 8 mm, and a die hole number of 1, The mixture was heated and extruded into a rod shape, and the ratio of diameter to length was cut with a cutter at a ratio of 1: 1 to produce a float-fed feed for fish farming of the present invention.

In the obtained fish feed, the content of the plant raw material was 86.6% by mass in terms of dry mass, and the content of the paste-like raw material was 13.4% by mass in terms of dry mass. Moreover, it dried with the dryer so that a water content might be the range of 5-10 mass%.
The obtained fish feed showed good moldability and could be stored at room temperature for a long time.

[Example 2]
A pellet-shaped fish feed of the present invention was produced in the same manner as in Example 1 except that the barrel temperature was 80 ° C.
In the obtained fish feed, the content of the plant raw material was 86.6% by mass in terms of dry mass, and the content of the paste-like raw material was 13.4% by mass in terms of dry mass. Moreover, it dried with the drier so that the water content might be in the range of 5 to 10% by mass.

[Example 3]
A pellet-shaped fish feed of the present invention was produced in the same manner as in Example 1 except that the barrel temperature was 110 ° C.
In the obtained fish feed, the content of the plant raw material was 86.6% by mass in terms of dry mass, and the content of the paste-like raw material was 13.4% by mass in terms of dry mass. Moreover, it dried with the drier so that the water content might be in the range of 5 to 10% by mass.

[Example 4]
In the same manner as in Example 1, the fish feed according to the present invention was produced. However, the conditions were changed in the following points.
The flow rate of the basic formulation was 43.5 kg / h. The flow rate of the pasty raw material was 11.5 kg / h. Furthermore, at a barrel temperature of 130 ° C., the rotation speed was 300 rpm, and the conveyance time from the inlet to the die was 40 seconds.

  In the obtained fish feed, the content of the plant raw material was 92.2% by mass in terms of dry mass, and the content of the pasty raw material was 7.8% by mass in terms of dry mass. Moreover, it dried with the drier so that the water content might be in the range of 5 to 10% by mass.

[Example 5]
A fish feed according to the present invention was produced in the same manner as in Example 4 except that the barrel temperature was 90 ° C.
In the obtained fish feed, the content of the plant raw material was 92.2% by mass in terms of dry mass, and the content of the pasty raw material was 7.8% by mass in terms of dry mass. Moreover, it dried with the drier so that the water content might be in the range of 5 to 10% by mass.

[Example 6]
In the same manner as in Example 1, the fish feed according to the present invention was produced. However, the conditions were changed in the following points.
The flow rate of the basic formulation was 69.2 kg / h. The flow rate of the pasty raw material was 8.9 kg / h. Furthermore, the barrel temperature was 110 ° C. and the rotation speed was 300 rpm.

In the obtained feed for fish farming, the content of the plant raw material was 96% by mass in dry mass, and the content of the paste-like raw material was 4% by mass in dry mass. Moreover, it dried with the drier so that the water content might be in the range of 5 to 10% by mass.
The obtained feed for fish farming showed sufficient moldability and could be stored for a long time at room temperature.

[Example 7]
Breeding of yellowtail fish was carried out using the fish feed produced in Example 3.
The test conditions were that 30 juveniles (average weight 48 g) were reared in a 1 ton aquarium, and were reared in warm seawater 23 ° C. for 28 days and feeding days 28 days.
For the test feed, the fish meal area was set as a reference area for the test, and a total of 3 test areas were set: the invention area and the plant area.
Tables 2 and 3 show the composition and analysis values of the feed of each section. The breeding results are shown in Table 1 and Graph 1.

As a result of the test, growth was inferior in the plant group of the plant raw material alone, but in the invention group, the growth equivalent to the fish meal group could be confirmed by giving the feed based on the examples.
The daily feeding rate is defined as follows, and “others” in the composition indicates vitamin mixture, inorganic mixture, amino acid mixture, wheat flour, and starch.
Daily feeding rate = amount of food ÷ [(weight at the end + body weight at the start) ÷ 2 × number of breeding days] × 100

[Example 8]
The rearing test of the red sea bream fry was carried out using the fish rearing feed produced in Example 3.
The test was carried out by feeding 30 red sea bream (average weight 8.6 g) in a 0.5 ton aquarium and keeping them in warm seawater at 23 ° C. for 28 days and feeding days.
For the test feed, the fish meal area was set as a reference area for the test, and a total of 3 test areas, an invention area and a plant area, were set.
Tables 5 and 6 show the composition and analytical values of the feed of each section. The breeding results are shown in Table 4 and Graph 2.
As a result of the test, although growth was inferior in the plant group of the plant raw material alone (P <0.01), in the invention group, growth equivalent to the fish meal group could be confirmed by giving the feed based on the examples.

[Example 9]
Using the fish feed produced in Example 3, a breeding test was carried out for larvae.
The test conditions were as follows: 27 coho salmon (average body weight 6 g) were reared in an 80 L aquarium, and were reared in well water at 18 to 19 ° C. under conditions of 28 days of breeding and 24 days of feeding.
For the test feed, the fish meal area was set as a reference area for the test, and an invention area was set.
Tables 8 and 9 show the composition and analytical values of the feed of each section. The breeding results are shown in Table 7 and Graph 3.
The growth of the test feed was compared in the fish meal area. The breeding results are shown in Table 7 and Graph 3.
As a result of the test, the same amount of each feed was fed in the fish meal area and the invention area, and the final picked-up weight after breeding for 4 weeks was a difference of 0.4 g. However, the growth of freshwater fish was confirmed to be the same as that of the fish meal area.

As is clear from the above examples and the like, the fish feed of the present invention is a fish feed that does not contain fish meal, but has excellent palatability and digestibility by seafood, and can be stored at room temperature for a long time. It was confirmed that it can be manufactured at a low cost.

Claims (1)

An animal raw material selected from fresh fish or fish processing residue is made into a paste, and a mixture containing the obtained pasty raw material and a powdery raw material mainly composed of a vegetable raw material is kneaded with an extruder, heated, A method for producing fish feed that is extruded from a die,
The plant raw material is blended in a range of 65 to 85% by mass in terms of dry mass with respect to the total mass of the feed ,
The mixture includes a paste-like raw material in a range of 10 to 30% by mass of wet mass,
The water content of the pasty raw material is 30 to 90% by mass,
The fresh fish or fish processing residue is pasted into a paste so that it can pass through a sieve having an opening of 1/3 or less of the extruder die diameter.
The said heating is performed at 90-110 degreeC for 40 to 60 second so that the protein of the fish meat in a mixture may denature | denaturate and the absorption inhibitor in a plant raw material may be deactivated.