JPS63123348A - Manufacturing method of block-shaped eel feed - Google Patents

Abstract

PURPOSE:To obtain the titled feed for eel, having improved shape-retainability, resistant to disintegration and dispersion in water, causing little feed loss and no water pollution, takable easily by eel and having improved feeding rate, by kneading a powdered mixture of raw materials for assorted feed for eel with water, forming the kneaded mixture in the form of a block and drying the product. CONSTITUTION:A powdered mixture of raw materials for assorted feed for eel is added with 15-20wt% wheat flour and kneaded in the presence of water (at an amount of preferably 10-15wt% of said mixture) preferably at high temperature and pressure. The kneaded mixture is formed in the form of a block and dried to obtain the objective feed.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing block feed suitable for eel farming.

In recent years, mixed feeds have come to be used as feed for eel farming, but most of them are powdered battered feeds because eels prefer soft foods, and they contain water, oil, and fat as raw materials for the powdered feed ingredients. They are fed by adding and kneading the mixture into a rice cake shape, which is then thrown into a feeding basket placed on the water surface.

However, since eel feeds actively, the feed tends to dissipate in the water, so a binder such as pregelatinized potato starch is used to give the feed strong cohesive properties, especially for whitebait and black eel. In order to mix the so-called feed for the fry stage by adding a large amount of water and making it soft, it is necessary to use a large amount of binder or use a special kneading machine.

However, with pasted feed using a binder, the binder is greatly affected by the properties of the feed compounding raw materials used and is often subject to aging. When feeding battered bait, the bait is dispersed into small pieces due to aging of the binder added to it, and about 10 to 15% of the bait is dissipated to the bottom of the water, wasting it and causing water pollution. . In addition, the above-mentioned battered bait also has the disadvantage that it requires a large amount of labor to knead powdered feed compounding ingredients with water and oil.

After that, in view of the drawbacks of battered feed, powdered feed ingredients were milled using a pellet mill to a particle size of 2 to 3 m/m.
A solid feed molded into pellets of about 100% was proposed. However, since this pellet solid feed is simply made by pressing the powdered raw material with a pellet mill to solidify it, it tends to settle in water and absorb water and disintegrate, leading to feed loss and deterioration of water quality. In addition, the feeding rate of eels is poor, which causes poor growth of eels.

Furthermore, recently, as a means to solve the drawbacks of these feeds,
So-called foaming floating baits in which the feed maintains floating properties have been proposed (for example, Japanese Patent Application Laid-Open No. 1983-91 No. 93).

In other words, this floating bait has a porous form made by molding feed ingredients using an expanding extruder type molding machine to a particle size of about 2.5 to 5 m/m, and is suitable for feeding. They can be fed by making a frame in the feeding area and scattering them as is. However, eels are not good at eating floating food, and it takes quite a few days to get used to it. Otherwise, the eel will repeatedly spit out the food even after putting it in its mouth and will not swallow the food, so it is necessary to adjust the particle size to suit the eel's mouth. However, in general eel farming ponds where large and small eels are mixed together, adjusting the particle size to suit the mouth of each eel as described above is not only troublesome, but also impractical in terms of manufacturing costs. Have difficulty. Therefore, with the above-mentioned floating bait, there is a problem in that only some of the eels are fed, while others are not fed enough, resulting in poor growth.

The present invention was developed in consideration of the problem of ridges in eel farming feed, and it is easy for eels to feed, and the feed disintegrates and dissipates in the water. An object of the present invention is to provide a method for producing block-shaped eel feed with good shape retention without causing any damage.

The present invention will be explained in detail below.

Structure of the present invention The feature of the present invention is that the powdered mixture of raw materials for eel feed is added with water and kneaded, then molded into a block and dried, or the powdered mixture of the above raw materials is added with water. The purpose is to produce block-shaped eel feed by kneading the mixture under heating and pressure, extruding it through a die, and cutting it into blocks.

In order to reduce the amount of eel, the present invention mixes each powder of raw materials for eel feed, or
Alternatively, a powdered mixture obtained by mixing and pulverizing the compounded feed is mixed with approximately 10 to 15% by weight of water and kneaded well, and then formed into a block shape, in which case the above-mentioned compounded raw materials are mixed. It is desirable that wheat flour, which is commonly used as a feed raw material, is added to the powdered mixture in an amount of usually 10 to 30% by weight, preferably 15 to 25% by weight, based on the compounded feed. This flour becomes caking as a result of kneading the above-mentioned powdered mixture, and in particular, the flour is gelatinized during kneading under heat and pressure. It is believed that the block obtained by molding forms a structure that has good shape retention even when it absorbs water, since it is molded by enclosing raw materials such as fish meal. Therefore, in the present invention, it is important to knead the powdered mixture of the blended raw materials, and it is particularly desirable to perform the kneading under heat and pressure.

The feed compounding raw materials used in the present invention may be those that are generally used as compounded feeds for eels, such as fish meal and wheat flour as the main ingredients, to which feed yeast, vitamins, and minerals are added.

In the present invention, when the powdered mixture as a raw material is directly added with water, kneaded, and molded into a block shape, the width is 2
00n+/m, length 300m/m and thickness 100m
After molding into a block shape of about /m2 and drying it by ventilation drying, freeze drying, etc. to a moisture content of around 5%, feed oil such as Kura Liver Oil is uniformly divided to about 5 to 8% on the outside. Spray it on the water and use it for feeding.

In addition, when adding water to the powdered mixture, kneading it under heat and pressure, and extruding it from a die to form a block, feed the powdered mixture into an extruder, and add 10 to 15 weight of water to it. % addition, cylinder internal temperature 100
~140℃, screw pressure 30~120 kg
The mixture is kneaded under heat and pressure of /cj, then extruded from a die into a strip, cut into lengths of about 100 m/m with a cutter, and dried. After drying, feed oil such as cod liver oil with antioxidants added thereto is evenly sprayed to a ratio of about 8% and used for feeding. .

In order to feed the block-shaped feed obtained as described above, it may be administered directly into water, or may be administered into a feeding cage placed above the water surface.

Hikari Plate ■ Since then, when the block-shaped feed obtained by the present invention is administered into water, it absorbs water from the part that comes in contact with water and becomes softened, making it easier for eels to eat as they bite into the softened part and tear it off. Furthermore, since the softened portion is soft enough to suit the palatability of the eel, it has the advantage of improving the feeding rate. Furthermore, this block-shaped feed has good shape retention, so it is difficult to disintegrate in water.
Therefore, there are no problems of feed loss or water pollution as with conventional solid feed.

EXAMPLES The present invention and its effects will be specifically explained below with reference to Examples.

Example 1 70 parts by weight of fish meal, 20 parts by weight of wheat flour, 5 parts by weight of feed yeast, 5 parts by weight of vitamins, minerals, etc., and the above-mentioned raw materials were mixed in a mixer, then crushed in a crusher, and then transferred to the hopper of an extruder. I invested in it. The temperature inside the cylinder is about 120℃, water is added 10-15%, and the pressure of about 70kg/cd is extruded from the die into a strip of width 50M/M x thickness 10M/H with a cutter.
After drying, feed oil added with antioxidants (preferably cod liver oil) is uniformly sprayed with a sprayer so that the external ratio is about 8%, and block feed for raised eel fry is prepared. I got it.

Example 2 65 parts by weight of fish meal, 20 parts by weight of wheat flour, 5 parts by weight of binder,
After pulverizing 5 parts by weight of vitamins, minerals, and other raw materials, use a pulverizer to crush them, add water in a mixer, knead them well, and form them into blocks of width 200M/M x length 300-μ x thickness 100M/M. After molding and drying this by freeze-drying to a moisture content of around 5%, feed oil (preferably cod liver oil) is uniformly sprayed with a sprayer so that the moisture content is 5%.
Obtained block feed.

Example 3 This example shows the results of an aquaculture test on glass eels fed with the block feed for cultivated eel fry obtained in Example 1. For comparison, a similar test was also conducted on a commercially available powdered glass eel compound feed. The result is the first
As shown in the table.

Table 1: 14mm) Average weight at the start of N-coupled pillar feeding 0.20G 0.20G
Average weight after 20 days 0.41G 0.50
Average weight after 40 days: 0.76G 1.1
0G Example 4 This example shows the results of a test in which eels were cultured for 30 days using the block feed obtained in Example 2, commercially available powdered feed, and floating bait. The aquaculture pond used 30 tsubo of heated circulating oil, and the water temperature was adjusted to 25-28°C.

In addition, the same feed oil as in Example 2 was added to the commercially available powdered feed in an amount of 5%.

The results are shown in Table 2.

Claims (4)

[Claims] (1) A method for producing a block-shaped eel feed, which comprises adding water to a powdered mixture of ingredients for eel feed, kneading it, forming it into a block shape, and drying it. (2) The production method according to claim (1), wherein the raw material for feed contains 10 to 30% by weight of wheat flour. (3) A method for producing a block-shaped eel feed, which comprises adding water to a powdered mixture of raw materials for eel feed, kneading it under heat and pressure, extruding it through a die, and cutting it into blocks. (4) The production method according to claim (3), wherein the raw material for feed contains 10 to 30% by weight of wheat flour.