CN105746446B - A kind of decladding method of artemia eggs - Google Patents

Abstract

The invention provides a method for shelling Artemia eggs, which comprises the following steps: (1) Soaking commercial Artemia eggs in fresh water to make the eggs fully absorb water and swell. (2) Separate Artemia eggs, put them in the shelling solution containing trypsin, and stir slowly. (3) When the color of the eggs is observed to gradually change from brown to orange-red, add the terminator. (4) After inflating and stirring, let it stand still, separate the shelled eggs, rinse them with sea water, and then use them for hatching or direct feeding. The invention belongs to biological shelling, the raw materials used are all natural products, there is no chemical pollution to shelled eggs, no adverse effect on direct feeding or subsequent hatching, and the effect is stable.

Description

A kind of shelling method of Artemia eggs

technical field

The invention belongs to the technical field of artemia eggs application, and in particular relates to a shelling method for artemia eggs.

Background technique

Artemia, also known as Artemia, is a small crustacean distributed worldwide and lives in high-saline waters such as salt lakes and salt pans. Artemia eggs are high-quality aquatic nursery bait and play an important role in aquaculture. Artemia eggshells are iron-containing lipoproteins, which cannot be digested by young fish and shrimp. Therefore, it is generally necessary to hatch Artemia larvae first, and then feed the larvae as bait. The hatched egg shells and larvae are not easy to be completely separated, and it is easy to cause part of the hatched larvae to be lost with the egg shells, or the egg shells and larvae are eaten together, resulting in intestinal obstruction and death of fish and shrimp larvae. Artemia eggs can be fed directly after shelling, and larvae can also be hatched. Since there is no egg shell, the energy consumption when the larva breaks the shell can be reduced, which is conducive to retaining more nutrients. In fish and shrimp nursery, the cost of Artemia eggs often accounts for 50%-70% of the cost of the nursery. Through the method of shelling, the hatching rate can be improved and Artemia larvae can retain more nutrients. At the same time, a large number of low-quality eggs with low hatching rate can be used to reduce the cost of seedlings, which is of great significance to the nursery.

At present, chemical methods are mostly used for shelling Artemia eggs, that is, sodium hypochlorite and sodium hydroxide solution are used to dissolve the egg shells. After shelling, the reaction cannot be terminated immediately. It is necessary to remove the shelled eggs and clean them to remove residual chlorine. Continue to act on the shelled eggs, causing greater damage; at the same time, the temperature of the solution is easy to rise during the process of shelling, which affects the hatching rate, and cooling measures need to be taken; the operation process has a great impact on the hatching rate, and the process is unstable; and the residual chlorine on the surface of the eggs It is difficult to completely remove, and the peculiar smell of chlorine will affect the feed intake of aquatic seedlings when feeding, and it is often necessary to add food attractants.

Contents of the invention

The invention provides a technical solution for shelling Artemia eggs biologically, aiming at solving the above-mentioned shortcomings of chemical shelling.

1. Soak commercial Artemia eggs in fresh water for 2-4 hours, inflate and stir to make the eggs fully absorb water and swell;

2. Separate Artemia eggs, place them in 10 times the weight of the shelling solution, and stir at 60r/min at a temperature of 30°C;

3. The shelling time is 0.5-5 hours, observe that the color of the eggs gradually changes from brown to orange red, and add a terminator;

4. Inflate and stir for 10 minutes, let it stand still, separate the shelled eggs after stratification, rinse with sea water, and then use it for hatching or direct feeding.

If the fresh water used in the above process is tap water, it is necessary to remove chlorine in advance to reduce the damage to the eggs.

The ingredients of the shelling liquid are: trypsin 0.1%-2%, EDTA 0.02%, and the rest is fresh water.

The components of the terminator are: raw soybean milk prepared from soybeans 10 times the weight of trypsin and water 5 times the weight of soybeans.

In order to obtain a better shelling effect, the shelling time in step 3 is preferably 2-3 hours, and the shelling time of Artemia from different origins is different; the trypsin content in the shelling liquid is preferably 0.5%-1.2%.

Trypsin hydrolyzes the main structure of the lipoprotein in the shell, and other small residual insoluble components are stripped from the surface of the egg membrane by the shearing action of the liquid during the vigorous aeration and stirring process. Soybeans contain trypsin inhibitors, including Kunitz inhibitors and BowmanBirk inhibitors, which can quickly inhibit the activity of trypsin in the shelling solution and protect the egg membrane from damage. It is not only simple and easy to use in the form of raw soybean milk Can reduce costs.

Compared with prior art, the beneficial effect of the present invention:

The invention belongs to the biological method of shelling, the raw materials used are all natural products, no chemical raw materials are introduced, there is no chemical pollution to the shelled eggs, no adverse effect on subsequent hatching or direct feeding, the operation difficulty is reduced, and the shelling effect is stable.

Detailed ways

The present invention will be further described in detail through examples below, but the present invention is not limited to the following embodiments.

Example 1:

1. Soak 500 grams of Artemia eggs in fresh water for 3 hours, inflate and stir to make the eggs fully absorb water and swell. If the fresh water used is tap water, it is necessary to remove chlorine in advance to reduce the damage to the shelled eggs.

2. Separate Artemia eggs, place them in 5 liters of shelling solution, and stir at 60 r/min at a temperature of 30°C. The ingredients of the shelling liquid are: trypsin 0.8%, EDTA 0.02%.

3. Shelling time is 2 hours, when the color of eggs gradually changes from brown to orange red, add terminator. The ingredients of the terminator are: raw soybean milk prepared from 400 grams of soybeans and 2 kilograms of water, and the soybean trypsin inhibitor in it can effectively inhibit the activity of trypsin and prevent it from destroying the egg membrane.

4. Place the inflatable head at the bottom of the solution, open the air flow until the solution is in a tumbling state, inflate and stir for 10 minutes, and let it stand still. After the solution is stratified, separate the shelled eggs, and rinse them with sea water for incubation. or direct feeding. Because the activity of pancreatic enzymes has been inhibited, and the calcium and magnesium ions in seawater can also inhibit its activity, it can no longer damage the egg membrane after being diluted with seawater, and it is harmless to Artemia larvae and fish and shrimp seedlings, saving a lot of use Time and labor for repeated cleaning.

Embodiment 2: the impact of different shelling methods on the hatching of Artemia eggs

Using the same batch of Artemia eggs produced in Shandong, under natural light irradiation, salinity 30‰, temperature 28°C, incubation time 24h, and other conditions consistent, take the shelling rate corresponding to the two methods at different treatment times and the hatching rate of the corresponding shelled eggs, and compared the effects of two different shelling methods on the hatching of Artemia eggs, the results are shown in Table 1. Among them: the control group is normal hatching without shelling; the chemical method is the combination of sodium hypochlorite and sodium hydroxide; the hatching rate of the two shelling methods is the hatching rate of shelled eggs.

Table 1 Effects of different treatments on the hatching of Artemia eggs

In the chemical method of shelling, the hatching rate of shelled eggs is negatively correlated with the shelling rate. The longer the shelling time, the higher the shelling rate and the lower the hatching rate. Although the hatching rate of shelled eggs when the shelling rate is low is higher than that of the control group, there are still a considerable part of the eggs that have not been shelled at this time, so the overall hatching rate of the eggs is small; when the shelling rate is completely removed, the overall hatching rate Lower than normal hatch. Adopting the method of the present invention to remove shells has mild effect and little damage to eggs, and the hatching rate of shelled eggs is still high when the shelling rate is high, so that the overall hatching rate of eggs is greatly improved, and it can be directly fed or used for hatching Both are suitable.

Claims (1)

1. a shelling method of Artemia ovum, is characterized in that: comprise the steps, (1) Soak commercial Artemia eggs in fresh water for 2-4 hours, inflate and stir to make the eggs fully absorb water and swell; (2) Separate Artemia eggs, place them in 10 times the weight of the shelling solution, and stir at 60r/min at a temperature of 30°C; (3) The shelling time is 0.5-5 hours, and when the color of the eggs is observed to gradually change from brown to orange red, add a terminator; (4) Inflate and stir for 10 minutes, let it stand still, separate the shelled eggs after layering, rinse with sea water, and then use them for hatching or direct feeding; The ingredients of the shelling liquid in step (2) are: trypsin 0.1%-2%, EDTA 0.02%, and the rest is fresh water; the ingredients of the terminator in step (3) are: soybeans 10 times the weight of trypsin and 5 times the weight of soybeans Raw soymilk prepared with water.