JPS5842741B2 - Method for producing protein liquid and protein powder - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing fat-free protein liquid or protein powder from dried krill.

Krill is a type of zooplankton that is widely distributed in the ocean, and is a shrimp-like crustacean with a body length of about 1 to 7 CrIL, and is mainly known as food for fin whales and white fin whales.

In particular, Neifersia 0 superba (Eu), which lives in the Southern Ocean
The estimated abundance of this species (phasia 5uperba) is said to be several hundred million tons, and it is on the rise as the number of whales decreases.

It is of great significance to use this rich resource for human consumption and to prepare for the expected future shortage of protein sources.

For this reason, research into making krill into food has been conducted in various fields, but no satisfactory results have been obtained yet.

In addition to palatability, the following problems with edibility and preservation have been pointed out as reasons for this delay in research.

(1) Krill is smaller than shrimp, and its shell accounts for 30% of its entire body, making it extremely difficult to thresh it.

For this reason, it is difficult to make a product like muki shrimp, and therefore, in order to effectively utilize only the protein part, it is necessary to elute the fleshy part, but an effective means for this has not yet been found. .

(2) Krill can be eaten as is, but it has a unique odor (amine odor) and taste.

This is not a so-called bad odor, but it is something that people get tired of even when ingested in small amounts, and it is not suitable for large amounts of ingestion.

These odors and tastes are largely due to the highly unsaturated fatty acids contained in the lipids of krill, and the oxidation of these highly unsaturated fatty acids also causes poor storage stability and palatability.

As a method for removing highly unsaturated fatty acids from fish bodies, for example, degreasing with organic solvents such as n-hexane, cyclohexane, acetone, etc. is generally used, but with such methods, the characteristics of the raw materials are lost. I,
In addition to the loss of flavor, the use of organic solvents increases manufacturing costs, and it also has fatal flaws in that it cannot be treated as a natural food under the Food Sanitation Act.

Therefore, if it were possible to remove lipids such as highly unsaturated fatty acids from krill without using an organic solvent, it would be extremely desirable for the production of krill as food.
Such a method is not yet known.

(3) Krill is usually stored raw or boiled and frozen immediately after being caught.

However, krill normally contains 80% water.
This results in a large amount of dripping (d) when thawing frozen products.
Since a large amount of soluble protein contained in krill is transferred to the drip and lost, there is an urgent need to develop a method for effectively utilizing it.

The present inventors have conducted extensive research to solve this problem, and have invented a method for obtaining high-quality fat-free high-protein liquid and high-protein powder from fresh and frozen krill.
52874, but as a result of further research, we came to the knowledge that water-soluble proteins can be effectively extracted using water or salt water even from dried krill, which has a low water content.

The present invention was completed based on this new knowledge,
Dried krill is immersed in water or salt water for a predetermined period of time to elute the fleshy part, the shell of the krill is removed, the eluate thus obtained is heated to form a raw protein coagulum, and the coagulum is then removed. This method consists of obtaining a fat-free protein solution by adding sugar to the protein solution obtained in this way, heating it with stirring to uniformly mix and dissolve it, and then spray drying it by a conventional method. This is a method for producing protein powder by

The dried krill used in the present invention is dried krill immediately after being caught, or raw frozen krill that has been frozen directly after being caught, thawed and dried, etc.
Krill that has been boiled in advance and then dried is not suitable for the present invention.

Furthermore, according to the present invention, the lower the water content of dried krill used as a raw material, the lower the yield relative to solids, and the higher the water content, the lower the yield relative to the entire raw material.

Therefore, the dry krill used as a raw material for the present invention most preferably has a water content of 10 to 50%, but it is also possible to use krill whose water content exceeds this range depending on the case.

When soaking these dried krill, if frozen krill is used as a raw material, it is sufficient to add water, thaw it, and then soak it as it is.

Immersion is usually performed at a temperature below room temperature for 5 to 24 hours.

If stirring or the like is performed during immersion, the objective can be achieved in a shorter time.

It is sufficient that the amount of dipping liquid is at least enough to fully immerse the krill, and stirring or the like may be performed during dipping.

Further, when using salt water as the immersion liquid, it is preferable to use salt water with a relatively low concentration of about 3% in order to reduce the salt content in the product.

Next, the krill shells are removed from the soaking liquid by a method such as filtering or scooping with a wire mesh, and if necessary, the fleshy parts adhering to the shells are further washed off to obtain a krill eluate. .

Steaming for 15 to 30 minutes is then sufficient to heat the eluate.

Due to this heating, fats such as highly unsaturated fatty acids are precipitated as a coagulate along with some proteins, but this can be done using a centrifugal separator, pressure filter (filter press), or vacuum filter (Oliver filter). It can be easily removed by

By the above method, a protein solution containing no fat can be obtained.

This protein solution can be made into a higher quality protein solution by decolorizing it with activated carbon, if necessary.

According to the present invention, a predetermined amount of carbohydrates is added to the protein liquid obtained as described above, heated if necessary, mixed and dissolved uniformly, and then spray-dried using a conventional method to form a protein powder. I can do it.

Carbohydrates added in this case include sugars such as lactose and maltose, starches such as soluble starch, dextrin, starch intermediate decomposition products such as powdered candy, or sugar alcohols obtained by reducing these starch intermediate decomposition products. etc. are used.

The amount of carbohydrates added varies depending on the type of carbohydrates, but
Usually, it is preferable to use an amount of 0.7 to 3 times the protein content in the protein solution.

If the amount of carbohydrates is too small, the hygroscopicity of the protein powder will become significant, which is undesirable from the viewpoint of storage stability, etc. The protein liquid obtained by the present invention has a generally pale yellow appearance and has the aroma and taste of shrimp, so it cannot be seasoned. It is useful as the main raw material for food.

In addition, the protein powder obtained by the present invention has a generally pale grayish-white appearance, a soft shrimp odor and taste, a smooth mouthfeel, and is easily dissolved, so it is useful as a main raw material and an auxiliary raw material in various foods. In addition, for the purpose of improving nutritional value, taste, etc., it can be added to and used in conventional seafood paste products, snack foods where flavor is valued, spices, etc.

In addition, since it does not contain fat, it is less prone to oxidation and has excellent storage stability and palatability.

In addition, according to the present invention, raw materials with lower moisture content are used compared to methods that use freshly frozen products as raw materials, so it is extremely economical not only in terms of transportation but also in terms of storage. This is extremely advantageous since the raw material yield is significantly improved.

About 70% of the solid content of krill is crude protein, and according to the method of the present invention, about 60% of this can be obtained as a protein solution.

Furthermore, the method of the present invention does not involve the addition or treatment of chemicals such as alkalis, acids, organic solvents, etc.

Therefore, the protein liquid or protein powder obtained by the method of the present invention has the excellent advantage of not causing any problems under the Food Sanitation Act.

EXAMPLES Next, the present invention will be explained in more detail with reference to Examples.

Example 1 100 kg of krill with a moisture content of 15% was mixed with 1460 kg of fresh water.
The fleshy parts of the krill are eluted into the dipping liquid by immersing the krill in the liquid for 12 hours at 10°C or lower.

Next, the krill fish bodies are scooped up and removed, and the fish bodies are further washed twice with 235 kg of fresh water to obtain 1660 kg of krill eluate.

By boiling this eluate for 30 minutes, a purple-gray coagulum precipitates.

Next, the coagulated product is filtered through a filter equipped with a furnace cloth, thereby obtaining 1620 kg of fat-free protein liquid (protein content: 2.2%).

Next, by decolorizing this protein liquid with carbon soog, an almost colorless protein liquid can be obtained.

Next, the protein solution obtained here (protein amount 35.6k
g), 69 kg of dextrin (1
．． 94 times the amount), heated with stirring to dissolve uniformly, and then spray-dried to obtain high-quality protein powder 108
You can get kg.

Table 1 shows the component compositions of the protein liquid and protein powder obtained by the above method and the dried krill powder obtained by conventional drying.

Example 2 100 kg of krill with a water content of 40% is immersed in fresh water at 940° C. for 12 hours at 10° C. or lower to elute the fleshy parts of the krill into the soaking liquid.

Next, the krill fish bodies are scooped up and removed, and the fish bodies are further washed twice with 155 kg of fresh water to obtain 1060 kg of krill eluate.

By boiling this eluate for 30 minutes, a purple-gray coagulum precipitates.

Next, the coagulated product is filtered through a filter fitted with a furnace cloth to obtain 995 kg of fat-free protein liquid (protein content: 2.8%).

Next, by decolorizing this protein liquid with 800 g of carbon, an almost colorless protein liquid can be obtained.

Next, the protein solution obtained here (protein amount 27.9k
g), 54 kg of dextrin (1
．． 94 times the amount), heated under stirring to dissolve uniformly, and then spray-dried to obtain a high-quality protein powder of 84.
You can get 5kg.

Claims (1)

[Claims] 1. Dried krill is immersed in water or salt water to elute the fleshy part, the shell of the krill is removed, the eluate thus obtained is heated, and the coagulum formed is then removed. Characteristic method for producing protein liquid. 2. Dried krill is immersed in water or salt water to elute the fleshy part, then the krill shell is removed, the eluate thus obtained is heated, and the coagulated material is removed, and carbohydrates are added to the protein liquid obtained. A method for producing protein powder, which comprises adding, mixing and dissolving, and then spray drying.