JPS6212968B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a novel method for freezing and preserving bivalves, and more particularly, to a method for freezing and preserving bivalves that can retain the same meat quality, flavor, and taste as when eaten raw even after long-term frozen preservation. Conventionally, if clams, clams, freshwater clams, and other bivalves are frozen without opening them with their shells on, the shellfish will die, and as a result, when boiled or grilled, the shells remain closed or the flesh remains even when opened. It is said that it cannot be used because it adheres to the shell and is difficult to eat, so unless it is bought and sold within a short period of time after being collected so that it can be kept alive in water, for long-term storage it is generally opened, shucked and frozen. However, in the case of frozen shelled meat, it takes time to peel it and the taste deteriorates, and when it is used as a partial ingredient in a dish, it is hidden behind other ingredients and its presence cannot be emphasized, and it does not have the appearance of a highlight. The shelled meat is not often frozen and preserved because it gets old. As is well known, the amount of shellfish collected varies greatly depending on the season. Therefore, in order to provide a stable supply of shellfish throughout the year, it is necessary to preserve them for a long period of time by freezing them with their shells on when they can be collected in large quantities.There is also a method of freezing shellfish with their shells on. Some suggestions have been made. For example, JP-A-56-
In the method described in Publication No. 68342, bivalve molluscs are air-blast frozen at -40°C or frozen at -78°C in dry ice while they are still alive after removing sand from them in salt water, and then kept at -20°C or lower for several months in that state. To store and open the shellfish, put the shellfish in water, bring the water to a boil, heat and thaw the shellfish before opening. However, with this method, there is a risk that the meat quality, taste, flavor, etc. when raw will be lost, resulting in cracking of the shell and quality changes during frozen storage.After storage, the shell must be opened by heating, such as boiling in boiling water. The rate of opening of the shell was not sufficient, and it was not a satisfactory method for freezing and preserving the shell with the shell closed. Thus, the present invention allows bivalves to be frozen for a long period of time without any change in quality with their shells closed, thereby retaining the meat quality, flavor, and flavor when eaten raw, and reducing the open shell rate when cooked after storage. The purpose is to provide a method for freezing and preserving bivalves with high
As a result of extensive research and experimentation by the present inventor, this purpose was achieved by heating and sterilizing bivalves to such an extent that they cannot open their mouths, and then using salt water containing one or more of alkaline compounds, sugars, and glycerin. It was discovered that this can be achieved by freezing while immersed in a water injection solution. The present invention will be explained in more detail. First, after collecting bivalves such as clams, clams, freshwater clams, mussels, and scallops, they are washed with seawater or salt water to remove impurities and remove sand before carrying out the method according to the present invention. After removing the sand, it is heated and sterilized to the extent that it does not open. The reason why this is done is to prevent the mouth from opening at high temperatures or for long periods of time because if the mouth is opened by heating at high temperatures or for a long time, the flavor components and nutrients will be lost, and there is a risk that the quality of the meat will deteriorate and the flavor will be impaired. This heating is to sterilize and remove bacteria attached to the surface of the shell. Heating can be done by any method such as immersion in hot water, heating in a gas oven or microwave oven, but immersion in hot water is usually used. In that case, soak in fresh water heated to a temperature of 60 to 100℃ or dilute salt water of about 1 to 5% for several tens of seconds to 10 minutes.
It is recommended to soak for a minute. Select appropriate heating means and conditions depending on the type and size of the shellfish. In the method of the present invention, after heating as described above, the material is frozen while immersed in the following water injection solution. As the water injection solution, a saline solution having a concentration in the range of 0.5 to 3% is used, or a saline solution containing one or more of alkaline compounds, sugars, and glycerin and having the above concentration is used. As the alkaline compound, hydroxides, carbonates, bicarbonates, etc. of alkali metals such as sodium and potassium are used, and sodium bicarbonate is particularly preferably used. It is desirable that the amount of these compounds added is such that the pH of the saline solution to which they are added becomes slightly alkaline, ranging from 7 to 9. Sucrose, fructose, sorbitol, etc. are preferably used as sugars, and the amount thereof is approximately in the range of 2 to 8%, especially 5 to 6%.
It is preferable to set it as approximately. Also, the amount of glycerin is 1
It is preferably in the range of ~5%, particularly around 2-3%. These compounds may be used alone or in combination, and a saline solution containing a combination of sodium bicarbonate and sucrose is particularly preferred. Even if you put the sand-removed shellfish to be frozen in a container in advance and inject the above-mentioned water injection into it and freeze it while immersed, you should also first pour the above-mentioned water injection into the container and freeze it there. Shellfish may be added and frozen while soaked in any order. In this way, even when frozen while immersed in a water injection solution, the meat can be preserved for a long period of time without losing its raw flesh quality, and during cooking and heating, the shells open at a higher rate than when untreated. can. In the method of the present invention, heating and immersion freezing are performed in combination in this order as described above. That is, the sand-removed bivalves are preheated in hot water, a gas oven, a microwave oven, etc. as described above, cooled, and then immersed in the water injection solution as described above to be frozen. By processing in this way, it is possible to preserve the raw meat quality and flavor for a long period of time, and it is also possible to increase the shell opening rate to virtually 100%. The present invention will be explained in more detail with reference to examples below. Example 1 Clams from Lake Hamana were used, and the shellfish were of two sizes: medium (7 to 8 g/fish) and small (5 to 8 g/fish). 300 g of clams were heated by immersing them in hot water at various temperatures as described below, and then cooled with cold water. After placing it in a plastic container, 500 ml of an aqueous solution containing the ingredients listed in the attached table was added to one portion, and the other portion was frozen as is.

[Table] After freezing at -25℃ for 10 days, thawing the clams, placing the clams in a frying pan with a lid on and boiling for 3 minutes to perform a boiling test. A sensory test was conducted to determine the superiority and inferiority of quality.

【table】

[Table] Results (2) Judgment of meat quality and flavor quality (sensory test) Judgment was made by a panel of 16 people who are skilled in food sensory tests.

[Table] From these results, it is clear that preheating and freezing the water injection solution are effective in increasing the shell opening rate and at the same time preventing deterioration of meat flavor. Example 2 A freezing test was conducted using clams (average weight 59 g). (1) Heat 10 clams in hot water as shown below, cool them in cold water, and place them in a plastic bag.
The liquid and the same aqueous solution were added and frozen. After freezing for 10 days, the samples were thawed and a heating test was conducted.

[Table] Effects can be seen by preheating at 70°C for 3 minutes or 80°C for 1 minute. The taste results showed that both flavor and meat quality were very good. Example 3 A test was conducted using 400 g of each clam (approximately 50 to 60 clams). After preheating using a cooking microwave oven model Nasional NE-5500 as described below, the mixture was immediately cooled with water, placed in a plastic bag, and the same liquid as Example 1 was added thereto for freezing and heating tests.

[Table] Effects were observed with 90 seconds of preheating. Furthermore, No.
The flavor and quality of meat were good, except for the meat quality in Nos. 4 and 5, which felt a little tough. Example 4 A test was conducted using 400 g (50 to 60 pieces) of each clam. Gas oven for cooking (Rinnai Konbetsu)
The sample was preheated in the microwave and the freezing and heating tests were conducted in the same manner as in the previous example.

[Table] The effect was recognized in No. 4 and No. 5, and both flavor and meat quality were good.

Claims (1)

[Claims] 1. A bivalve mollusc is heat sterilized to the extent that its mouth does not open, and then frozen while immersed in a saline solution or a saline solution containing one or more of alkaline compounds, sugars, and glycerin. How to freeze bivalves.