JPH0349641A - Cooling and preservation of food - Google Patents

Abstract

PURPOSE:To extremely rapidly and uniformly cool a fish or livestock food to a temperature range for preserving the food by freezing from the surface of the food to about the half of the food at <= the intrinsic freezing point of the food, rapidly thawing the food with a cooling medium corresponding to the intrinsic freezing point and making the whole food into a uniform temperature. CONSTITUTION:For example, when a food is fish, caught mackerel, sardines, etc., are frozen from the surface of fish to about 1/2 thickness of fish with salt brine at -10 deg.C and immediately thrown into ice salt water at about -2 deg.C corresponding to the freezing point of the fish. Then the frozen layer of the outside of the fish is softened and simultaneously cooling is progressed in the interior by latent heat of melting in the circumference. Consequently, the frozen part at the outside of the fish and the unfrozen part in the interior are thermally uniformarized approximately at the intrinsic freezing point of the fish and the fish is extremely rapidly and uniformly cooled into the objective preservation temperature range. Since the frozen part is thawed, there is no fear of growth of ice crystal.

Description

[Detailed description of the invention] [Industrial application field] In the cooling preservation of meat products such as cut beef, pigs, chickens, etc. or animal foods such as sardines, mackerel, horse mackerel, saury, etc.
If the food is stored at temperatures above the freezing point, it takes a long time to reach the desired storage temperature, so the freshness quickly decreases, making long-term storage difficult. On the other hand, long-term storage will be easier if stored under the following conditions.
During cold storage, fine ice crystals are initially produced, but if the low temperature is maintained, the ice crystals elongate to a large size, crushing the structure of the food, and significantly reducing its commercial value. Therefore, the present invention relates to a cooling preservation method that does not have the drawbacks of such cooling preservation and can maintain freshness for a long period of time.

[Conventional technology]

In general, cold preservation of food can be roughly divided into two types: freezing and non-freezing methods.Non-freezing methods include chilled, ice temperature partial freezing, There is a method that has a longer storage period and is better at maintaining freshness than other methods such as the ice method. However, all of these only specify the target storage temperature range, but do not specify the cooling conditions or method for reaching the temperature range, leaving things to chance.

Therefore, when the food is stored at temperatures above the freezing point, such as chilled or frozen storage, there is no formation of ice crystals due to freezing, so defects such as destruction of cell tissue due to ice crystals do not occur, while the initial temperature of the food Since the cooling process from 1 to 3 to reach the desired storage temperature range is very slow, and the storage temperature is above the freezing point, the ability to inhibit biochemical changes in the food is lower than that of partial freezing or freezing methods, and the storage temperature is very slow. It has the disadvantage that it is difficult to maintain freshness over a period of time. In addition, in the case of partial freezing, where the food is stored below the freezing point, the storage temperature is lower than that of chilled or frozen storage, which increases the ability to inhibit biochemical changes in the food, making it possible to maintain freshness for a long period of time. On the other hand, since the cooling of food from its initial temperature to its storage temperature range is extremely slow, microscopic ice crystals initially form between the food's tissues below the freezing point, and these ice crystals gradually grow larger. It is. Therefore, as the ice crystals grow larger and larger, they compress and destroy cell tissues and deteriorate the quality of food.
It has drawbacks that significantly reduce the product value.

[Problem to be solved by the invention]

When storing animal foods such as meat and fish without freezing, it is necessary to cool the food extremely quickly and uniformly to the storage temperature range, and to reduce the length of ice crystals that occur during the cold storage of the food. An object of the present invention is to develop a cooling means that prevents food from being stored for a long time and from deteriorating in freshness.

[Means for solving problems]

In order to achieve the above-mentioned purpose, the present invention provides a method for cooling and preserving animal foods such as foods made by cutting beef, pork, chicken, etc., or fish such as sardines, sakha, horse mackerel, and saury. Before the food reaches the desired temperature range for cold storage, the food is first frozen from the outer surface of the food (solid) to about A using a cooling medium that is lower than its own freezing point. , Promptly thaw the food using a cooling medium equivalent to the freezing point of the food, equalize the temperature of the frozen and unfrozen parts of the food around the freezing point of the food, and store it in the intended storage temperature range of the food. It's a cheat.

[Embodiments and Effects] Now, to explain in detail an example of implementing the present invention, fish such as horse mackerel and mackerel are caught at a fishing ground, stored in a fish hold and transported to a fishing port, and then transported from the market where they were produced. When transporting or storing the fish to the consumer market, immediately after catching it on board, bring it into contact with salt brine at -10°C or lower, and after about 5 minutes have passed until about 20% of the surface of the fish body is frozen, immediately remove the fish body. into salt water, ice, or cold seawater Φ at a temperature of approximately -2°C, which corresponds to the freezing point of . Then, the outer frozen layer of the food (fish body) softens, and at the same time the inside cools down due to the latent heat of fusion of the surroundings, so the outer frozen part and the inner unfrozen part of the food are at the freezing point specific to the food. The temperature is equalized in the vicinity, and the fish body is cooled extremely rapidly and uniformly to the desired storage temperature range. In addition, since the frozen part is thawed, there is no fear of ice crystals forming.

In this way, fish that undergo rapid and uniform storage processing can maintain freshness for about twice as long as compared to conventional techniques, and produce high-quality catches without destruction of cell tissue or freezing denaturation. It is possible to provide goods.

〔Effect of the invention〕

The present invention provides 7 tons of non-frozen storage of animal food, and the cooling of the eggs from the initial temperature of the food to the target storage temperature range is extremely rapid, and the temperature inside and outside of the food (solid) is uniform. In addition, since it can be stored near the freezing point (-1 to 3°C), there is no destruction of cell tissue or freeze denaturation due to the growth of ice crystals that occurs with partial freezing or freezing methods, but compared to chilled storage or storage on ice, The effects of this cooling method are remarkable, such as good freshness and long-term storage.

Participant: Nisshin Gyogyo Stock Company

Claims (1)

[Claims] Before bringing an animal food such as meat or fish to the cold storage temperature range, the first step is to first heat the food from its outer surface using a cooling medium that is lower than its own freezing point. Once frozen to about 1/2, the second step is to immediately thaw the food using a cooling medium at a temperature corresponding to the freezing point of the food, to even out the overall temperature of the food to around the freezing point. A method for cooling and preserving foods, which comprises warming the foods, and then storing the foods in a target storage temperature range as a third step.