JPH04304838A - Method for processing meats - Google Patents

Abstract

PURPOSE:To process half-raw meat food capable of storing over a long period even at ordinary temperature. CONSTITUTION:A half-raw meat food such as beefsteak is subjected to vacuum- packaging into a packaging container (bag) using a plastic film and high- pressure sterilization utilizing high hydraulic pressure higher than 1000 atmospheric pressure is applied at >=60 deg.C and simultaneously post heating treatment higher than 60 deg.C is carried out at atmospheric pressure after high pressure treatment.

Description

[Detailed description of the invention]

0001

[Field of Industrial Application] The present invention relates to a method for processing meat using high-pressure sterilization in which hydrostatic pressure of 1000 atmospheres or more is applied to the processed material. This invention relates to a method for processing meat that allows it to be stored at room temperature for a long period of time without impairing its flavor.

0002

[Prior Art] Conventionally, semi-raw meat foods such as beef steak, roast beef, bonito and seared beef could not be stored for a long period of time, let alone at room temperature or even when chilled. Needless to say, this is due to the proliferation of microorganisms present on the raw parts and surfaces of the meat. Generally, it is said that if the number of microorganisms exceeds 105/g, it is unfavorable in terms of food hygiene, and the number of microorganisms on the order of 104/g or less is considered to be edible.

[0003] Storage and distribution at low temperatures can delay the growth of microorganisms, but it is not a fundamental improvement measure, and the shelf life of semi-raw meat products is only 3.
It was short, about 4 days.

[0004] These microorganisms can be sterilized by heating, but heating to conditions that kill the microorganisms will denature the proteins and lipids in the meat, resulting in the loss of the unique flavor of semi-raw meat foods. The product loses its value as a product. On the other hand, although it is possible to suppress the growth of microorganisms by freezing, the texture of the food is significantly impaired due to the occurrence of so-called drip, in which the water in the frozen food is released from the food when it is thawed. Due to problems, this technology is also not available.

By the way, in recent years, 1.
Technologies for processing and sterilizing foods by applying hydrostatic pressure of over 1,000 atmospheres have been developed, and some have already begun to be put into practical use.

[0006] According to this high-pressure sterilization technology, high pressure is basically applied to the processed material as an alternative to conventional heat treatment, so it is thought that it is possible to sterilize food without impairing its raw flavor. . The applicant applied this technology to the processing of semi-raw meat foods and filed Japanese Patent Application No. 1-164551.

[0007]

[Problem to be Solved by the Invention] The present inventors further studied this technology and found that the above-mentioned patent application No.
It has been found that with the technique of No. 164551, sufficient preservability cannot be obtained in some cases. That is, the above-mentioned patent application No. 1-
The technology of No. 164551 reduces storage and distribution after processing by 7 to 1
It is assumed that the process is carried out at a low temperature (chilled) of around 0 degrees Celsius, and even if it is processed under sufficient pressure conditions using this technology, if it is stored and distributed at room temperature, microorganisms may develop. It has bred.

[0008] The inventors of the present invention conducted intensive research into the cause of this problem and found that the technology and conditions described in the above-mentioned Japanese Patent Application No. 1-164551 have almost no bactericidal effect against some bacteria such as heat-resistant spores. The surviving spores etc. germinate during storage.
It was bred.

Accordingly, the present invention provides a method for processing meat that does not impair the flavor of semi-raw meat foods and allows them to be stored and distributed at room temperature.

0010

[Means for Solving the Problems] That is, in the present invention, a semi-raw meat food is subjected to isostatic pressure treatment at a temperature of 60°C or higher after being deaerated or vacuum packed, and then post-heated at a temperature of 60°C or higher under normal pressure. This is a meat processing method characterized by processing.

Further, in the present invention, the hydrostatic pressure treatment and the post-heat treatment are preferably carried out at a temperature of 70° C. or lower.

0012

[Function] According to the method of the present invention described above, microorganisms existing on the surface or inside of the object to be treated are effectively sterilized by high-pressure treatment and post-heating, and the object can be stored and distributed at room temperature.

[0013]

EXAMPLES The present invention will be explained in detail below.

[0014] Semi-raw meat foods to be processed in the present invention include those that have been cooked near the surface by heating, but the inside is still raw. in particular,
These include beefsteak, roast beef, bonito, and seared beef.These foods are cooked through heat denaturation to bring out the umami flavor, and the raw parts of the food are left behind to bring out the raw flavor of the food. It is something that is kept alive.

[0015] The above-mentioned heating cooking may be performed by either direct heating or indirect heating. This cooking of the food surface by heating is necessary not only to bring out the flavor but also to improve the appearance of the food.

The high-pressure treatment used in the present invention involves applying a hydrostatic pressure of 1,000 atmospheres or more to the object to be treated, such as food, and can be carried out using, for example, an apparatus disclosed in JP-A-61-82933. These devices apply pressure to the workpiece using liquids such as water, hexane, toluene, heptane, xylene, acetone, etc. as a medium, and the workpiece is prevented from coming into contact with these media and the pressure is not applied It is preferable that the material is hermetically sealed in a plastic packaging container or the like that can sufficiently transmit the information.

Specifically, bag-shaped containers made of plastic films such as polyethylene, polypropylene, and polyethylene terephthalate are suitable.

[0018] This packaging container has an intervening layer such as nylon, polyvinylidene chloride, ethylene-vinyl acetate, etc. for storage after processing, distribution suitability (impact resistance, puncture resistance), prevention of oxidative deterioration, etc. saponified polymer, metal foil,
It is preferably made of a material that includes a gas barrier layer such as a metal vapor deposited layer, and an outer layer made of a resin such as stretched polypropylene or polyethylene terephthalate to provide sealing properties when forming a bag.

[0019] The object to be processed is preferably packaged in the above-mentioned packaging container under vacuum or degassing. In other words, if a gas such as air is present, this gas absorbs pressure and reduces efficiency. Also, this gas dissolves into the object to be processed, and when the pressure is released, it is suddenly released from the object to be processed, causing the object to be processed. This is because there is a risk that it may be destroyed or the pressure may not be sufficiently transmitted to the object to be processed.

[0020] The high pressure treatment is carried out at a temperature of 60°C or higher. This is because, as is clear from the experimental results described later, a sufficient sterilization effect can be obtained by carrying out the treatment at this temperature.

[0021] The time of high-pressure treatment does not have much effect on the sterilizing effect. This is because it has been found that the number of viable bacteria rapidly decreases immediately after pressurization, and thereafter the decreasing curve becomes gentle. This rapid decrease generally occurs over a period of 2 to 3 minutes rather than a few seconds, although it varies depending on the type of bacteria and environment. Therefore, from the viewpoint of increasing treatment efficiency and reducing costs, it is preferable to perform the pressurization treatment for a short time of about 5 minutes.

Further, in the present invention, after the high-pressure treatment, a post-heat treatment at 60° C. or higher is performed under normal pressure. This is also because, as is clear from the experimental results described below, a sufficient sterilizing effect can be obtained by performing the post-heating treatment at this temperature. The post-heating treatment can be carried out by heating methods such as steam, oven, microwave, etc. However, for reasons such as thermal conductivity temperature adjustment, ease of uniform heating, and simplicity of the equipment, for example, it is necessary to package the object to be treated. Soak it in warm water while
A so-called boiling method is preferred.

[0023] The above-mentioned high pressure treatment and post-heat treatment
It is desirable to carry out at a temperature of 0° C. or lower. That is, if the temperature exceeds this temperature, the protein in the raw part of the semi-raw meat food that is the object of the present invention will be thermally denatured, and the raw flavor will be lost.

[0024] Also, the pressurizing pressure is 3000Kg/cm2
Above, preferably 4000Kg/cm2 or above. If the pressure is lower than this, some microorganisms cannot be sufficiently sterilized, and the reliability of the sterilizing effect becomes less reliable.

<Experiment 1> Commercially available beef thigh meat with a thickness of 15 mm
The sample was sliced to a thickness of about 100 g. The surface of this sample was sprinkled with salt and pepper as appropriate, and then heated and cooked on both sides for 20 seconds each on a hot plate at about 225°C.

[0026] This sample was vacuum-packed in a bag-like container with a size of 150 mm x 170 mm, which was made using a packaging material consisting of nylon (15 μm)/unstretched polypropylene (50 μm).

[0027] This package was treated under different high-pressure treatment conditions, and the effects on the sterilization effect were observed with and without heat treatment under normal pressure before and after the high-pressure treatment. Note that the high-pressure treatment was performed at a temperature of 30° C. so as to maintain a predetermined pressure for 20 minutes. In addition, the pre-heating treatment and the post-heating treatment were performed using a boiling method, and the treatment conditions were 60°C.
℃ for 20 minutes.

[0028] The number of viable bacteria immediately after all treatments are completed,
After storing it in a bag-like container at 35° C. for 2 weeks, the number of viable bacteria was measured according to a conventional method.

The results are shown in Table 1. Here, for those in which no microbial proliferation (occurrence of colonies) was observed, it was written as "<10" (the same applies to Tables 2 to 4 described later). In addition, in the "Evaluation" column, "◎" indicates that the storage stability was sufficiently good, and "○" indicates that the storage stability was good.
, ``△'' indicates that the food has been preserved to the extent that it can be eaten.
Inedible items are indicated with an “×” (Tables 2 to 4 below)
is the same).

[0030]

[Table 1]

<Experiment 2> The experiment was conducted in the same manner as Experiment 1, except that the high pressure treatment was performed at a temperature of 50°C, and the conditions for the preheating treatment and postheating treatment were 50°C and 20 minutes. . The results are shown in Table 2. In addition, some post-heating treatments were performed at 80°C and 20°C.
The results obtained in minutes are also shown.

[0032]

[Table 2]

From the results in Tables 1 and 2, it can be seen that the conditions of Experiments 1 and 2 were not sufficient because the bactericidal effect was not stable. In addition, among the above-mentioned products, in the product (No. 2-19) in which the post-heat treatment was performed at 80°C, the raw portion was thermally denatured and the raw flavor was impaired.

<Experiment 3> The experiment was conducted in the same manner as Experiment 1, except that the high pressure treatment was performed at a temperature of 60°C, and the conditions for the preheating treatment and postheating treatment were 60°C and 20 minutes. .

The results are shown in Table 3. For comparison, the results of measuring the number of bacteria in the raw state without prior cooking are also shown. Furthermore, storage after treatment at 10℃
The results of observing the number of microorganisms after 4 weeks are also shown.

[0036]

[Table 3]

According to the above results, if post-heating is not performed after high-pressure treatment, storage at high temperature (35° C.) is necessary even if the processing conditions do not pose a problem when stored at low temperature (10° C.). The proliferation of microorganisms was observed (No. 3-8, 3
-10, 3-12).

<Experiment 4> The experiment was conducted in the same manner as Experiment 1, except that the high pressure treatment was performed at a temperature of 70°C, and the conditions for the preheating treatment and postheating treatment were 70°C and 20 minutes. .

The results are shown in Table 4. For comparison, the results of measuring the number of bacteria in the raw state without prior cooking are also shown. Furthermore, storage after treatment at 10℃
The results of observing the number of microorganisms after 4 weeks are also shown.

[0040]

[Table 4]

[0041] What was obtained from this experiment 4 was:
In both cases, the raw flavor of the meat was slightly impaired, and it was determined that there was an extremely high risk that the flavor would be impaired if the meat was heated any further.

Furthermore, according to the above results, as in Experiment 3, even if the processing conditions are such that storage at low temperatures (10°C) causes no problems, microbial growth will occur if stored at high temperatures (35°C). It was recognized (No. 4-2, 4-3).

From the above experiments, the following was found.

(2) Products subjected to preheating treatment are inferior in sterilization effect to those not subjected to preheating treatment, and cannot be said to be effective for sterilization. This is because preheating promotes the proliferation of microorganisms, and the number of bacteria before high-pressure treatment increases.Also, it is better not to perform preheating because the conditions of heating and pressurization, which are disadvantageous to bacteria, are higher than high pressure. It is thought that the sterilization effect is enhanced by the rapid changes in the environment for the bacteria that occur all at once during the treatment.

[0045] When the temperature of high-pressure treatment is 50°C, the number of viable bacteria immediately after treatment is large, and this cannot be said to be a sufficient condition.
℃, the number of bacteria immediately after treatment is small, which is good.

[0046] Items that were subjected to post-heat treatment after high-pressure treatment had a very small number of viable bacteria after being stored at 35°C compared to items that were not subjected to post-heat treatment. Endure.

[0047] Therefore, it has been found that a sufficient sterilizing effect can be obtained by performing high pressure treatment at a temperature of 60°C or higher and, after the high pressure treatment, performing a post-heat treatment at 60°C or higher under normal pressure.

[0048] Also, high pressure treatment and post-heat treatment were carried out at 70°C.
It has also become clear that it is undesirable to carry out the process at a temperature exceeding 1000 ml because it impairs the raw flavor of the meat.

[0049]

[Effects of the Invention] As described above, the present invention is a processing method that allows semi-raw meat foods to be distributed and stored at room temperature while retaining their raw flavor. This made it possible to preserve these foods for long periods of time.

Claims (2)

[Claims] Claim 1: A semi-raw meat food is degassed or vacuum packaged, subjected to isostatic pressure treatment at a temperature of 60°C or higher, and then subjected to post-heat treatment at a temperature of 60°C or higher under normal pressure. ,
Meat processing methods. Claim 2: Hydrostatic pressure treatment and post-heat treatment at 70°C.
The method for processing meat according to claim 1, characterized in that the processing is carried out at a temperature of: