JPH02113861A - Production of food - Google Patents

Abstract

PURPOSE:To simultaneously carry out cooking and sterilization at a low temperature in a short time by irradiating a food hermetically sealed with an infrared- permeable and gas-impermeable plastic inner packaging material to be processed with infrared rays. CONSTITUTION:A food hermetically sealed with an infrared-permeable and gas-impermeable plastic packaging material (e.g., polyethylene terephthalate or polyolefin) to be processed is irradiated with infrared rays. Furthermore, part of the packaging material is preferably a plastic film having a metal layer.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to a method for producing food, and specifically to a method for simultaneously cooking and sterilizing food.

(Prior Art) Conventionally, in the field of food processing industry, for the purpose of cooking and sterilizing food, food is sealed in a film or container and immersed in hot water at 85 to 95°C for 45 to 90°C. There are two main methods: the boil method, in which the processed food is cooked for 15 to 30 minutes, and the retort method, in which the food to be processed is sealed in a container, placed in a steam pot, and cooked under pressure at a temperature of 115 to 132°C for 15 to 30 minutes. Ru. Typical foods of the former include seasoned fried foods, boiled wild vegetables, etc., and typical foods of the latter include bagged curry, canned food, etc.

On the other hand, in the case of roasted seaweed, stacking and baking multiple sheets of raw seaweed will cause uneven baking, so it is best to heat each sheet one by one to make roasted seaweed, and then place one or more sheets into a film peck. It is.

(Problems to be Solved by the Invention) However, in all conventional cooking sterilization methods, processed foods are heated at high temperatures for long periods of time, resulting in significant deterioration of their components. When cooked for a long time, there was a problem in that the protein deteriorated significantly and the taste inevitably changed. Moreover, in either method, a large amount of heat or heat and steam is released into the working space during cooking and sterilization, so there is a problem in that the workers are forced to work under harsh working conditions at high temperatures.

On the other hand, in the case of foods such as roasted seaweed that are packaged after being heat-processed, there is a problem that secondary contamination due to airborne bacteria occurs between the time of heat-processing and the time of packaging. 2. Therefore, it is an object of the present invention to make it possible to cook and sterilize foods at low temperatures and in a short time, while at the same time making it possible to prevent secondary contamination and improve the working environment.

(Means for Solving the Problems) As a means for solving the above problems, the present invention is characterized by irradiating infrared rays onto a processed food sealed with an infrared transparent and gas impermeable plastic packaging material. The present invention provides a method for producing food products.

The packaging material may be in any form, such as a film, a container, or a container, depending on the form of the food to be processed.

Further, the film may include a single film coating film, a laminate film, a laminar film,
Any plastic film such as a metallized film can be used, and the laminated film contains a metal foil such as aluminum or silver after lamination. These can be used alone or in combination of two or more types, but when a plastic film with a metal layer is used alone, such as a metal-deposited film or a laminate with a metal layer, the metal layer may be used as a part of the plastic film. It is preferable to provide a portion without. This is because if the entire processed food is coated with plasti or kufilm, which has a metal layer on the entire surface, infrared rays will not be able to penetrate inside.

Further, when the packaging material is in the form of a container, either the container body or the lid may be composed of a laminate having a metal layer, and a filler such as talc or calcium carbonate may be added to the forming raw material. It may also be formed by molding.

As the material for the plastic, any material used for food packaging can be used, such as polyethylene terephthalate, polyolefin, polyvinylidene chloride, polyethylene cellophane, moisture-proof cellophane, etc. Specifically, OPP, PET-25, TUX
Fc, 0N-25, OP/CP, ON/CP, MSTH
D-78, VOP/CPP, HC/OP,
T A F / 5 H, 0N-LLDPE, l, -
Examples include LDPE.

The present inventor, Rimi, for example, filed Utility Model Application No. 62-2230.
It can be carried out using the infrared cooking device described in the specification, but it is not limited to this device.In short, it can be carried out using any heating device as long as it emits infrared rays. can do. As shown in FIG. 1, the infrared cooking device basically includes a wire heater 1 and a plurality of pairs of infrared lights arranged in two rows facing each other vertically, and arranged on the back of each heater 1. A reflector plate 2 having a substantially arc-shaped cross section, and 1! disposed between both heaters. The above-mentioned upper and lower infrared heaters 1 are disposed on the support means 3 so as to be movable in 21 directions, so that the distance between the north and downward heaters can be adjusted.

The support means 3 includes a wire mesh pond removably installed or fixed to the cooking device main body 5, and a pair of chain conveyors that move in the space between the heaters.
Any material such as M number of trays or wire mesh can be used. It is preferable that the wire mesh or tray has a glossy surface or is coated with black paint so that infrared rays can pass therethrough.

Further, the infrared heater 1 is normally controlled to have a temperature within a range of 250 to 500°C. This is 250
If the temperature is less than 500'C, the effect unique to infrared rays, especially far infrared rays, which penetrates into the inside of processed food and directly heats it cannot be sufficiently obtained, and if it exceeds 500'C, the total radiant energy of the heater will increase. However, this is because power consumption increases and the energy-saving effect of using infrared rays is lost. Furthermore, when the temperature of the infrared heater is set in this manner, infrared rays having a lower limit of wavelength within the range of approximately 1.5 μm or more and less than 2.5 μm are emitted, allowing efficient cooking and sterilization.

The reflector is made of a material with high infrared reflectivity, such as aluminum.

(Function) As shown in Fig. 2 (a), the processed food 4 is sealed with an infrared-transparent, gas-impermeable plastic packaging material 6.7, and this is placed in the infrared cooking device shown in Fig. 1. When infrared rays are irradiated, the infrared rays that have passed through the packaging materials 6 and 7 enter the inside of the processed food 4, thereby directly heating the processed food and sterilizing the processed food at the same time as cooking.

Examples of the present invention will be described below.

(Example 1) Stack 10 quarter sheets of commercially available seaweed sheets,
Two-layer laminated film 5a, 5 of m-thick nylon film and 70 μm-thick polyethylene film
b was placed in a bag 6 having a width of 20 cm and a length of 30 cn+ formed by pasting them together as shown in FIG.

Next, in the infrared cooking device of FIG. 1, the interval between the upper and lower infrared heaters 1 was set to 26 cm, and a black aluminum net was placed as a support means 3 in the center between the upper and lower heaters, and a black aluminum net was placed on the aluminum net. Place the wrapped seaweed on top, heat the heater at 300°C, and heat the oven at 65°.
It was heated at C for 10 minutes to make roasted seaweed.

The radiation characteristics of the infrared heater are shown in the table below. This radiation II dimension characteristic was measured using a powdered radiator of an infrared heater under conditions of a temperature of 296° C. and a measurement distance of 20 cm.

Wavelength range Infrared amount (W/cm") 0.7-3.
5μm 1. ]8X10"1.5~14μfi+
8.58X1.0-37~14μm
4.32X]0-37~30μm 4.38
X 10-” When I took out the roasted seaweed from the bag and observed and tasted it, I found that all 10 sheets were baked evenly, and the color, gloss, and flavor of the baked seaweed were much better than the conventional one that was baked one sheet at a time. It was getting better.

In addition, while the roasted seaweed was stored in a bag at room temperature for 6 days, commercially available seaweed used as a raw material was stored as a comparison sample 1 under the same conditions for 6 days, and the general viable bacterial count and coliform bacteria were determined. Regarding the number, Food Sanitation Law Inspection Guidelines I, IT
The test was conducted based on the method of The number of coliform bacteria was tested using the plate method and BGLB fermentation tube method. The results are shown in Table 1.

From the results in Table 1, it can be seen that according to the method of the present invention, it is possible to quench a plurality of sheets in a packaged state in a stacked manner, and also to sterilize them.

(Example 2) A raw mackerel was cut into two halves, and the two halves were wrapped in film and stored frozen, while the other half was pasted with two layers of 15 μm thick nylon film and 70 μm thick polyethylene film. Place it in a bag 20cm wide and 30cm long made of laminated paper, and use an automatic vacuum packaging machine to package it into 73cm bags.
Vacuum packaging was performed under reduced pressure of Hg.

Next, using the infrared cooking device used in Example 1, the vacuum-packed raw mackerel was placed on the aluminum net and cooked for 10 minutes at a heater drying temperature of 1 f400'c and an internal temperature of 85°C.

Place the cooked mackerel in the refrigerator in its package at +10°
The raw mackerel that had been refrigerated for 6 days at -20°C and then frozen for 6 days at -20°C was used as Comparative Sample 2 and tested for the number of viable bacteria and the number of coliform bacteria in the same manner as in Example 1. The results are shown in Table 2.

From the results in Table 2, mackerel sterilized by the method of the present invention is
It can be seen that it is sterilized in the packaged state, and that secondary staining due to bacteria etc. is completely prevented even when stored refrigerated. It was confirmed that the mackerel was completely cooked using infrared rays.

In the above embodiment, a two-layer laminate of a nylon film and a polyethylene film is used as the infrared-transparent, gas-impermeable plastic packaging material, but the invention is not limited to this. Various plastic materials can be used. In this case, the higher the infrared transmittance of the material used, the more advantageous it is, but even materials with low transmittance can be used by appropriately setting the cooking time.

Table 3 shows the results of determining the infrared transmittance of these representative materials. Note that this transmittance is not an absolute value but a relative value, and the test was carried out using a cube-shaped ham 10 whose negative side is 5cI11, as shown in FIG.
temperature sensor 11 at the len+ position from its upper end.
The infrared heater 1 equipped with the reflector 2 used in the above embodiment was placed 22 cm from the upper end of the ham. The temperature sensor 11 detects the temperature rise when the plastic film 12 is placed and heated at a heater temperature of 300'C for 5 minutes, and the transmittance is the temperature when heated without the plastic film 12. The degree of -H was determined from the degree of temperature rise when the film was placed and heated under the same conditions.

(Margin below) Table 3 PP ET-25 UXFC ON-25 0P/CP ON/CP MsTHD-73 VOP/C, P PI (C10P AF15H ON-LLDPE 1, -LDPE (Effects of the invention) The above As is clear from the description, according to the present invention, the following excellent effects can be obtained.

That is, since sterilization is performed simultaneously with direct heating by irradiating infrared rays onto the processed food sealed in a packaging material made of plastic that transmits infrared rays, cooking sterilization can be performed at low temperatures and in a short time.

In addition, since it uses infrared rays, it can be carried out at a low ambient temperature, and cooking sterilization does not change the taste or ingredients of the food, making it possible to produce foods with excellent taste! i2 can be built.

Furthermore, since the food is cooked and processed while being packaged in a non-air permeable or low air permeable packaging material, secondary contamination by bacteria etc. after cooking and sterilization can be completely prevented. Therefore, not only can the food be kept for a long time, but it can also be handled very hygienically.

Furthermore, since the heating is performed directly with infrared rays, the ambient temperature is very low, and commercially available plastic films and sheets with relatively low heat resistance can be used.

Furthermore, since it is heating by radiation, there is very little energy loss compared to conventional heating using hot water or steam, that is, heating by convection or heat transfer.Furthermore, since there is no release of large amounts of heat or steam, it is possible to It can prevent "-H" in quality and humidity, and can significantly improve the working environment.

Furthermore, by using laminate in the packaging material, it is also possible to impart decorative functions. Furthermore, by using the packaging material for the container, packaging can be adjusted according to the type of food.

[Brief explanation of drawings]

Fig. 1 is a schematic sectional view of an infrared cooking device used in the actual method of the present invention; Fig. 2 is a sectional view showing various packaging materials;
FIG. 3 is an explanatory diagram showing the measurement status of the transmittance of 6 types plus sheep film. 1 - Optical external ray heater, 2 - Reflector, 3 - Support means, 4 - 1
Processed leather food.

Claims (5)

[Claims] (1) A method for producing a food product, which comprises irradiating a processed food sealed with an infrared-transparent, gas-impermeable plastic packaging material with infrared rays. (2) The method for producing a food product according to claim 1, wherein the packaging material is in the form of a film or sheet. (3) The method for producing a food product according to claim 1, wherein a part of the packaging material is a plastic film having a metal layer. (4) Claim 1, wherein the packaging material comprises a container body and a lid.
Method of manufacturing the food described. (5) The method for producing a food product according to claim 1, wherein either the container body or the lid is a plastic film having a metal layer.