JPS63207356A - Production of cooked rices - Google Patents

Abstract

PURPOSE:To obtain the titled readily cookable cooked rices having puffy voluminous feeling and excellent sense of eating and preservable for a long period, by heating a blend containing rice and water with steam in a special package body and hermetically sealing the package body under germ-free condition. CONSTITUTION:A blend containing rice and water is heated with steam in a package body having an opening part capable of flowing air therethrough under germ-free condition, such as a bioclean room, to afford the aimed cooked rices. Further, the moisture content of the rice is preferably 20-50% before heating with the steam and the rice is preferably semigelatinized rice. Furthermore, the above-mentioned blend preferably contains a fat or oil or organic acid and the package body is preferably turned over and held before the temperature of the blend after hermetically sealing attains <40 deg.C.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides cooked rice that has a long shelf life and can be easily eaten by heating it in a microwave oven, hot water bath, or frying pan. Regarding manufacturing methods.

[Conventional technology]

Traditionally, cooked rice that can be eaten simply by heating it in a microwave or hot water bath has included retort-processed red rice and rice.

These retort rice products are made by storing raw rice or water-soaked rice and water in a heat-resistant bag, sealing it, and heating it to 200°C in a retort bag.
The product was subjected to pressure and heat treatment for about a minute and then cooled to form a product.

However, when conventional retort cooked rice, especially non-glutinous rice, is retorted, the rice grains adhere tightly to each other and polyneem does not form, resulting in fluffy rice that does not stand out. There was also the problem that the texture became sticky rice-like.

In addition, in JP-A-52-44258, a heat-resistant and moisture-impermeable synthetic resin tray is filled with raw rice and a small amount of water, and a heat-resistant and moisture-impermeable lid film is attached to the tray. The mixture is mixed so as to cover the entire upper surface of the tray, and a seal is attached to the periphery of the lid film, leaving some unattached parts on the upper surface of the flange of the tray, and the tray is heated under pressure in a retort pot to cook rice. A method of manufacturing a rice pack is disclosed, which comprises, after sterilization, sealing the cooked rice in the tray by pasting a seal around the lid film on the upper surface of the flange of the tray in the pasting section as well.

However, with this method, after the rice is cooked and sterilized, bacteria invade the tray, making it impossible to store the rice for a long period of time. This method requires sterilization at a temperature of about 0.9°C, which is a complicated process, and has the disadvantage that the texture of the cooked rice becomes glutinous.

Furthermore, in Japanese Patent Publication No. 61-11586, an opening is left in a part of a bag filled with uncooked contents, and the contents are heated by heating the entire bag and contents without restraint under normal pressure. A method for producing a food product is disclosed, which is characterized in that cooking and sterilizing the food product are performed simultaneously, and after heating, the opening is sealed at a relatively high temperature.

However, with this method, after the contents have been cooked and sterilized, they must be sealed at a temperature of around 70°C or above, which kills all bacteria, and for this reason, when the contents are cooled to room temperature, the internal pressure is reduced. I'll do it. As a result, when cooked rice, especially non-glutinous rice, was used as a raw material, the rice grains adhered tightly to each other on the gelatinized rice grain surface and did not become fluffy.

Furthermore, Japanese Patent Publication No. 13899/1989 describes a method for sterilizing cooked foods such as prepared dishes and boxed lunches that need to be preserved without loss of flavor and texture. These are then covered with a covering material such as a plastic film sheet or plastic bag that has holes large enough to allow air to circulate without resistance, and then the whole is heated with steam from a non-pressurized steamer. A method for sterilizing food in which the food is packaged using a tray or the like is disclosed, which comprises performing sterilization, cooling the food under aseptic conditions, and sealing the through holes.

However, according to the above sterilization method, side dishes, bento boxes, noodles, etc.
When sterilizing pre-cooked foods such as eggs and dumplings, it is necessary to fill containers such as trays with roasted rice, making the filling operation complicated and prone to secondary contamination.

[Problem that the invention seeks to solve]

The inventor of the present invention has completed the present invention as a result of intensive research to solve the above-mentioned problems.

Therefore, the purpose of the present invention is to have rice grains that do not adhere tightly to each other, have a fluffy and voluminous feel, and have excellent flavor and texture.
To provide a method for producing cooked rice that has excellent long-term storage stability and can be easily eaten by simply heating it in a microwave, hot water bath, or frying pan.

[Means for solving problems]

The present invention is a method for producing cooked cooked rice, which is characterized by heating a mixture containing rice and water with steam in a package having an opening through which air can circulate, and then sealing the package under aseptic conditions.

The present invention will be explained in more detail below.

(Rice) In the present invention, rice includes semi-pregelatinized rice such as non-glutinous rice, glutinous rice, wild rice, brown rice, and refined products thereof, or semi-cooked or semi-heated products thereof.

Moreover, rolled barley can be added as needed.

In a preferred embodiment of the present invention, the moisture content of rice is reduced to 20
Setting the content to 50% is effective in improving workability and texture. Normally, the moisture content of raw rice is 10 to 18%, and the moisture content can be increased to 20 to 50% by soaking or spraying water, seasoning liquid, organic acid aqueous solution, etc. . If the water content is less than 20%, the texture and hardness of the product will be uneven, the plump and voluminous feel will be reduced, and the shelf life will also be poor. On the other hand, 50%
If the amount is larger than this, the measuring and filling properties of the package will be poor and the work will be difficult.

(Water) The amount of water contained in the package along with the rice varies depending on the moisture content of the rice, but is 10 to 1500% of the rice. That is, it may be added so that the moisture content after steam heating is 55 to 95%.

In the present invention, one or more of seasonings, colorants, fats and oils, and organic acids are further added to rice and water, and this is heated with steam in a package having an opening through which air can circulate,
Preferably, it is sealed under aseptic conditions.

(Oils and fats) Oils include soybean oil, corn oil, cottonseed oil, rapeseed oil,
These include vegetable oils and fats such as palm oil, sesame oil, olive oil, and margarine, and animal fats and oils such as lard, head, and butter, and oils and fats obtained by hydrogenating and fractionating these oils and fats can also be used.

Cholera oil can be added in the form of an emulsion with water and an emulsifier, or can be added as a powdered oil. The amount added is about 0.2 to 20% based on rice.

The addition of oil and fat prevents rice grains from sticking together excessively,
It is possible to prevent rice grains from forming into clumps and to prevent the rice grains from hardening due to steam heating in the next step, resulting in a good texture. Furthermore, when reheating in a microwave oven, fats and oils act as a heat medium, which has the effect of speeding up cooking. This effect is particularly noticeable when preparing cooked rice such as pilaf and chicken rice.

(Organic acids) Organic acids include citric acid, malic acid, fumaric acid, lactic acid,
Refers to ascorbic acid, acetic acid, tartaric acid, etc.

The amount added is about 0.01 to 5.0% based on rice.

Organic acids can be used by soaking rice in the aqueous solution, spraying the rice as an aqueous solution, adding it to seasoning liquid, adding it to the water contained in the package, or blending it into the powdered seasoning contained in the package. It can be used as

Organic acids can promote long-term shelf life, whiten the color, and soften the strange flavor of rice caused by steam heating. Good for white rice.

<Taste sauces) Furthermore, in a preferred embodiment of the present invention, seasoning sauces can be added together with rice and a mixture of one or more of water, oil and fat, and organic acid.

Here, seasoning sauces include pilaf base, curry sauce,
Seasoning powders, pastes, and liquid sauces for chicken rice, gomoku rice, wild vegetable rice, sushi, tamagogai, katsudon, and beef bowl, and contain ingredients such as meat, fish and shellfish, vegetables, and beans. A≦ is fine.

These seasoning sauces can be mixed with the rice and water, sprinkled on top, or dusted so as not to come into direct contact with the rice and water.

(Package) Rice, water, oil, fat, one or more organic acids, and seasoning sauces are then placed in a package having an opening through which air can circulate. The opening may be any opening as long as it allows steam to circulate evenly throughout the package during steam heating and can be sealed in an appropriate manner in a subsequent process, and the package may include one or more openings.

Preferred packaging bodies are tray containers made of heat-resistant synthetic resin or plastic bags made of a laminate of heat-resistant synthetic resin film and/or metal foil.

For example, tray containers are made of polypropylene molded into a tray shape, or have an intermediate layer of vinylidene chloride film.
The upper and lower layers include a tray container with an opening made of a layered polypropylene layer vacuum-formed into a tray shape, or a heat-formed mixture of pulp fiber and heat-resistant synthetic resin.
Alternatively, a tray container without an opening and a tray container in which a portion of the tray container upper lid film (polyester/nylon/polypropylene) is not welded can be used.

In addition, plastic bags are made of polyester/polyethylene/polypropylene laminate materials, dry laminate materials such as polyester/polypropylene, nylon/polypropylene, etc., and are made into bag shapes, with some unwelded parts that are not heat-sealed. Plastic bags can be used.

(Cooking sterilization method) 100 to 2,000 ml of rice, water, etc. are placed in these packages.
1 to 1.000 g of seasoning sauces are added to 100 to 2.000 g of rice and water, and heated with steam.

The steam heating time varies depending on the weight of rice, water, and seasoning sauces in one package, the structure of the steamer, etc., but is generally required to be 10 to 120 minutes.

That is, steam such as wet steam or superheated steam is introduced into a steamer or retort pot, and heated at a temperature of 90 to 110°C for 10 to 10 minutes.
The rice is cooked and sterilized by processing for about 120 minutes.

After that, clean the inside of the steamer or retort pot.
(High Efficiency Particu
(late AirFilter) Replace with filtered sterilized air, and if necessary,
Cooling is performed for 0 minutes, and then the vent hole is sealed in a bioclean room of NASA (American Aerospace Class) standard class 100 to 100.000 (class = dust number of 0.5 μ or more in lft').

Immediately after steam heating, the package can be taken out from the steamer into a bioclean room, and if necessary, after cooling, the opening can be sealed. The temperature at this time is suitably 40 to 70°C.

Furthermore, while the rice is relatively warm at 40°C or above, turn the tray container or plastic bag upside down and
Preferably, it is held for 24 hours.

By inverting and holding the rice, the texture and hardness of the cooked rice become uniform, and the air in the package is absorbed to create a product with a fluffy, polynymous feel.

(Effects of the Invention) The cooked rice produced by the production method of the present invention has a long-term shelf life of 30 days when stored refrigerated at 10°C.

In addition, the packaging does not break during steam heating, and the rice grains stick together tightly and do not form into dumplings, resulting in fluffy rice grains.
-The result is rice with a chewy texture.

Furthermore, cooked rice can be eaten by reheating it in a microwave or in hot water for 2 to 20 minutes, so fast food chains, convenience stores, etc. can omit cooking equipment.

In addition, the cooked rice of the present invention has no unusual odor or taste and has an excellent texture.

(Example) The present invention will be explained in more detail with reference to Examples below.

Example 1 Non-polished rice with a moisture content of 15% was immersed in a 0.1% citric acid aqueous solution for 60 minutes to make the moisture content 32%.

150g of this polished rice with a moisture content of 32%, 130g of water
A mixture of 1 g of powdered oil and fat was placed in a polypropylene tray container, and the tray container and tray container top lid film were sealed, leaving some unwelded parts.

This was steam-heated at 95°C for 32 minutes in a steamer, and then the unwelded parts were heat-sealed in a class 100 bioclean room at a product temperature of 60°C. Thereafter, this tray container was inverted with the product temperature at 45° C. and held for 2 hours to obtain the cooked cooked rice of the present invention. This is 10
After being stored at ℃ for 25 days, the rice was warmed in the microwave for 3 minutes and eaten, resulting in fluffy white rice with a polynymous feel.

In addition, there was no off-flavor or taste, and the food had a freshly baked texture.

Example 2 Neo brown rice (manufactured by Kikkoman, degree of gelatinization 70%) 100g
A mixture of water, soybean salad oil, 140 g of an emulsion of sucrose fatty acid estero epsilon, and 20 g of seasoning for pilaf with ingredients was placed in a polyester/polypropylene plastic bag with an unwelded part that was not heat sealed. Filled.

This was placed in a retort pot and heated with steam at 110° C. for 17 minutes. Furthermore, after steam heating is completed, sterilized air is introduced into the retort pot to eliminate the steam, and the unwelded portion is heat-sealed in a class 1000 bio-clean room to obtain the cooked brown rice pilaf of the present invention. Ta.

When the resulting cooked brown rice pilaf was heated in a microwave for 3 minutes and eaten, it had a fluffy and voluminous exterior texture, no off-flavors, and a freshly cooked texture.

Example 3 Non-polished rice with a moisture content of 15% was soaked in water for 60 minutes to make the moisture content 32%.

150g of this polished rice with a moisture content of 32%, 130g of water
A mixture of 0.1 g of lactic acid, and 2 g of powdered fat and oil was placed in a polypropylene tray container, and the tray container and tray container top film were heat-sealed, leaving some unwelded portions.

This was heated with steam at 95° C. for 32 minutes in a steamer, and when the product temperature reached 60° C. in a class 100 bioclean room, the unwelded parts were heat-sealed. Immediately thereafter, the tray container was inverted and held for 1 hour to obtain cooked rice.

Example 4 Cooked rice was obtained in the same manner as in Example 3 except that 0.1 g of lactic acid was not added.

Example 5 Cooked rice was obtained by processing in the same manner as in Example 3, except that non-glutinous polished rice with a moisture content of 15% was not soaked in water, and instead 120 g of non-glutinous polished rice and 160 g of water were used.

Example 6 Non-polished rice with a moisture content of 15% was immersed in hot water until the moisture content was 5%.
The process was carried out in the same manner as in Example 3, except that 2% non-glutinous polished rice 21 (Ig) and 70 g of water were used to obtain li-processed cooked rice.

Example 7 Cooked rice was obtained in the same manner as in Example 3 except that powdered oil and fat was not added.

Example 8 Cooked rice was obtained in the same manner as in Example 3, except that it was not held upside down.

The workability of these Examples 3 to 8 (measuring and filling time), and the appearance when the cooked rice products of Examples 3 to 8 were stored at 10°C for 25 days and then heated for 3 minutes in a microwave oven (Polyneem Table 1 shows the results of evaluating the texture (hardness, uniformity) and texture (hardness, uniformity).

Further, the cooked rice products of Examples 3 to 8 were further heated at 10°C for 60°C.
It was subjected to a storage test for 1 day. The results are shown in Table-2.

Table-2

Claims (7)

[Claims] (1) A method for producing cooked cooked rice, which comprises heating a mixture containing rice and water with steam in a package having an opening through which air can circulate, and sealing the package under aseptic conditions. (2) The production method according to claim 1, wherein the rice has a moisture content of 20 to 50% before steam heating. (3) The production method according to claim 1, wherein the rice is semi-gelatinized rice. (4) Claims 1 to 3 in which the mixture contains oil and fat
The manufacturing method according to any one of paragraphs. (5) The manufacturing method according to any one of claims 1 to 4, wherein the mixture contains an organic acid. (6) After sealing, the package is inverted and held in this state before the temperature of the mixture becomes less than 40°C, according to any one of claims 1 to 5. manufacturing method. (7) The manufacturing method according to any one of claims 1 to 6, wherein the sealing under aseptic conditions is performed in a bioclean room.