JP2024067517A - Production method of rice processed food - Google Patents

Abstract

To provide a method of easily producing a container-packed gelatinous rice processed product.SOLUTION: A production method of a container-packed rice processed food in which a gelatinous rice processed product is packed includes: a liquefaction step of preparing a liquid rice processed product by pulverizing macerated raw rice; a packing step of packing the liquid rice processed product in a container and sealing the container; and a heating step of retort heating the liquid rice processed product packed in the container to gelatinize the liquid rice processed product.SELECTED DRAWING: Figure 1

Description

The present invention relates to a method for producing a packaged rice processed food product filled with a gelled rice product.

In recent years, there has been an increase in demand for rice and a demand for a wider range of uses. One such use is rice gel, which is made by processing rice into a gel.
Patent Document 1 proposes that the physical properties of food, such as water retention, storage stability, and aging, can be improved by adding more than 0.8 times the amount of water to high amylose rice and/or medium amylose rice, heating the mixture, and mechanically stirring the resulting gelatinized product to obtain rice gel, which can be used as a food additive.

Patent Document 2 describes a gel-like material that is obtained by adding more than 1.5 times the amount of water to high amylose rice, heating the rice, and mechanically stirring the resulting gelatinized material.

However, the rice gel described in Patent Documents 1 and 2 did not consider the distribution or productivity of the produced rice gel, and the rice varieties were limited to high amylose rice or medium amylose rice. In addition, the rice gel was used as a processing ingredient or auxiliary ingredient, and was not eaten as is.

Patent Document 3 describes a rice gel production system for producing rice gel, which is equipped with a heating and stirring unit that stirs and heats rice raw materials.
The rice gel production system of Patent Document 3 has a heating and stirring unit disposed in a sealed container, and is equipped with a sealed conveying unit that conveys the discharged gelatinized material to the crushing unit without exposing it to the air, thereby ensuring the shelf life of the produced rice gel. In addition, the heating and stirring unit is equipped with a scraping-type stirring blade that rotates in the sealed container and stirs the rice raw material while scraping off any deposits on the inner circumferential surface of the sealed container, thereby reducing material loss.

JP 2015-65934 A JP 2013-70663 A JP 2022-107785 A

In order to distribute the produced rice gel as an emergency food or preserved food that can be eaten immediately after opening, it must be thoroughly sterilized. Also, the produced rice gel must be individually packaged.
However, rice gel has high viscoelasticity and is sticky, which makes it difficult to handle when filling individual packages. The invention described in D3 is a system that solves the problems of handling and sterilization of rice gel, but it requires special equipment, which increases manufacturing costs.

Therefore, the objective of the present invention is to provide a method for easily producing a gelled rice product in a container with guaranteed shelf life.

The present invention, which solves the above-mentioned problems, is a method for producing a container-packed rice processed food product filled with a gelled rice product, and includes a liquefaction process in which hydrated raw rice is crushed to prepare a liquid rice product, a filling process in which the liquid rice product is filled into a container and the container is sealed, and a heating process in which the liquid rice product filled in the container is gelled by retort heating.
In the present invention, hydrated raw rice is crushed to prepare a liquid rice product, and the liquid rice product is then filled into a container. Unlike gelled rice products, the liquid rice product is not sticky, so it does not stick to cooking containers, and material loss can be greatly reduced. Since no special equipment or parts are required to reduce material loss, production costs can be reduced.
In addition, since the packaged rice processed food filled with the liquid rice product is directly retorted to gel it, which also sterilizes it, it becomes possible to distribute the packaged rice processed food as is after the heating process.

In a preferred embodiment of the present invention, the filling step is a step of vacuum-filling the liquid rice product into a container. By vacuum-filling the liquid rice product into a container, the preservation properties can be further improved.

In a preferred embodiment of the present invention, the container is a container for retort food.

In a preferred embodiment of the present invention, the packaged processed rice food does not require cooking when eaten.
The present invention is particularly useful for emergency food and preserved food in times of disasters, etc.

Further, the present invention which solves the above-mentioned problems relates to a packaged processed rice food produced by the above-mentioned production method.
The packaged rice processed food of the present invention has excellent preservability and the retrogradation of starch after gelatinization is inhibited for a long period of time.

The manufacturing method of the present invention makes it possible to easily manufacture containerized gelled rice products that are easy to distribute and preserve, without requiring special equipment, parts, etc.

1 is a flowchart showing a process for filling a container with liquid rice product, and a flowchart showing a process for filling a container with gelled rice product. Photographs of the containerized rice processed food and gelled rice product that were produced are shown in place of drawings. This is a photograph in lieu of a drawing showing an application example of a mochi-like gelatinous rice product topped with chopped nori and wasabi. This is a photograph in lieu of a drawing showing an example of application of a gel-like rice product similar to mochi, coated with soybean flour. This is a photograph in lieu of a drawing showing an example of application in which creamy gel-like rice processed product is mixed with vegetable powder to make a paste and spread on bread.

The raw rice used in the manufacturing method of the present invention is not particularly limited. For example, raw rice, polished rice, rice with germ, brown rice, germinated brown rice, old rice, broken rice, etc. can be used. In addition, both non-glutinous rice and glutinous rice can be used.

The manufacturing method for the containerized rice processed food of the present invention will be described in detail below.

(1) Hydration Step The production method of the present invention may include a hydration step of adding water to raw material rice.
The water addition step is not particularly limited as long as the raw material rice can absorb water, but is preferably a soaking step in which the raw material rice is soaked in water. Alternatively, a method in which fine water droplets are applied to the surface of the raw material rice using a spray nozzle, shower nozzle, or the like may be used.

The soaking time in the soaking step is not particularly limited and may be, for example, 10 to 120 minutes, 10 to 90 minutes, or 30 to 90 minutes. It can be appropriately adjusted depending on the rice quality, water temperature, etc.
When the water temperature in the immersion step is, for example, 0 to 30° C., 5 to 30° C., 10 to 30° C., or 15 to 30° C., the immersion time can be about 10 minutes to 2 hours.

The volume of water used in the soaking process is not particularly limited, but is preferably 1 to 1.5 times the volume of the raw rice, more preferably 1 to 1.3 times, even more preferably 1.1 to 1.3 times, and particularly preferably 1.1 to 1.2 times.

The hydration process is preferably a process in which water is added to the raw rice so that the weight of the raw rice after hydration is 1.2 to 1.5 times the weight of the raw rice before hydration, and more preferably a process in which water is added to the raw rice so that the weight of the raw rice after hydration is 1.3 to 1.4 times the weight of the raw rice before hydration.

In addition, before adding water to the raw rice, a step of washing the rice in a conventional manner may be included.

(2) Liquefaction Step The manufacturing method of the present invention includes a liquefaction step in which raw rice to which water has been added is crushed to prepare a liquid rice product.
The liquefaction step is preferably a step of pulverizing raw material rice that is soaked in water.

The water used in the liquefaction process may be the same water used in the water-adding process, or new water may be added after draining the water used in the water-adding process.

The weight (g) of water in the liquefaction step is not particularly limited, but is preferably 1 to 7 times the weight (g) of the raw material rice, more preferably 2 to 6 times, even more preferably 2.5 to 5.5 times, and particularly preferably 3 to 5 times.
In addition, the hardness of the rice gel can be controlled by adjusting the amount of water in the liquefaction process. For example, a rice cake-like rice gel can be produced by using three times the weight of water relative to the weight of raw rice. A cream-like rice gel can be produced by using five times the weight of water relative to the weight of raw rice.

In the liquefaction process, the equipment used to crush the raw rice can be a food processor, homogenizer, mixer, kneader, kneader, or commercial grain grinder.

The liquid rice product prepared in the liquefaction process of the present invention is a thin liquid with little or no viscosity.
The method for producing a container-packed food of the present invention may further include a seasoning step of seasoning the liquid rice product. The seasoning step is preferably carried out before the filling step.
By seasoning the liquid rice product, the seasoning can be applied more uniformly and without lumps, compared to when seasoning a gelled rice product, which will be described later.
The seasoning can be carried out by a conventional method, for example, by adding seasonings such as salt, soy sauce, sugar, etc.

(3) Filling Step The manufacturing method for containerized processed rice food of the present invention includes a filling step of filling the liquid processed rice product into a container and sealing the container.
According to the manufacturing method of the present invention, since the liquid rice product is filled into the container, there is almost no adhesion of the rice product to the manufacturing machine and tools, which may occur when filling the container with the gelled rice product, and it is possible to reduce material loss. In addition, since there is no need to manually scrape off the gelled rice product to reduce material loss, and there is no need for a manufacturing machine for this purpose, it is possible to reduce manufacturing costs.

The container used in the present invention is preferably a container that can be sealed after being filled with the liquid rice product, and more preferably a container that can be heat-sealed. In addition, the filling step in the present invention is preferably a container that is heat-sealed after being filled with the liquid rice product. An example of such a container is a container for retort food. Specifically, a retort pouch can be used.
By using a sealable container, particularly a heat-sealable container, it is possible to achieve both gelation of the liquid rice product and heat sterilization (retort heating) in the heating step described below. After heating, the containerized rice processed food can be distributed without further processing after cooling.

The liquid rice product can be filled using standard methods. For small-scale production, the filling can be done by hand, while for medium- to large-scale production, a general liquid filling machine can be used.

The filling step is preferably a step of vacuum-filling the liquid rice product.
Vacuum packing helps prevent deterioration of processed rice products.

Vacuum filling can be carried out by conventional methods, for example by filling a container with liquid rice processed product, reducing the pressure using a vacuum packaging machine or the like, and sealing the open part of the container to make it airtight. Alternatively, a vacuum filling machine may be used to create a vacuum inside the container, after which the liquid processed product is filled and the open part of the container is sealed.

(4) Heating Step The method for producing a packaged rice processed food of the present invention includes a heating step in which the liquid processed product packed in the container is retort-heated to gel it.
In other words, the manufacturing method of the present invention prepares a gelled rice product by heating a liquid rice product filled in a sealed container.
This structure can reduce the loss of ingredients due to the viscosity of the gelled rice product. It also eliminates the need for the labor and equipment required to reduce the loss of ingredients, and reduces production costs.

Furthermore, the heating process of the present invention not only gels the liquid rice product, but also serves the role of heat sterilization of packaged rice processed foods. In other words, the heating process of the present invention can be understood as both a gelation process for the liquid rice product and a heat sterilization process for packaged rice processed foods.

The gelled rice products of Patent Documents 1 and 2 have not been examined in terms of their subsequent storage stability or distribution, but in order to distribute these gelled rice products in a state where their storage stability is guaranteed, the produced gelled rice products must be packed into containers and further heat sterilized.
However, as mentioned above, packing gelled rice products into containers requires the effort and manufacturing costs required to reduce material loss.In addition, there are concerns about changes in the quality and physical properties of gelled rice products due to reheating.

Furthermore, the method described in Patent Document 3 has a heating and stirring section disposed inside a sealed container, and is equipped with a sealed conveying section that conveys the discharged gelatinized material to the crushing section without exposing it to the air, thereby ensuring the shelf life of the produced rice gel. The present invention does not require such special equipment, and can produce containerized rice processed foods filled with gel-like rice products using a conventional crusher, conventional heating device, etc., thereby reducing production costs.

In addition, after grains such as rice are gelatinized by heating, the starch begins to age, causing a deterioration in taste, odor, viscosity, etc. In conventional methods in which gelled rice products are produced and then packed into containers, it is believed that the ageing process advances during the work period up to packing into the container, which has a significant impact on the subsequent quality retention. On the other hand, according to the manufacturing method of the present invention, after the liquid rice product is gelled by the heating process (i.e., after gelatinization), the gelled rice product does not come into contact with air until it is opened at the time of consumption, making it possible to maintain the quality without ageing.

The heating conditions for retort heating may be as long as they are in accordance with the standards set forth in the Food Sanitation Act, and may be heating for at least 4 minutes with the temperature at the center of the food at 120°C, or heating for approximately 35 minutes with conditions that are equivalent to or more effective than this, for example, heating for approximately 35 minutes with the temperature at the center of the food at 115°C. As long as the above conditions are met, the retort heating process may be a semi-retort heating process (105-115°C), a semi-retort heating process (116-120°C), or a high-retort heating process (121°C or higher). The heating temperature is preferably 105-130°C, more preferably 110-130°C, even more preferably 110-125°C, and particularly preferably 110-120°C.

The technology of Patent Document 3 is a technology that omits heat sterilization by preventing the gelatinized material rice from coming into contact with air, but the temperature reached during the production process is 100°C (paragraphs 0016 and 0024 of Patent Document 3).
Although this temperature can kill bacteria such as Staphylococcus aureus, it is not suitable for killing spore-forming bacteria such as Bacillus cereus, and it is known that Bacillus cereus does not die even when heated at 100°C for 30 minutes.
Bacillus cereus is a soil bacterium that may widely contaminate agricultural crops such as rice, wheat, barley, etc. In order to distribute foods that can be stored at room temperature for long periods of time on the market, particularly foods that do not require cooking when eaten, it is important to sterilize them by retort heating at temperatures between 105°C and 130°C for a specified period of time.

In addition, the heating step is preferably a step of raising the core temperature of the processed rice product to 105° C. to 130° C. within 10 minutes. In other words, it is preferable that the heating step rapidly reaches the target heat sterilization temperature.
The heat sterilization temperature is more preferably 110 to 130°C, further preferably 110 to 125°C, and particularly preferably 110 to 120°C.
The time required to reach the above heat sterilization temperature is more preferably within 4 minutes, further preferably within 3 minutes, and particularly preferably within 2 minutes.
By carrying out such rapid heating, deterioration of the gelled rice product can be further suppressed.

After the heating process, the packaged rice processed food can be cooled in the usual way to obtain a packaged rice processed food that can be distributed directly to the market, including a gel-like rice product.

(5) Packaged rice processed food The present invention relates to a packaged rice processed food produced by the above-mentioned production method. The packaged rice processed food of the present invention is a food in which a gelled rice product is packed in a sealed container. The packaged rice processed food of the present invention is preferably a retort food.
The gelled rice product in the packaged rice processed food may be a mochi-like gelled rice product or a cream-like gelled rice product.

It is preferable that the packaged rice processed food is a food that does not require cooking when eaten.
The packaged rice processed food of the present invention is sufficiently sterilized as described above, and deterioration of quality is suppressed as much as possible, so that the package can be opened and eaten as is without heating at the time of eating. Note that the above characteristics do not limit the need to perform a heat treatment at the time of eating.

The packaged rice processed food of the present invention has excellent preservability and can ensure a long shelf life while maintaining its quality. Therefore, it can be used as a preserved food in times of disasters, etc.
It is noted that it is impossible or almost impractical to directly specify the above features by the structure or properties of an object.
As indicators of shelf life, for example, test items, test period, storage temperature, etc. can be set and physicochemical tests, sensory tests, and microbial tests can be performed. However, foods sterilized by retort heating have a long shelf life, 1-2 years on average, so in order to prove that they have high shelf life, that is, that their physical properties and quality do not change for a longer period compared to the prior art, it is necessary to subject them to the above tests after storing them for about 1-2 years after production, and it is also necessary to consider and examine parameters that are characteristic of the prior art. Under the first-to-file principle, it is not practical to file an application after conducting the above experiments and examinations.

<Confirmation test of filling properties of rice processed products>
In order to demonstrate the difficulty of filling a container with a gelled rice product, a comparative test was conducted between filling a container with a liquid rice product and filling a container with a gelled rice product.

First, 100 g of raw rice (non-glutinous rice) was washed in a conventional manner, and then water was added in an amount 1.2 times the weight of the raw rice, and the rice was soaked at 25° C. for 1 hour.
The water used for soaking was then discarded, and the water-added raw rice was placed in a high-performance blender (Vitamix). Three times the weight of the raw rice was added to the high-performance blender, and the rice was crushed for four minutes to obtain a liquid rice product.

A portion of the obtained liquid rice processed product was filled into a transparent zippered bag (filling with liquid rice processed product).
In addition, a portion of the liquid rice product was transferred to a frying pan and heated to gel the liquid rice product.
The resulting gel-like rice product was scraped off with a spatula or spoon and packed into a transparent zippered bag.
These steps and the results after filling are shown in Figure 1.

As shown in Figure 1, it was found that while liquid rice products can be easily filled into containers, gelled rice products tend to stick to frying pans and are difficult to recover, resulting in material waste. In addition, gelled rice products tend to stick to the containers they are filled into, making it difficult to fill them neatly.

In this test example, an example was shown in which the gelled rice product was filled by hand, but it is understood that similar problems due to the viscosity of the gelled rice product can occur even when filling using a machine.
That is, by preparing the gelled rice product before filling the container, the gelled rice product may stick to the heating container, the equipment used for the subsequent processing, piping, etc., resulting in material loss. Furthermore, the gelled rice product may clog the piping, etc., causing equipment failure. In order to reduce material loss or prevent equipment failure, a mechanism to prevent sticking to the equipment is required, which complicates the equipment and increases manufacturing costs.
Furthermore, in order to fill containers with gelled rice products, it is necessary to prepare a filling machine suitable for viscous materials.

On the other hand, according to the manufacturing method of the present invention, the gelation of the liquid rice product is carried out after filling the container, so the gelled rice product does not stick to the manufacturing equipment. In addition, since the liquid rice product is filled into the container, a general liquid filling machine can be used. Furthermore, retort heating, which is carried out after filling the container, sterilizes the product as well as gels it, so the gelled rice product does not come into contact with air and has excellent preservation properties.

<Production Example>
A liquid rice product was prepared using the same procedure as in the above-mentioned confirmation test. After filling a retort pouch with the prepared liquid rice product, the retort pouch was depressurized using a vacuum packaging machine, and the opening of the retort pouch was heat-sealed. The retort pouch filled with the liquid rice product was retort-heated using a retort heat sterilization device (manufactured by Toyo Seikan Co., Ltd.). The retort heating was performed by rapidly heating the center temperature of the rice product to 120°C, and then heating for 8 minutes. Figure 2 shows the produced containerized rice processed food (top of Figure 2) and the gelled rice product placed on a paper plate after the container was opened (bottom of Figure 2).

As shown in Figure 2, even when the liquid rice product was filled into a retort pouch and subjected to retort heating, a gelled rice product with physical properties such as viscosity equivalent to those of conventional products was obtained. The packaged rice processed food of the present invention has excellent preservability because it is subjected to retort heating.
When the gelled rice product was eaten as is without being cooked, it was confirmed that it had a mochi-like texture.

3 to 5 show application examples of the containerized processed rice food of the present invention.
Figure 3 shows an example of a mochi-like gelled rice product topped with shredded seaweed and wasabi.
FIG. 4 shows an example of a mochi-like gelatinized rice product coated with soybean flour.
The gelled rice processed product of the present invention has a mochi-like texture, can be stored at room temperature for a long period of time, and does not require cooking when consumed. When consumed together with a protein such as soybean flour, it can be used as a nutritional supplement during disasters, etc.

FIG. 5 shows an example of a creamy gel-like rice product mixed with heated vegetable powder to make a paste and spread it on bread.
By using plant-based ingredients to adjust the flavor, vegan and allergy-friendly foods can be easily prepared.

The present invention can be applied to preserved food in times of disasters, etc.

Claims (6)

A method for producing a container-packed rice processed food product in which a gelled rice product is packed, comprising:
A liquefaction process in which the hydrated raw rice is pulverized to prepare a liquid rice product;
A filling step of filling the liquid rice product into a container and sealing the container;
A heating step of retorting the liquid rice processed product filled in the container to gel it.
A manufacturing method for packaged rice processed foods. The method for producing a container-packed rice processed food according to claim 1, wherein the filling step is a step of vacuum-packing the liquid rice product into a container. The method for producing a packaged rice processed food according to claim 1, wherein the heating step is a step of performing retort heating at 105 to 130°C. The manufacturing method according to claim 1, wherein the container is a container for retort food. The manufacturing method according to claim 1, wherein the packaged rice processed food is a food that does not require cooking when eaten. A packaged rice processed food produced by the method according to any one of claims 1 to 5.