JP7815564B2 - Rice-like food with added nutritional ingredients - Google Patents

Description

The present invention relates to a rice grain food product containing added nutritional ingredients and a method for producing the same.

Today, rice-based foods such as polished rice and pregelatinized rice, which contain added nutrients such as vitamins and minerals, are being developed and sold, and are gaining popularity as they allow people to easily consume nutrients that are often lacking in their diet along with rice, which is a staple food.

For example, Patent Document 1 describes pregelatinized rice, which is made by attaching powdered nutritional ingredients such as vitamins to the surface of steamed rice grains, and then coating the surface of the rice grains with gelatin and drying them.

Patent documents 2-4 describe gelatinized rice, which is made by heating hydrated raw rice with microwave irradiation, impregnating the rice grains with nutrients, and then drying the rice.

Patent documents 5-7 describe artificial rice made by heating a mixture of powdered artificial rice ingredients and nutritional ingredients, then molding and drying it.

Patent documents 8-10 describe enriched polished rice in which nutritional components are incorporated into or attached to polished rice grains, which are then coated with oils and fats that do not melt at room temperature but melt when heated, and then further coated with a coating agent whose main ingredient is starch.

Japanese Patent Application Laid-Open No. 2007-29049 Japanese Patent Application Laid-Open No. 2004-41056 Japanese Patent Application Laid-Open No. 2005-192481 Japanese Patent Application Laid-Open No. 2005-40074 Japanese Unexamined Patent Publication No. 58-5148 JP 2012-120537 A Special Publication No. 2012-500014 Japanese Unexamined Patent Publication No. 58-13356 Japanese Patent Application Laid-Open No. 2003-245050 Japanese Patent Application Laid-Open No. 2003-245049

However, in conventional rice grain foods with added nutritional ingredients, the amount of added nutritional ingredients varies between rice grains, and when eating the rice grain food, the desired amount of nutritional ingredients may not be fully ingested. Furthermore, in conventional rice grain foods with added nutritional ingredients, the rice grains may be broken, damaged, stuck together, or clumped, which not only makes the food look unattractive, but can also make it difficult to handle during the manufacturing process and cause variations in the amount of added nutritional ingredients.

The present invention aims to provide a rice grain food product with added nutritional components, which has consistent amounts of added nutritional components among rice grains and has a good appearance and shape with minimal crushing, breakage, sticking, or clumping of rice grains.

As a result of extensive research aimed at solving the above-mentioned problems, the inventors discovered that by coating dried pregelatinized rice or other rice grain-like foods with fats and oils, nutritional components, and polysaccharides such as starch, it is possible to obtain rice grain-like foods with little variation in the amount of added nutritional components between rice grains and with rice grains that have a good appearance and shape.

The present invention is based on these new findings and includes the following inventions.
[1] A method for producing a rice grain food to which nutritional components have been added, comprising a step of coating dried rice grain food with oil and nutritional components.
[2] The method of [1], which comprises a step of coating the dried rice grain food with oil and fat, and then with nutritional ingredients.
[3] The method according to [1] or [2], wherein the rice grain food is pregelatinized rice, or artificial rice containing pregelatinized starch, ground pregelatinized rice, or konjac.
[4] The method according to any one of [1] to [3], wherein the oil or fat comprises one or more oils or fats selected from the group consisting of hardened vegetable oils or animal fats, waxes, and high-melting-point fatty acids.
[5] The method according to any one of [1] to [4], wherein the nutritional components include one or more components selected from the group consisting of vitamins, amino acids, minerals, dietary fiber, fatty acids, lecithin, coenzyme Q10, plant extracts, lactic acid bacteria, proteins, and enzymes.
[6] The method according to any one of [1] to [5], further comprising a step of coating a release component subsequent to the coating step.
[7] The method of [6], wherein the exfoliating component comprises one or more components selected from the group consisting of polysaccharides or components thereof, monosaccharides or sugar alcohols thereof, disaccharides or sugar alcohols thereof, and gums.
[8] A rice grain food product to which nutritional components have been added, which comprises a layer of oil and fat and nutritional components laminated on the surface of the rice grain food product.
[9] The food product of [8], in which a layer of oil and fat and a layer of nutritional components are laminated in this order from the inside to the outside on the surface of the rice grain food product.
[10] The food according to [8] or [9], wherein the rice grain food is pregelatinized rice, or artificial rice containing pregelatinized starch, ground pregelatinized rice, or konjac.
[11] The food according to any one of [8] to [10], wherein the oil or fat contains one or more oils or fats selected from the group consisting of hardened vegetable oils or animal fats, waxes, and high-melting-point fatty acids.
[12] The food according to any one of [8] to [11], wherein the nutritional components include one or more components selected from the group consisting of vitamins, amino acids, minerals, dietary fiber, fatty acids, lecithin, coenzyme Q10, plant extracts, lactic acid bacteria, proteins, and enzymes.
[13] The food product according to any one of [8] to [12], further comprising a layer of a peelable component laminated on the outside.
[14] The food product according to any one of [8] to [13], wherein the peeling component contains one or more components selected from the group consisting of polysaccharides or components thereof, monosaccharides or sugar alcohols thereof, disaccharides or sugar alcohols thereof, and gums.

The present invention makes it possible to provide a rice grain-shaped food product with added nutritional components, in which the amount of added nutritional components does not vary between grains and the rice grains have a good appearance and shape.

FIG. 1 shows photographs of gelatinized rice to which nutritional components have been added in Example 1 and Comparative Examples 1 to 4.

I. Method for Producing Rice Grain Food with Added Nutritional Ingredients The present invention relates to a method for producing a rice grain food with added nutritional ingredients. The method of the present invention comprises a step of coating a dried rice grain food with oil or fat and nutritional ingredients.

In the present invention, "rice grain food" refers to pregelatinized rice, or artificial rice containing pregelatinized starch, ground pregelatinized rice, konjac (powder), soybean (powder), etc., molded into the shape of rice grains, with pregelatinized rice being preferred.

In the present invention, "gelatinized rice" refers to grains that have been converted from starch (β-starch) to α-starch by cooking, steaming, or other methods of adding water and heating (also referred to as "gelatinization" or "gelatinization"), and then the gelatinization/gelatinization is fixed by drying. Here, "grain" is not limited to rice but refers to the seeds of grass plants, including wheat, foxtail millet, buckwheat, barnyard millet, millet, corn, and beans. In the present invention, "gelatinized rice" is not limited to rice, but is preferably rice. There are no particular limitations on the type or variety of rice, and examples include non-glutinous rice (including low-amylose rice), glutinous rice, fragrant rice, red rice, black rice, green rice, indica rice (Thai rice), and sake rice. The rice may be in the form of polished rice, brown rice, polished rice with germ, or brown rice with germ.

Drying of grains after gelatinization/gelatinization can be carried out using conventional drying methods known in the art, such as hot air drying, vacuum drying, freeze drying, drum drying, roller drying, and sun drying. Drying can be carried out at a temperature of 60-160°C, for example 120-160°C, for approximately 1-2 hours. It is preferable to dry the gelatinized rice until the moisture content after processing is approximately 1-15% by weight, preferably 1-10% by weight, and more preferably 1-5% by weight.

In the present invention, "rice grain food to which nutritional components have been added" means a rice grain food to which "nutritional components" described in detail below have been added or supplemented.
Each step will be described below.

1. Step of Coating Dried Rice Grain Food with Oils and Nutrient Components In the present invention, the "rice grain food" that serves as the core is one that has been subjected to a drying process. The "dried rice grain food" may have a moisture content of approximately 1 to 15% by weight, preferably approximately 1 to 10% by weight, and more preferably approximately 1 to 5% by weight. By using a dried rice grain food as the core, it is possible to prevent or suppress crushing, breakage, adhesion, clumping, and unevenness or peeling of the nutritional component coating of the grains (hereinafter sometimes referred to as "rice grains," but this does not mean only "rice" as described above) in the final product.

In the present invention, the "dried rice grain food" may be one produced in accordance with a conventionally known method, or a commercially available product may be used.

In the present invention, "oils and fats" preferably refer to those that do not melt at room temperature but melt when heated (for example, those with a melting point of about 35°C or higher (e.g., 40°C to 80°C)). Examples of such oils and fats include vegetable oils (e.g., canola oil, rapeseed oil, soybean oil, corn oil, cottonseed oil, peanut oil, sesame oil, rice oil, rice bran oil, camellia oil, safflower oil, olive oil, linseed oil, perilla oil, perilla oil, sunflower oil, palm oil, tea oil, coconut oil, avocado oil, kukui nut oil, grapeseed oil, cocoa butter, coconut oil, wheat germ oil, almond oil, evening primrose oil, castor oil, hazelnut oil, macadamia nut oil, rosehip oil, grape oil, cacao oil, jojoba oil, palm kernel oil, and umbellata oil). Examples of suitable oils and fats include hydrogenated oils and fats such as animal fats (e.g., beef tallow, lard, whale oil), hydrogenated oils and fats, fractionated oils and fats, and interesterified oils and fats; waxes (e.g., candelilla wax, rice wax, carnauba wax, beeswax, sugarcane wax, paraffin wax, lanolin, squalene, squalane, microcrystalline wax, ceresin, ozokenite, etc.); and high-melting-point fatty acids having approximately 14 to 28 carbon atoms, such as palmitic acid, stearic acid, behenic acid, and myristic acid, but are not limited to these. Any of the oils and fats may be used alone, or different oils and fats may be used in combination.

Dried rice grain foods can be coated with oil using a commonly used coating device. The oil is heated to a molten state, then sprayed and stirred onto the dried rice grain foods, and then dried. The amount of oil used for coating is not particularly limited, but is generally about 1% by weight or more, about 2% by weight or more, preferably about 3% by weight or more, and more preferably about 4% by weight or more, based on the amount of dried rice grain foods used as cores. Furthermore, since too much oil can impair the flavor of the rice grain foods, it is preferable to use an amount of about 15% by weight or less, for example, about 10% by weight or less, or about 5% by weight or less. If necessary, the oil may be coated in combination with an emulsifier (e.g., sucrose fatty acid ester, glycerin fatty acid ester, sorbitan fatty acid ester, etc.) or a binder (e.g., gum arabic, xanthan gum, gelatin, locust bean gum, sodium alginate, agar, α-starch, dextrin, etc.). Here, "coating together" refers not only to mixing the components and coating them together, but also to spraying the components separately, simultaneously or sequentially, to coat them. The emulsifier and binder can be used in an amount of 0 to 10% by weight, for example, 1 to 8% by weight, or 2 to 6% by weight, based on the weight of the oil or fat.

In the present invention, the oil or fat coats 50% or more, 60% or more, 70% or more, or 80% or more, preferably 90% or more, more preferably 95% or more, even more preferably 99% or more, and particularly preferably 100% of the surface area of the dried rice grain food. By coating the dried rice grain food with oil or fat, a layer of oil or fat is formed on the surface of the food, which prevents or suppresses gelatinization of the dried rice grain food upon contact with water (e.g., a preparation liquid containing nutritional components) during the manufacturing process, and prevents or suppresses the sticking of rice grains in the rice grain food and the formation of lumps due to gelatinization. This prevents or suppresses sticking of rice grains, the formation of lumps, and uneven coating of nutritional components in the final product.

In the present invention, "nutritional components" refers to components added to or supplemented in rice granular foods, and includes, for example, vitamins (e.g., water-soluble vitamins such as vitamin _B1 , vitamin _B2 , vitamin _C1 , vitamin _B6 , folic acid, nicotinic acid, and pantothenic acid; fat-soluble vitamins such as vitamin _A1 , vitamin _D1 , and vitamin E), amino acids (e.g., lysine, valine, leucine, isoleucine, threonine, methionine, phenylalanine, tryptophan, histidine, and γ-aminobutyric acid (GABA)), minerals (e.g., zinc, calcium (more specifically, calcium gluconate, calcium ascorbate, calcium pantothenate, calcium acetate, calcium lactate, calcium L-glutamate, calcium oxide, calcium acid pyrophosphate, calcium citrate, calcium chloride, calcium stearyl lactylate, calcium stearoyl lactylate, calcium sulfate, Examples of nutritional components include, but are not limited to, calcium carbonate (e.g., calcium triphosphate, calcium dihydrogen phosphate, etc.), magnesium, iron, manganese, copper, selenium, chromium, molybdenum, etc.), dietary fiber (e.g., indigestible dextrin, polydextrose, pectin, mannan, alginic acid, inulin, cellulose, henicellulose, lignin, glucan, chitin, galactan, arabinan, etc.), fatty acids such as docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), lecithin, coenzymes such as coenzyme Q10, plant extracts, lactic acid bacteria, proteins, enzymes, etc., which may be water-soluble or poorly water-soluble. Any of the nutritional components may be used alone, or different nutritional components may be used in combination.

Nutritional ingredient coating can be carried out using commonly used coating equipment by spraying and stirring a liquid containing the nutritional ingredients, prepared by dissolving or suspending the nutritional ingredients in a liquid such as water, onto the rice granule food, followed by drying. The amount of nutritional ingredient used for coating can vary depending on factors such as the type and form of the nutritional ingredient and the desired effect. It is not particularly limited, but is, for example, about 0.1% by weight or more, e.g., about 0.5% by weight or more, about 1% by weight or more, or about 2% by weight or more, preferably about 3% by weight or more, and more preferably about 4% by weight or more, based on the amount of dried rice granule food used as the core. Furthermore, because too much nutritional ingredient can impair the flavor and appearance of the rice granule food, it is preferable to use an amount of nutritional ingredient of about 30% by weight or less, e.g., about 20% by weight or less, about 10% by weight or less, or about 5% by weight or less. If necessary, the nutritional ingredient may be coated in combination with a binder. The binders described above can be used. Here, "coated in combination" is as defined above. The binder can be used in an amount of 0 to 35% by weight, for example, 1 to 30% by weight, 2 to 20% by weight, or 3 to 15% by weight, of the prepared liquid containing the nutritional ingredients.

In the present invention, the oil and nutritional ingredients can be coated on the dried rice grain food by mixing the oil and nutritional ingredients together. The mixture of oil and nutritional ingredients can contain the emulsifiers and binders described above, if necessary.

Preferably, in the present invention, the coating of oil and nutritional components is carried out by coating a dried rice grain food with oil and then further coating the oil-coated rice grain food with nutritional components. According to this aspect, the dried rice grain food is coated with oil (a layer of oil), which prevents or suppresses gelatinization upon contact with water. Therefore, the nutritional components can be sprayed and stirred onto the food in the form of a preparation in which the nutritional components are dissolved or suspended in a liquid such as water. This allows the nutritional components to be more efficiently and evenly distributed throughout the food compared to when the nutritional components are sprayed in solid (powder, etc.) form, thereby more efficiently preventing or suppressing unevenness in the coating of nutritional components between rice grains in the final product.

3. Coating with exfoliating component In the present invention, if necessary, the rice grain food coated with the oil/fat and nutritional component may be further coated with an exfoliating component to form a layer of the exfoliating component on the surface of the food.

In the present invention, the "peeling component" covers the surface of rice grain-like foods to which nutritional components have been added, and can be used to prevent or inhibit the added nutritional components from peeling off from the food when rice grains rub against each other during the production, transportation, etc. of the food.

Exfoliating ingredients include, for example, polysaccharides or substances containing polysaccharides, monosaccharides or their sugar alcohols, disaccharides or their sugar alcohols, gums, etc. Polysaccharides or substances containing polysaccharides include starches (e.g., starches such as corn starch, potato starch, sweet potato starch, wheat starch, waxy starch, tapioca starch, kudzu starch, and potato starch; cereal flours such as wheat flour and rice flour; and starch derivatives such as water-soluble starch, modified starch, and dextrin). Examples of monosaccharides or sugar alcohols thereof include L-arabinose, D-xylose, D-2-deoxyribose, D-ribose, D- or L-galactose, D-glucose, D-mannose, D-fructose, L-sorbose, L-fucose, L-rhamnose, D-glucosamine, D-sorbitol, D-mannitol, galactitol, and erythritol. Examples of disaccharides or sugar alcohols thereof include cellobiose, gentiobiose, isomaltose, kojibiose, lactose, lactitol, laminariose, laminaribiose, maltose, melibiose, nigerose, sophorose, sucrose, palatinose, maltitol, trehalose, xylitol, palatinit, reduced maltose syrup, and reduced starch syrup. Examples of gums include gum arabic, guar gum, tragacanth gum, xanthan gum, and zein. Any of the exfoliating components may be used alone, or different exfoliating components may be used in combination.

Coating of the nutritional ingredient-coated rice granule food with the peeling component can be carried out using a commonly used coating device. A liquid containing the peeling component, prepared by dissolving or suspending the peeling component in a liquid such as water, is sprayed onto the nutritional ingredient-coated rice granule food, agitated, and then dried. The amount of peeling component used for coating is not particularly limited, but is generally about 0% by weight or more, e.g., about 1% by weight or more, about 2% by weight or more, about 3% by weight or more, or about 4% by weight or more, preferably about 5% by weight or more, based on the amount of dried rice granule food used as the core. Because too much peeling component can impair the flavor and appearance of the rice granule food, it is preferable to use an amount of about 15% by weight or less, e.g., about 10% by weight or less, about 8% by weight or less, or about 6% by weight or less. If necessary, the peeling component may be coated in combination with a binder. The binders described above can be used. Here, "coated in combination" is as defined above. The binder can be used in an amount of 0 to 30% by weight, for example, 1 to 30% by weight, 2 to 20% by weight, or 3 to 15% by weight, based on the preparation liquid containing the release component.

When a peeling component is used in the present invention, the peeling component coats 50% or more, 60% or more, 70% or more, or 80% or more, preferably 90% or more, more preferably 95% or more, even more preferably 99% or more, and particularly preferably 100% of the surface area of the rice grain food coated with the nutritional component.

4. Other Coatings In the present invention, if necessary, the rice grain food coated with the oil and nutritional components may be further coated with oil. By coating the coated nutritional components with oil, it is possible to prevent or inhibit the nutritional components from leaching into the water used for washing or rice washing and being removed together with the water when the final rice grain food is washed or rice-washed. The oil and the coating method therefor are as described above. When coating with a release component in this embodiment, the "rice grain food coated with oil and nutritional components" coated with the further oil can be coated with the release component as described above.

In addition, in the present invention, other ingredients commonly used in the production of foods and beverages may be coated as needed, such as colorants, excipients, nutrient absorption enhancers (e.g., calcium absorption enhancers), flavors, flavorings, pH adjusters, fragrances, inorganic salts, sugars/sweeteners, flavor/taste components, acidulants, preservatives, antiseptics, and antioxidants. These other ingredients can be coated together with the components of each step in one or more of the steps for coating the above-mentioned oils and fats, nutrients, and peeling components.

II. Rice Grain Food with Added Nutritional Components The present invention also relates to a rice grain food with added nutritional components. The present invention comprises a rice grain food having a layer of oil and a layer of nutritional components laminated on the surface of the rice grain food. Preferably, the present invention comprises a rice grain food as a core, and a layer of oil and a layer of nutritional components laminated in this order on the surface from the inside to the outside.

If necessary, the present invention may further include a layer of exfoliating ingredients laminated on the outside of the layer of oils, fats, and nutritional ingredients.

If necessary, the present invention may also include an additional layer of fat or oil layered on the outside of the layer of fat or oil and nutritional ingredients. In this embodiment, if an exfoliating component layer is further included, the exfoliating component layer is included and layered on the outside of the "additional fat or oil layer."

The present invention can be produced using the method for producing rice grain foods to which the above-mentioned nutritional components have been added.

The rice grain food product to which the nutritional components of the present invention have been added can be filled into a container such as a pouch, can, tray, or cup, and provided in the form of a serving (e.g., 5g, 10g, 15g, 20g, 30g, 40g, 50g, 100g, 150g, 180g, 200g, etc.) measured out with a spoon or the like, a cup containing a serving, or individually packaged for each serving (e.g., stick packaging, pillow packaging).

The rice grain food product to which the nutritional ingredients of the present invention have been added can be eaten in the form of cooked rice or porridge by adding hot water or water. Alternatively, the rice grain food product to which the nutritional ingredients of the present invention have been added can be mixed with regular rice when cooking and eaten in the form of cooked rice or porridge. Rice can be cooked using a regular rice cooker.

The present invention will be explained in more detail below using examples, but the present invention is not limited to these examples.

1. Method for producing gelatinized rice with added nutritional components (Example 1)
The washed polished rice was heated with water according to a conventionally known general method to obtain cooked rice, which was then washed with water and dried to obtain gelatinized rice.

The resulting pregelatinized rice (3,000 g) was placed in a coating machine (Powrex Corporation, DRC-500), and the entire amount of an emulsified solution prepared by adding an emulsifier (fatty acid ester; 9 g) and hot water (130 g) to molten oil (extremely hardened rapeseed oil; 150 g) was sprayed onto the rice to coat it. Next, the entire amount of an aqueous solution (300 mL) containing nutritional ingredients (riboflavin; 0.35 g, ferric pyrophosphate; 60.0 g) and a binder (gum arabic; 6.0 g) was sprayed onto the rice to coat it. Furthermore, the entire amount of an aqueous suspension (300 mL) containing starch (corn starch; 100 g) and a binder (gum arabic; 3 g) was sprayed onto the rice to coat it, thereby preparing the pregelatinized rice with the nutritional ingredients of Example 1.

(Comparative Example 1)
A water-soluble nutrient (riboflavin; 0.02 g) was added to cooked rice (400 g) (not dried) that had been heated with water and washed with water, and the rice grain surface was coated with the nutrient by stirring for 15 seconds, followed by drying to prepare gelatinized rice to which the nutrient of Comparative Example 1 had been added.

(Comparative Example 2)
The same preparation method as in Comparative Example 1 was used to prepare gelatinized rice with added nutritional components as in Comparative Example 2, except that coating was performed by stirring for 3 minutes instead of 15 seconds.

(Comparative Example 3)
The same procedure as in the preparation method of Comparative Example 1 was used to prepare gelatinized rice to which the nutritional components of Comparative Example 3 had been added, except that a poorly water-soluble nutritional component (ferric pyrophosphate; 3.0 g) was used instead of the aqueous solution containing the water-soluble nutritional component (riboflavin).

(Comparative Example 4)
The same procedure as in the preparation method of Comparative Example 1 above was used to prepare gelatinized rice to which the nutritional components of Comparative Example 4 had been added, except that a poorly water-soluble nutritional component (ferric pyrophosphate; 3.0 g) was used instead of the aqueous solution containing the water-soluble nutritional component (riboflavin), and coating was performed by stirring for 3 minutes instead of 15 seconds.

The following evaluations were carried out using the nutritionally fortified gelatinized rice of Example 1 and Comparative Examples 1 to 4 obtained as described above.

2. Evaluation method for gelatinized rice with added nutrients (variation in nutritional content between grains of rice)
The variation in the coating of the nutritional components between grains of the produced pregelatinized rice to which the nutritional components had been added was evaluated based on the coloring resulting from the attachment of each nutritional component. Generally, areas where riboflavin has been attached are colored yellow, and areas where ferric pyrophosphate has been attached are colored yellowish-brown, so the variation in the coating of the nutritional components between grains can be evaluated using a stereomicroscope.

(Appearance and shape)
The pregelatinized rice to which each of the nutritional components had been added was evaluated for appearance and shape using a stereomicroscope based on the presence and degree of crushing, breakage, adhesion, clumping, etc. of the rice grains.

(Easy peeling of coatings containing poorly water-soluble ingredients)
The above-prepared gelatinized rice (25 g) to which each of the nutritional components of Example 1 and Comparative Examples 3 and 4 had been added was placed in a 1000 μm (16 mesh) sieve containing eight 30 g iron balls, and sieved for 1 minute while moving the sieve back and forth on a table at a speed of about once per second with a swing amplitude of about 20 cm while watching a stopwatch, etc. The sieved sample was then passed through a 30 mesh sieve, and the sieved powder was taken as the amount of coating peeling, and its proportion was calculated.

3. Results (variation in nutritional content between grains of rice and appearance/shape)
The above-prepared gelatinized rice to which each nutritional component was added (Example 1 and Comparative Examples 1 to 4) is shown in FIG.
In the case of the gelatinized rice (Example 1) in which nutritional components were added by sequentially coating dried gelatinized rice with oil, nutritional components (riboflavin, ferric pyrophosphate), and starch, coloring by the nutritional components was observed almost evenly among the rice grains, confirming that the nutritional components were evenly imparted to all the rice grains.Furthermore, it was confirmed that there was little crushing, breakage, sticking, clumping, etc. of the rice grains, and each rice grain had a good appearance and shape.

On the other hand, for pregelatinized rice (Comparative Examples 1-4), which was prepared by coating cooked rice with nutrients and then drying them, the degree of coloration due to the nutrients varied between grains of rice after 15 seconds of stirring, confirming variation in the coated nutrients for both riboflavin and ferric pyrophosphate (Comparative Examples 1 and 3).

Furthermore, when the rice was stirred for 3 minutes, the coloring due to the nutritional components was observed almost evenly among the rice grains for all nutrients, confirming that the nutritional components could be evenly imparted to all rice grains. However, many rice grains were found to be crushed, broken, stuck together, formed lumps, or had irregular shapes, and few rice grains had a good appearance or shape (Comparative Examples 2 and 4). This is thought to be due to physical damage caused by stirring the cooked rice and the resulting leakage of starch.

(Easy peeling of coatings containing poorly water-soluble ingredients)
The calculated coating peeling rates for Example 1 and Comparative Examples 3 and 4 are shown in the table below.

Compared to Example 1, it was confirmed that a large amount of the nutrient coating peeled off in Comparative Examples 3 and 4, meaning that the adhesion of the nutrient components to the rice grains was low. This indicates that poorly water-soluble nutrients have difficulty adhering to and coating moist cooked rice.

In contrast, in Example 1, not much of the nutrient coating peeled off, confirming that the nutrient adhered strongly to the rice grains. These results confirm that by using a method in which dried pregelatinized rice is sequentially coated with oil, nutrient, and starch, both water-soluble and poorly soluble ingredients can be attached to the rice grains with high adhesion.

As described above, it has been confirmed that the pregelatinized rice of the present invention, which is produced by sequentially coating dried pregelatinized rice with oil, nutritional components, and starch, has little variation in the amount of added nutritional components between grains, and has a good appearance and shape with few crushed, broken, stuck, or clumped grains.

Claims (7)

The method for producing a rice grain food to which nutritional components have been added includes the steps of spraying and stirring oil or fat onto a dried rice grain food, then drying it , and then coating it with nutritional components, wherein the coating of the nutritional components is carried out with a preparation liquid containing the nutritional components , water, and a binder , in which the nutritional components are dissolved or suspended. The method of claim 1, wherein the coating with oil or fat is carried out by spraying and stirring molten oil or fat onto the dried rice grain food product, followed by drying. The method according to claim 1 or 2, wherein the rice granule food is pregelatinized rice, or artificial rice containing pregelatinized starch, ground pregelatinized rice, or konjac. The method according to any one of claims 1 to 3, wherein the oil or fat comprises one or more oils or fats selected from the group consisting of hydrogenated vegetable oils or animal fats, waxes, and high-melting-point fatty acids. The method according to any one of claims 1 to 4, wherein the nutritional components include one or more components selected from the group consisting of vitamins, amino acids, minerals, dietary fiber, fatty acids, lecithin, coenzyme Q10, plant extracts, lactic acid bacteria, proteins, and enzymes. The method of any one of claims 1 to 5, further comprising a step of coating a release component following the coating step. The method of claim 6, wherein the exfoliating component comprises one or more components selected from the group consisting of polysaccharides or components thereof, monosaccharides or sugar alcohols thereof, disaccharides or sugar alcohols thereof, and gums.