Method for producing food material

Abstract

To provide a food material suitable for use in swallowing food in which rice flour of high amylose rice is uniformly dispersed and has good fluidity, and these physical properties can be maintained even after storage.SOLUTION: The present invention provides a method for producing food material that includes a step 1) of adding, to an un-α-converted rice flour of high amylose rice, a water-based raw material of a weight of 2 to 20 folds with respect to the rice flour weight, and a step 2) of warming at 65°C or more and 79°C or less for 4 minutes or more.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a method for producing a food material, and more particularly, to a method for producing a food material having fluidity and suitable for use as a swallowable food.

Background Art

[0002] In Japan, with the progress of aging, the number of dysphagic patients who have difficulty eating and swallowing is increasing, and the demand for soft, low-adhesion, and easily swallowable foods, so-called swallowable foods, is increasing. Since the rice flour of high amylose rice exhibits a jelly-like state with low adhesion when heated after adding water, it is expected to be used as a food material for swallowing.

[0003] However, when making a jelly-like food by heating rice flour, it is preferable to heat it uniformly together with another material added as necessary. Stirring can be performed for homogenization and mixing with another material, but labor and equipment for stirring are required. Therefore, the development of means for uniformly dispersing rice flour in water is required.

[0004] Patent Document 1 describes that a gel food material can be prepared by high-speed shearing of cooked rice of high amylose rice. Patent Document 2 describes pregelatinized rice flour having an amylose content in the range of 20 to 30% and a degree of gelatinization in the range of 60 to 95%. The method described in Patent Document 3 is a method for producing a food that imparts thickening or gelling properties by adding low-temperature hot water using high amylose rice as a material. Non-Patent Documents 1 and 2 describe that a gel prepared by adding water to rice flour of high amylose rice and heating at a high temperature of 90 to 100°C exhibits physical properties suitable for foods for dysphagic patients and can be stored refrigerated.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

[0006] [Non-Patent Document 1] Ashida et al., Physical properties of gels prepared from high-amylose rice flour (2019) Journal of the Japanese Society of Food Science and Technology 66(8), 290-298 (published August 15, 2019) [Non-patent document 2] Ashida et al., Properties of gel obtained from rice flour of high amylose rice "Kita Mizuho" (2015) 62nd Annual Meeting of the Japanese Society for Food Science and Technology Summary of the Invention [Problem to be solved by the invention]

[0007] However, Patent Documents 1 and 3 are directed to rice, not rice flour. Pregelatinized rice flour, as in Patent Document 2, becomes viscous when water is added, and therefore requires some kind of dispersion treatment, such as stirring, at the time of adding water in order to disperse it in water. Furthermore, pregelatinized rice flour is expensive because it is made by pregelatinizing raw rice, and is difficult to obtain at low cost. Non-Patent Documents 1 and 2 have the problem of requiring constant stirring and heating to uniformly disperse the rice flour.

[0008] The present invention aims to provide a food material suitable for use in dysphagia foods, in which rice flour from high-amylose rice is uniformly dispersed, has good fluidity, and can retain these physical properties even after storage. [Means for solving the problem]

[0009] The present invention provides the following [1] to [7]. [1] Step 1) Adding an aqueous raw material to pregelatinized rice flour of high-amylose rice in an amount of 2 to 20 times the weight of the rice flour; Step 2) Heat at 65°C to 79°C for at least 4 minutes. A method for producing a food material, comprising: 〔2〕The method according to 〔1〕, wherein the high amylose rice is a high amylose rice with high alkali disintegration property, and the heating temperature in step 2 is 65°C or higher and 75°C or lower. 〔3〕The method according to 〔1〕, wherein the high amylose rice is a high amylose rice with low alkali disintegration property, and the heating temperature in step 2 is 73°C or higher and 79°C or lower. 〔4〕Step 3) Freezing The method according to any one of 〔1〕 to 〔3〕, further comprising 〔5〕The method according to 〔4〕, wherein the food material is a frozen food material. 〔6〕A method for producing a food, comprising heating a food raw material containing a food material obtained by the method according to any one of 〔1〕 to 〔5〕 at a gelatinization temperature or higher. 〔7〕The method according to 〔6〕, wherein the food is a retort pouch food.

Advantages of the Invention

[0010] According to the present invention, it becomes possible to produce and provide a food material derived from a uniform and fluid rice flour of high amylose rice.

Brief Description of the Drawings

[0011]

Figure 1

Figure 2

Embodiments for Carrying Out the Invention

[0012] 〔Method for Producing Food Material〕 This method includes the following steps 1 and 2, and usually, steps 1 and 2 are performed in this order. It may further include step 3, and in that case, usually, step 3 is performed after step 2.

[0013] (Step 1: Water Addition Step) In step 1, water is added to the rice flour of high amylose rice.

[0014] -High amylose rice- The rice flour used in Step 1 is rice flour made from high amylose rice. In this specification, high amylose rice refers to high amylose rice with an apparent amylose content of 24% or more. The upper limit of the amylose content is not particularly limited and may exceed 30%. The apparent amylose content can be determined by the iodine colorimetric method.

[0015] High amylose rice usually has a Wxa type of waxy gene (the gene encoding starch granule-bound starch synthase I that synthesizes amylose), but there are also varieties with a Wxb type that show a high amylose content of about 25%, and these are also included in the amylose rice in this specification. Domestic high amylose rice varieties include "Hokuzuiho" (mainly for Hokkaido); "Asia no Kaori", "Koshi no Kaori", "Amichan Mai", "Yume Juisai" (mainly for eastern Japan); "Fukunoko", "Mizuho Chikara" (for western Japan), etc., but are not limited to these, and various foreign high amylose rice varieties may also be used. Also, high amylose rice can be any of Japonica, Indica, and Javanica (Japonica) varieties.

[0016] High-amylose rice is available in varieties that are alkaline-degradable and those that are alkaline-resistant. Alkaline degradability is controlled by two natural mutations in the alk locus (starch synthase IIa gene, SSIIa) on chromosome 6 of rice. Four single nucleotide polymorphisms (SNPs) associated with amino acid substitutions have been identified within the SSIIa gene. A G-to-A change in SNP3, located at nucleotide position 2209 from the translation start site of the SSIIa gene, or a C-to-T change in SNP4, located at nucleotide position 2341, results in alkaline degradability, accompanied by an increase in the proportion of short-chain amylopectin and a decrease in the starch gelatinization temperature (references: NARO 2005 Research Results Information https: / / www.naro.go.jp / project / results / laboratory / nics / 2005 / nics05-07.html, Umemoto and Aoki (2005) Funct. Plant Biol. 32: 763-768). Alkali disintegration can be determined by the presence or absence of starch elution after soaking rice grains in an alkaline solution for several hours. For example, if broken pieces of brown rice are soaked in a 1.5% aqueous potassium hydroxide solution and allowed to stand at room temperature, if starch elution from the grains is observed, the rice is evaluated as being easily alkaline disintegrable, and if no starch elution is observed, the rice is evaluated as being difficult to disintegrate in alkaline. Among high-amylose rice varieties, examples of easily alkaline disintegrable varieties include "Fukunoko," "Kita Mizuho," "Amichanmai," "Yumejuiro," "Mizuho Chikara," "Hoshinishiki," "Hoshiyutaka," and "Echi no Risotto," while examples of difficult alkaline disintegrable varieties include "Ajia no Kaori" and "Echi no Kaori."

[0017] -Non-gelatinized rice flour- In this specification, non-gelatinized rice flour refers to rice flour other than pregelatinized (gelatinized) rice flour. Examples of non-gelatinized rice flour include joshinko (high-grade rice flour), shinko (new-grade rice flour), nainshinko (normal-grade rice flour), and joyoko (high-grade rice flour). The particle size of the rice flour is not particularly limited. Non-gelatinized rice flour from high-amylose rice may be a single type, or a combination of two or more types that differ in high-amylose rice variety, harvest year, cultivation method, rice flour manufacturing method, and physical properties (e.g., particle size).

[0018] -Aqueous raw materials- Examples of the aqueous raw materials include water. The water may be tap water, natural water, mineral water, purified water (e.g., ion-exchanged water, distilled water), or any other water used for food. The aqueous raw materials other than water may be liquid foods or food ingredients, and examples include milk, soy milk, fruit juice, milk beverages, tea, coffee, dashi, soup, and their aqueous solutions.

[0019] -Water addition amount- The water addition amount is 2 times or more, preferably 3 times or more, based on the weight of the rice flour. Thereby, a uniform slurry can be obtained. The upper limit is not particularly limited, but is usually 20 times or less, preferably 15 times or less, more preferably 12 times or less. Therefore, the water addition amount is usually 2 to 20 times, preferably 2 to 15 times, more preferably 3 to 12 times. When making a concentrated food material (e.g., a food material that is added with water before use), the water addition amount is preferably 5 times or less, more preferably less than 5 times, still more preferably 4.5 times or less.

[0020] Before adding water or before heating (step 2) after adding water, stirring (e.g., manual stirring, mechanical stirring) may be performed in advance.

[0021] (Step 2: Heating step) In step 2, the composition of the rice flour and water obtained in step 1 is heated. By passing through the heating step, viscosity can be imparted to the composition, sedimentation can be suppressed, and a water slurry having fluidity can be obtained. Furthermore, it can be stored frozen. The conditions for the heat treatment can be appropriately determined according to the high amylose rice (e.g., variety, cultivation method) which is the raw material of the rice flour, and an example is as follows.

[0022] -Temperature- The temperature during the heating treatment is usually 65°C or higher, preferably 67°C or higher, and more preferably 73°C or higher. This allows the rice flour to be stably dispersed in water and the viscosity to be sufficiently increased. The upper limit is usually 79°C or lower, preferably 78°C or lower, 76°C or lower, and more preferably 75°C or lower. This suppresses gelatinization of the starch in the rice flour and prevents retrogradation (e.g., an increase in viscosity) after heating. Therefore, the temperature for the heating treatment is 65°C or higher and 79°C or lower, preferably 67°C or higher and 78°C or lower, more preferably 73°C or higher and 76°C or lower, and even more preferably 73°C or higher and 75°C or lower. This prevents complete gelatinization, suppresses retrogradation, maintains a stable viscosity, and allows for the production of a stable rice flour water slurry that maintains its physical properties even after freezing and thawing.

[0023] In the case of varieties that are easily degraded by alkali, the temperature during the heating treatment is usually 65° C. or higher, preferably 67° C. or higher. The upper limit is usually 75° C. or lower, preferably 73° C. or lower. Therefore, the temperature is preferably 65 to 75° C., preferably 67 to 73° C.

[0024] The amylopectin chain length of the hardly alkali-disintegrable variety tends to be relatively long, leading to a high gelatinization onset temperature. Therefore, the heating temperature is preferably set higher than when using an easily alkali-disintegrable variety. That is, the lower limit of the temperature is preferably 73°C or higher, more preferably 74°C or higher, and even more preferably 75°C or higher. This can suppress the occurrence of precipitation and also suppress unevenness after subsequent hot water bathing or retort treatment. The upper limit is usually 79°C or lower, preferably 78°C or lower, more preferably 77°C or lower, and even more preferably 76°C or lower. This allows for a good slurry to be obtained, and subsequent gel formation is also favorable. Therefore, the heating temperature is 73°C or higher and 79°C or lower, preferably 74°C or higher and 78°C or lower, more preferably 75°C or higher and 76°C or lower.

[0025] -Heating time- The heating time is usually 4 minutes or more, preferably 6 minutes or more, and more preferably 8 minutes or more, with no particular upper limit, provided that it is usually 15 minutes or less.

[0026] - Method of heating - The method of heating is not particularly limited. For example, a method of directly heating the composition obtained in Step 1 using a thermostatic bath, a pot, an electromagnetic cooker (e.g., a microwave oven), etc., or a method of previously placing the composition in a small container or a bag (e.g., a pouch bag) and soaking it in hot water can be mentioned. The latter is preferred because of good workability. The heating treatment may be performed while stirring the composition (e.g., stirring by hand or by a machine).

[0027] After the heating is completed, it is usually cooled to room temperature (e.g., about 20 °C (15 - 25 °C)). The composition obtained by cooling can be in a slurry state and can be suitably used as a food material for swallowable food. Since uniform physical properties are required for swallowable food, when preparing swallowable food using rice flour of high amylose rice, usually, it is stirred by hand or by a machine during heating, or placed in a bag, heated, and the bag is kneaded before cooling to make it uniform.

[0028] (Step 3: Freezing step) In Step 3, the aqueous dispersion of rice flour obtained in Step 2 is frozen. The rice flour water slurry obtained through Step 2 can stably maintain its viscosity, and even after thawing after freezing, water separation is less likely to occur, and deterioration such as becoming spongy is suppressed, and the quality can be maintained. Therefore, through Step 3, long-term storage (e.g., for more than half a year in a frozen state) is possible. The temperature of the freezing treatment is usually -18 °C or lower. The time of the freezing treatment may be longer than the time until the aqueous dispersion becomes solid.

[0029] (Other raw materials other than rice flour and water) Ingredients other than rice flour and aqueous ingredients may be used to flavor food ingredients, improve shelf life, etc. Examples include salt, pepper, oils and fats, animal cream (fresh cream, whipped cream, etc.), skim milk, vegetable cream (e.g., soy milk, coconut, almond, and other bean) vegetable protein (beans, etc.), vegetable starch (corn starch, tapioca starch, etc.), grains, vegetables, fruits, eggs, cocoa, fruit juice (lemon juice, etc.), protein (meat, fish, processed products thereof, soybean and other vegetable processed products), alcohol, flavorings, spices, sweeteners (sugar, granulated sugar, honey, etc.), soy milk, additives (acidulants, colorings, preservatives, leavening agents (foaming agents), etc.), and combinations of two or more selected from these.

[0030] Other ingredients may be added to the system at any stage of steps 1 and 2. For example, they may be added to the rice flour, added before the heating treatment, added during the heating treatment, added after the heating treatment (before cooling), or a combination of two or more of these. After addition, stirring may be performed as needed.

[0031] (Food ingredients with fluidity) A food material is obtained through the above steps 1 and 2, and step 3, which is performed as needed. The food material is a stable, viscous slurry of rice flour that remains ungelatinized. By undergoing step 3, the food material has excellent shelf life as a frozen food material, and maintains its pre-frozen physical properties even when returned to room temperature. Therefore, it can be eaten as a food (dysphagia food) as is by heating it to the gelatinization temperature when desired. Furthermore, the flavor and / or physical properties of the resulting food can be improved by heating it to the gelatinization temperature or higher and then adding it to other food materials, or by adding it to other ingredients and then heating it to the gelatinization temperature or higher.

[0032] [Food manufacturing method] The above-mentioned food materials can be used as foods (e.g., retort pouch foods) by additionally heating them to the gelatinization temperature or higher, either directly or, if necessary, together with other ingredients. This is expected to simplify the cooking process and improve the flavor and physical properties of the food. The gelatinization temperature is usually 80°C or higher. When other ingredients are used, the timing of heating is not particularly limited; the food materials may be heated before being added to the other ingredients and then added to the other ingredients, or may be mixed with at least a portion of the other ingredients and then heated. In addition to the above-mentioned examples of other ingredients, other ingredients include cereals (e.g., rice, wheat, buckwheat, barley), eggs, dairy products (e.g., cheese, butter), and aqueous ingredients (as exemplified above). Examples of foods obtained from food materials include jellies, breads, noodles, rice cakes, baked confectioneries, creams, pizza, okonomiyaki, etc. [Example]

[0033] Example 1 and Comparative Examples 1 and 2 (Investigation of Heating Temperature) 2.5 g of rice flour from high-amylose rice "Kita Mizuho" (apparent amylose content: 30%) was added to 25 mL of water, 10 times the weight of the rice flour, and stirred. A paddle-type stirring blade was then placed in an aluminum measuring container, and the mixture was heated to 60°C (Comparative Example 1), 70°C (Example 1), or 80°C (Comparative Example 2) while stirring. The viscosity (resistance during rotation: cP) during and after heating was measured using a Rapid Visco Analyzer (RVA, Perten). The viscosity of the sample heated to 60°C barely increased, reaching a level comparable to that of Worcestershire sauce; the sample heated to 70°C had a viscosity slightly thinner than that of a medium-thick sauce; and the sample heated to 80°C had a viscosity similar to that of a thick pork cutlet sauce (Table 1).

[0034] The measuring container containing each heated sample was removed from the viscosity measuring device, left to stand overnight at 20 °C to return to room temperature, and the next day the device was set to 20 °C and the viscosity was measured in the same manner. In the 60 °C heated sample, the rice flour had completely settled, in the 70 °C heated sample, the rice flour was dispersed, and in the 80 °C heated sample, it was in a smooth paste state. When the viscosity was measured at 20 °C, the viscosity of the samples heated at 60 °C or 70 °C hardly changed compared to immediately after heating, while the viscosity of the sample heated at 80 °C increased significantly and aging was observed (Table 1).

[0035]

Table 1

[0036] Example 2 and Comparative Example 3 (Effect of heat treatment) 50 ml of water was added to 5.0 g of the same rice flour used in Example 1, placed in a pouch bag, stirred, then placed in a 70 °C constant temperature water bath and heated for 10 minutes, and then left at room temperature to observe the presence or absence of precipitation (Example 2). In the sample (Comparative Example 3) that was the same except for not being heated, precipitation occurred when left at 20 °C for 10 minutes (left in Figure 1), while the 70 °C heated sample did not precipitate even after standing overnight (right in Figure 1).

[0037] Example 3 (Effect of heat treatment) 5 g of the same rice flour used in Example 1 was added with 10 times the amount (50 mL) of water, placed in a pouch bag, shaken and stirred, and then the sample after simmering at 70 °C for 10 minutes was put into a -30 °C freezer and stored frozen for 4 days, then taken out and thawed at 20 °C. The thawed sample did not show water separation or spongification and returned to the original slurry state.

[0038] Examples 4 to 6 (Examination of water addition amount) The same rice flour used in Example 1 was added with 2 times the amount of water (Example 4: 25 g of rice flour + 50 mL of water), 3 times the amount of water (Example 5: 15 g of rice flour + 45 mL of water), and 5 times the amount of water (Example 6: 10 g of rice flour + 50 mL of water) based on the weight of the rice flour, put into a pouch bag, shaken and stirred, and then heated at 70 °C for 10 minutes (simmered). The 2-fold water-added sample was a bit firm, but the powder and water could just be mixed to form a uniform slurry. The 3-fold and 5-fold water-added samples had no problem with hardness and formed a uniform slurry state.

[0039] Example 7 (Preparation of rice jelly) To 5.0 g of the same rice flour used in Example 1, 10 times the weight (50 mL) of water was added, put into a pouch bag, shaken and stirred, and then heated at 70 °C (simmered). As a result, a viscous material was obtained. Subsequently, it was gelatinized by simmering in boiling water at 100 °C for 10 minutes and then cooled (after removing rough heat at room temperature and then refrigerated (4 °C)). A uniform jelly-like gel (rice jelly) could be prepared (Figure 2).

[0040] Examples 8 to 20 and Comparative Examples 4 to 10 (Examination of the variety of high amylose rice as raw material) To 2.5 g of each of rice flour from the high-amylose rice "Fukunoko" (apparent amylose content: 27%), the same rice flour as in Example 1, and rice flour from the high-amylose rice "Asia no Kaori" (apparent amylose content: 28%), 10 times the weight of water (25 mL) was added and stirred. A paddle-type stirring blade was then placed in an aluminum measuring container, and while stirring, "Fukunoko" and "Kita Mizuho" were heated to 60°C (Comparative Examples 4 and 6), 65°C (Examples 8 and 11), 70°C (Examples 9 and 12), 75°C (Examples 10 and 12), or 80°C (Comparative Examples 5 and 7), and heated for a total of 10 minutes. "Asia no Kaori" was heated to 60°C (Comparative Example 8), 70°C (Comparative Example 9), 73°C (Example 14), 74°C (Example 15), 75°C (Example 16), 76°C (Example 17), 77°C (Example 18), 78°C (Example 19), 79°C (Example 20), or 80°C (Comparative Example 10), and heated for a total of 10 minutes. The viscosity (rotational resistance: cP) immediately after heating and after leaving the mixture at 20°C after heating was measured using a Rapid Viscoanalyzer (RVA, Perten), and the state was observed visually.

[0041] [Table 2]

[0042] As a result, in Comparative Examples 4 to 10, where the heating temperatures were 60°C and 80°C, precipitation or retrogradation (gelatinization) occurred, whereas in Examples 8 to 20, where the heating temperatures were 65°C to 79°C or less, the viscosity did not increase too much immediately after heating or after leaving at room temperature, and either a slurry state was formed or only a small amount of precipitation occurred. Furthermore, in Examples 8 to 13, which used "Fukunoko" and "Kita Mizuho," which are easily decomposed by alkali, a slurry was maintained even under relatively low heating conditions, while in Examples 14 to 20, which used "Ajia no Kaori," which is less easily decomposed by alkali, an increase in viscosity was suppressed even under relatively high heating conditions (Table 2).

[0043] The results of these examples demonstrate that the production method of the present invention makes it possible to efficiently produce a food material that is uniform and has good fluidity from rice flour of high-amylose rice.

Claims

1. Step 1): adding an aqueous raw material in an amount of 2 to 20 times the weight of the raw rice flour of highly amylose rice with easy alkali disintegration property to the raw rice flour, and Step 2): heating at 65°C or higher and 75°C or lower for 4 minutes or more, which comprises The highly amylose rice with easy alkali disintegration property is a highly amylose rice with an apparent amylose content of 24% or more, in which when brown rice cut in a 1.5% potassium hydroxide aqueous solution is immersed and left standing at room temperature, elution of starch from the grains is observed. A method for producing a food material.

2. Step 1): adding an aqueous raw material in an amount of 2 to 20 times the weight of the raw rice flour of highly amylose rice with difficult alkali disintegration property to the raw rice flour, and Step 2): heating at 73°C or higher and 79°C or lower for 4 minutes or more, which comprises The highly amylose rice with difficult alkali disintegration property is a highly amylose rice with an apparent amylose content of 24% or more, in which when brown rice cut in a 1.5% potassium hydroxide aqueous solution is immersed and left standing at room temperature, no elution of starch from the grains is observed. A method for producing a food material.

3. Step 3): further comprising freezing The method according to claim 1 or 2.

4. The method according to claim 3, wherein the food material is a frozen food material.

5. A method for producing a food, which comprises heating a food raw material containing a food material obtained by the method according to any one of claims 1 to 4 at an α - gelatinization temperature or higher.

6. The method according to claim 5, wherein the food is a retort pouch food.

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