JP6936069B2 - Cooked rice improver and method for manufacturing cooked rice or processed cooked rice - Google Patents

Description

The present invention relates to a cooked rice improver. More specifically, the present invention relates to a cooked rice improving agent containing a starch decomposition product satisfying a predetermined property as an active ingredient, and a method for producing cooked rice or a processed cooked rice food.

Processed cooked rice typified by rice balls are widely distributed in the ready-to-eat restaurant industry. Processed cooked rice is required to have looseness and workability as processing suitability, and is also required to have a flavor and appearance as a food. In the existing technology, for example, a technique of using edible fats and oils, emulsifiers, polysaccharides and the like to improve unraveling property and workability as processing suitability, flavor and texture and the like is used.

Specifically, for example, in Patent Document 1, by adding dextrin, which is a hydrolyzate of starch contained in cooked rice, to cooked rice, a liquid film is formed on the surface of cooked rice grains containing water. Since the rice grains are held and the adhesiveness between the rice grains is moderately reduced, the cooked rice is easily loosened, and when chewed, it is easy to break up in the mouth and eat easily, and the adhesion to the cooked rice processing machine is suppressed, so that the food A technique for improving workability and moldability during processing is disclosed.

In Patent Document 2, by containing a branched oligosaccharide whose branched chain is maltotriose as an active ingredient, it is used for improving cooked rice that has an excellent anti-aging effect that has not been seen in the past without changing the taste quality of cooked rice. Techniques for providing compositions are disclosed.

In Patent Document 3, a mixture of low-decomposition starch having a molecular weight of 500,000 to 5 million and dextrin having a DE value of more than 1 and 50 or less in a mass ratio of 1: 9 to 9: 1 is prepared. A technique for providing a cooked rice improving agent containing a cooked rice flavor having an effect of sustaining and / or enhancing the flavor of cooked rice is disclosed.

In Patent Document 4, the texture of cooked rice is improved by containing a sugar composition containing 25 to 55% by weight of constituent sugars having a degree of polymerization of 20 or more and 30 to 65% by weight of constituent sugars having a degree of polymerization of 2 to 10 by weight. However, a technique for providing an improving agent for cooked rice or cooked rice processed food, which can obtain a good texture and appearance immediately after cooking rice by reheating in a microwave oven or the like even when stored at room temperature or refrigerated, is disclosed. ing.

In recent years, as a consumer's taste, there is a tendency that the "graininess" of cooked rice, which has an appropriate hardness and elasticity and has a well-shaped rice grain, is required. However, there has been no technology that can fully satisfy the "graininess" of cooked rice. Especially in the case of rice balls, there is a problem that there is a molding process and it is more difficult to obtain a grainy feeling.

Japanese Unexamined Patent Publication No. 2016-167999 Japanese Unexamined Patent Publication No. 2015-181412 Japanese Unexamined Patent Publication No. 2017-7723 Japanese Unexamined Patent Publication No. 2004-135580

As mentioned above, in the field of cooked rice processed foods, various proposals have been made for cooked rice improvement technology, but the technology is still developing due to changes in consumer tastes and the preference for higher quality foods. The reality is that.

For example, when edible fats and oils are used to improve the looseness of cooked rice, there is a method of using an emulsifier in combination to disperse the edible fats and oils in water. However, in recent years, emulsifiers have tended to be shunned by so-called additive-free, natural-oriented users. Further, since some emulsifiers have a peculiar flavor, the flavor of processed foods may be deteriorated.

In addition, there is a method of using a starch decomposition product such as dextrin, but there is a problem that the loosening effect is insufficient by itself. Furthermore, there is an option to use edible oils and fats in combination with starch decomposition products such as dextrin and not to use emulsifiers. rice field.

Therefore, in the production of cooked rice or cooked rice processed food, the present invention mainly provides a technique capable of improving workability at the time of manufacturing and improving looseness and graininess of cooked rice or cooked rice processed food. The purpose.

As a result of diligent research on the manufacturing technology of cooked rice processed foods, the inventors of the present application have found that the graininess of cooked rice can be improved by using a starch decomposition product having a specific structure. Then, it was found that the use of this starch decomposition product also improves the dispersibility of the fats and oils when edible fats and oils are used at the time of production. As a result, the present invention has been completed by succeeding in improving the workability at the time of production and improving the looseness and graininess of cooked rice or cooked rice processed food.

That is, the present invention provides a cooked rice improving agent containing a starch decomposition product containing a branched sugar composed of a main chain and a branched chain satisfying the following (1) and (2) as an active ingredient.
(1) 7 ≦ x; However, x is the content (mass%) of the branched chain having a glucose polymerization degree (DP) of 8 to 9 in the starch decomposition product.
(2) 31 ≦ y ≦ 60; However, y is the content (mass%) in the starch decomposition product of the fraction having a molecular weight of 14,000 to 80,000.
In the cooked rice improving agent according to the present invention, the x may satisfy the following (1').
(1') 8 ≤ x
In the cooked rice improving agent according to the present invention, the y may satisfy the following (2').
(2') 35 ≤ y ≤ 60
In the starch decomposition product used for the cooked rice improving agent according to the present invention, at least a part of branched sugar having a branched chain having a glucose polymerization degree (DP) of 8 to 9 is included in the fraction having a molecular weight of 14,000 to 80,000. May be included.
The cooked rice improving agent according to the present invention may contain edible oils and fats.
In this case, the mass ratio of the starch decomposition product to the edible oil / fat can be set to 2: 1 to 15: 1.

The present invention also provides a method for producing cooked rice or a cooked rice processed food, which comprises a step of adding a starch decomposition product containing a branched sugar composed of a main chain and a branched chain satisfying the following (1) and (2). ..
(1) 7 ≦ x; However, x is the content (mass%) of the branched chain having a glucose polymerization degree (DP) of 8 to 9 in the starch decomposition product.
(2) 31 ≦ y ≦ 60; However, y is the content (mass%) in the starch decomposition product of the fraction having a molecular weight of 14,000 to 80,000.

According to the present invention, it is possible to improve the graininess of cooked rice or cooked rice processed foods, and to improve the dispersibility of cooked rice or fats and oils when edible fats and oils are used in the production of cooked rice or cooked rice processed foods. As a result, it is possible to improve the workability at the time of producing cooked rice or cooked rice processed food, and to improve the looseness and graininess of cooked rice or cooked rice processed food.

It is a drawing substitute photograph which shows the state of the pot before cooking rice and the state of cooked rice after cooking, which is seen from the bottom in Reference Example 2 in Experimental Example 3. It is a drawing substitute photograph which shows the state of the pot before cooking rice of Example 10 in Experimental Example 3 and the state which the cooked rice after cooking is seen from the bottom. It is a drawing substitute photograph which shows the state of the pot before cooking rice of Example 16 in Experimental Example 5, the state which the pot after cooking is seen from the top, and the state which the cooked rice after cooking is seen from the bottom. It is a drawing substitute photograph which shows the state of the pot before cooking rice, the state of the pot after cooking rice viewed from the top, and the state of the cooked rice after cooking seen from the bottom of Example 21 in Experimental Example 5.

Hereinafter, suitable embodiments for carrying out the present invention will be described. It should be noted that the embodiments described below show an example of typical embodiments of the present invention, and the scope of the present invention is not narrowly interpreted by this.

<Starch decomposition product>
First, the starch decomposition product used in the present invention will be described. The cooked rice improving agent according to the present invention contains the starch decomposition product described below as an active ingredient. Further, the method for producing cooked rice or cooked rice processed food according to the present invention is a method including a step of adding a starch decomposition product described below.

In the production of cooked rice processed food, the graininess of cooked rice or cooked rice processed food can be improved by using the starch decomposition product described below. Further, by using the starch decomposition product described below, the dispersibility of the fat and oil can be improved when the edible fat and oil is used at the time of production. As a result, it is possible to improve the workability at the time of producing cooked rice or cooked rice processed food, and to improve the looseness and graininess of cooked rice or cooked rice processed food. Further, since the starch decomposition product described below has a reduced so-called starch odor as compared with the conventional starch decomposition product, when it is used for cooked rice or processed rice food, it has an adverse effect on the flavor. rare.

The starch decomposition product used in the present invention contains a branched sugar composed of a main chain and a branched chain. The content (mass%) x of the branched chain having a glucose polymerization degree (DP) of 8 to 9 in the starch decomposition product is characterized by satisfying the following (1).
(1) 7 ≦ x

The content (% by mass) x of the branched chain having a glucose polymerization degree (DP) of 8 to 9 in the starch decomposition product is the content of the sugar chain having DP8 to 9 contained in the starch decomposition product. By treating the starch decomposition product with a debranching enzyme such as isoamylase or plulanase, the content of the sugar chain, which is DP8-9 in the state where the branched chain was cut, was measured, and the DP8 increased by the debranching enzyme treatment was measured. It can be obtained by calculating the amount of sugar chains of ~ 9.

Further, the starch decomposition product used in the present invention is characterized in that the content (mass%) y of the fraction having a molecular weight of 14,000 to 80,000 satisfies the following (2).
(2) 31 ≤ y ≤ 60

The starch decomposition product used in the present invention has a content (mass%) x in the starch decomposition product of a branched chain having a glucose polymerization degree (DP) of 8 to 9, and starch decomposition of a fraction having a molecular weight of 14,000 to 80,000. The content (% by mass) y in the product is characterized by satisfying both (1) and (2) above. As shown in Examples described later, by satisfying these two conditions at the same time, the graininess of cooked rice or cooked rice processed food can be improved. Further, by using this starch decomposition product, when edible fats and oils are used at the time of production, the dispersibility of the fats and oils can be improved. As a result, it is possible to improve the workability at the time of producing cooked rice or cooked rice processed food, and to improve the looseness and graininess of cooked rice or cooked rice processed food.

The starch decomposition product used in the present invention may satisfy the above (1) and (2), but it is preferable that the x satisfies the following (1'). When the x satisfies the following (1'), the graininess of cooked rice or cooked rice processed food and the dispersibility of the fats and oils when edible fats and oils are used at the time of production are further improved, and as a result, cooked rice or cooked rice processed foods It is possible to further improve the workability at the time of production, and further improve the looseness and graininess of cooked rice or cooked rice processed food.
(1') 8 ≤ x

Further, it is preferable that the y satisfies the following (2'). When the y satisfies the following (2'), the graininess of cooked rice or cooked rice processed food and the dispersibility of the fats and oils when edible fats and oils are used at the time of production are further improved, and as a result, cooked rice or cooked rice processed foods. It is possible to further improve the workability at the time of production, and further improve the looseness and graininess of cooked rice or cooked rice processed food.
(2') 35 ≤ y ≤ 60

In the starch decomposition product used in the present invention, even if the fraction having a molecular weight of 14,000 to 80,000 contains at least a part of branched sugar having a branched chain having a glucose polymerization degree (DP) of 8 to 9. good. That is, a part or all of the branched sugar having a branched chain having a glucose polymerization degree (DP) of 8 to 9 may be contained in the fraction having a molecular weight of 14,000 to 80,000, and the glucose polymerization degree (DP) may be contained. ) May be contained in a fraction other than the fraction having a molecular weight of 14,000 to 80,000.

Further, in the starch decomposition product used in the present invention, the content (mass%) z of the branched chain in the starch decomposition product having a glucose polymerization degree (DP) of 3 to 7 preferably satisfies the following (3).
(3) z ≦ 15

By setting the content (% by mass) of the branched chain having a glucose polymerization degree (DP) of 3 to 7 in the starch decomposition product to 15% by mass or less, the graininess of cooked rice or cooked rice processed food and edible oils and fats at the time of production can be obtained. The dispersibility of fats and oils when using is further improved, and as a result, the workability during the production of cooked rice or processed cooked rice food is further improved, and the looseness and graininess of cooked rice or processed cooked rice food are further improved. be able to.

The content (% by mass) z in the starch decomposition product of the branched chain having a glucose polymerization degree (DP) of 3 to 7 is the content (mass%) z in the starch decomposition product of the branched chain having a glucose polymerization degree (DP) of 8 to 9. Content (% by mass) x, the content of sugar chains that are DP3 to 7 contained in the starch decomposition product, and the starch decomposition product are branched by treating with a debranching enzyme such as isoamylase or pluranase. It can be obtained by measuring the content of sugar chains having DP3 to 7 in the state where the chains are cut and calculating the amount of sugar chains having DP3 to 7 increased by the debranching enzyme treatment.

<Manufacturing method of starch decomposition products>
The starch decomposition product used in the present invention has a novel composition itself, and the method for obtaining the starch decomposition product is not particularly limited. For example, the starch raw material can be obtained by appropriately combining predetermined operations such as treatment with a general acid or enzyme, various chromatographys, membrane separation, ethanol precipitation and the like.

As the starch raw material that can be used as a raw material for obtaining the starch decomposition product used in the present invention, one or more starch raw materials that can be a known raw material for the starch decomposition product can be freely selected and used. For example, starches such as cornstarch, rice starch, wheat starch (aboveground starch), and starches derived from rhizomes or roots such as potato, cassava, and sweet potato (underground starch) can be mentioned.

As a method for efficiently obtaining the starch decomposition product used in the present invention, there is a method in which a starch raw material is liquefied with an acid or α-amylase and then a branching enzyme is allowed to act on it. When liquefied with an acid, the type of acid that can be used for producing the starch decomposition product used in the present invention is not particularly limited, and if the acid is capable of acid liquefying starch, one known acid or one is used. Two or more types can be freely selected and used. For example, hydrochloric acid, oxalic acid and the like can be used.

It is also possible to freely combine treatments with other degrading enzymes (for example, α-amylase) before and after acid liquefaction of the starch raw material and before and after the action of the branching enzyme. For example, it is also possible to adopt a method in which a starch raw material is liquefied with an acid, then a branching enzyme is allowed to act on the starch raw material, and then the starch raw material is further treated with another degrading enzyme (for example, α-amylase). As described above, by allowing the decomposing enzyme to act after the action by the acid liquefaction and the branching enzyme, it becomes easy to adjust the degree of decomposition of the starch decomposition product to a desired range.

Further, in the starch decomposition product used in the present invention, the starch raw material is not acidified, but the starch raw material is liquefied using a decomposing enzyme such as α-amylase, and then treated with a branching enzyme, and then further. It can also be produced by degrading with a degrading enzyme such as α-amylase.

Here, the branching enzyme acts on a linear glucan linked by an α-1,4-glucoside bond to cleave the α-1,4-glucoside bond and α-1,6- It is a general term for enzymes that have the function of forming branches by glucosidic bonds. When a branching enzyme is used in the production of the starch decomposition product used in the present invention, the type thereof is not particularly limited, and one or more known branching enzymes can be freely selected and used. For example, those purified from animals, bacteria and the like, or those purified from plants such as potatoes, rice seeds and corn seeds can be used.

As described above, the method for producing the starch decomposition product used in the present invention is not particularly limited, but a method in which the starch raw material is liquefied with an acid or an enzyme and then subjected to a branching enzyme treatment is preferable. By using this method, the content of branched chains having a glucose polymerization degree (DP) of 8 to 9 can be easily adjusted to a desired range. Therefore, when the starch decomposition product used in the present invention is inexpensively and industrially produced. Suitable. Further, a method of performing α-amylase treatment before and after liquefaction of the starch raw material and before and after the action of the branching enzyme is preferable. By using this method, it becomes easy to adjust the degree of decomposition of the starch decomposition product to a desired range.

Further, in the present invention, it is possible to remove impurities by performing various treatments so as to obtain the desired starch decomposition product, and then performing activated carbon decolorization, ion purification and the like, and it is preferable to remove impurities.

Further, it can be used as a cooked rice improver in a powdered state by concentrating to a solid content of 30 to 80% to make it liquid, or dehydrating and drying it by vacuum drying or spray drying.

<Rice improver>
The cooked rice improving agent according to the present invention is characterized by containing the above-mentioned starch decomposition product as an active ingredient. Further, since the cooked rice improving agent according to the present invention has very little unpleasant flavor peculiar to starch decomposition products, it has almost no adverse effect on the flavor of cooked rice and cooked rice processed foods, and can be applied to various processed foods. ..

The cooked rice improving agent according to the present invention may be composed of only the above-mentioned starch decomposition product as long as it contains the above-mentioned starch decomposition product as an active ingredient, and other components as long as the effects of the present invention are not impaired. Can be freely selected and contained in one kind or two or more kinds. As other components, for example, components such as excipients, pH adjusters, colorants, flavoring agents, disintegrants, lubricants, stabilizers and emulsifiers, which are usually used for formulation, can be used. Furthermore, components having known or future functions can be used in combination as appropriate according to the purpose. Since the starch decomposition product described above is classified as a food product, the cooked rice improving agent according to the present invention can be treated as a food product depending on the selection of ingredients other than the starch decomposition product.

Further, the cooked rice improving agent according to the present invention can contain edible oils and fats. The edible fats and oils that can be used in the cooked rice improving agent according to the present invention are not particularly limited as long as they are edible fats and oils that can be used in the production of cooked rice and processed cooked rice foods, and one or more known edible fats and oils are used. , Can be freely selected and used. For example, saflower oil, sunflower oil, cottonseed oil, rapeseed oil, soybean oil, rice oil, camellia oil, corn oil, palm oil, palm kernel oil, palm oil, olive oil, sesame oil, flaxseed oil, avocado oil, coconut oil, egoma oil, Vegetable fats and oils such as chia seed oil and grape seed oil, animal fats and oils such as beef fat, fish oil, whale oil, and pork fat, ester exchange oils made from these, hardened oils, fractionated oils, medium chain fatty acid triglycerides, and powder processing of these Examples thereof include processed oils and fats such as powdered oils and fats.

When the cooked rice improving agent according to the present invention contains edible oils and fats, the blending amount thereof is not particularly limited and can be freely set as long as the effects of the present invention are not impaired. In the present invention, in particular, the mass ratio of the starch decomposition product to the edible oil / fat is preferably set to 2: 1 to 15: 1, more preferably 3: 1 to 12: 1, and 6: 1 to 10 :. 1 is even more preferable. By setting it in this range, the production of the cooked rice improving agent becomes easy, the quality is stable, and the looseness, graininess and luster of the produced cooked rice or processed cooked rice can be further improved.

Further, the cooked rice improving agent according to the present invention may contain flour, starch and processed products thereof in addition to the above-mentioned starch decomposition products. When the flour, starch and processed products thereof are contained, the type thereof is not particularly limited as long as the effect of the present invention is not impaired, and one or two or more known flours or processed products thereof are freely selected and used. be able to. For example, rice flour, corn flour, soybean flour and other flours, rice starch (eg, glutinous rice starch, glutinous rice starch, etc.), corn starch (eg, normal corn starch, waxy corn starch, high amylose corn starch, etc.), horse bell starch, tapioca starch, etc. Examples of starch and processed products made from these (eg, processed grain flour, processed starch, etc.). Among these, it is particularly preferable to use rice flour derived from rice from the viewpoint of not affecting the flavor and texture of cooked rice or processed cooked rice. Further, by using rice flour, when the cooked rice improving agent according to the present invention contains edible fats and oils, the rice flour is dispersed in water in a state where the edible fats and oils are adsorbed, so that the dispersibility of the edible fats and oils can be further improved. ..

The form of the cooked rice improving agent according to the present invention is not particularly limited as long as the effect of the present invention is not impaired, and a free form can be designed. For example, it is possible to distribute the starch decomposition product described above and any other component in a mixed state (so-called mixed product), and as a specific form, emulsification containing powder, granules, and water. Physical conditions and the like can be mentioned. Of these, the powdery or granular form is particularly preferable because it has high storage stability.

<Manufacturing method of cooked rice or processed cooked rice>
The method for producing cooked rice or cooked rice processed food according to the present invention is a method including a step of adding the above-mentioned starch decomposition product or cooked rice improving agent. In the method for producing cooked rice or cooked rice processed food according to the present invention, the method for adding the starch decomposition product or cooked rice improving agent described above is not particularly limited as long as the effect of the present invention is not impaired, and the process for producing cooked rice or cooked rice processed food. Can be added in any of the above. For example, a method of sharpening rice as necessary, immersing it in a predetermined amount of water, adding the above-mentioned starch decomposition product or cooked rice improver, stirring and dispersing the rice before or after the immersion is selected. be able to. At the time of cooking rice, it can be used in combination with other cooked rice improving agents such as edible oils and fats that can be contained in the above-mentioned cooked rice improving agent and oil for cooking rice.

Further, after cooking rice by a known method, the above-mentioned starch decomposition product or cooked rice improving agent can be added in the step of processing the cooked rice. For example, in the case of producing processed cooked rice such as fried rice, it is also possible to add the above-mentioned starch decomposition product or cooked rice improver at the time of frying the cooked rice.

Further, in the step of adding the above-mentioned starch decomposition product or cooked rice improving agent at the time of cooking rice and processing the cooked rice after cooking, the method of further adding the above-mentioned starch decomposition product or cooked rice improving agent can also be adopted.

In the method for producing cooked rice or cooked rice processed food according to the present invention, the amount of the starch decomposition product or cooked rice improving agent added can be freely set as long as the effects of the present invention are not impaired. In the present invention, it is particularly preferable to add 0.5 parts by mass or more, more preferably 1.0 part by mass or more, and 1.5 parts by mass or more as the starch decomposition product with respect to 100 parts by mass of raw rice. It is even more preferable to add it. As shown in Examples described later, by adding 0.5 parts by mass or more of the starch decomposition product, the graininess of cooked rice or cooked rice processed food can be further improved.

The upper limit of the amount of the starch decomposition product or the cooked rice improving agent added is not particularly limited, but if too much is added, the cooked rice or cooked rice processed food after production may not be sufficiently gelatinized, and the amount of water added in the production may be increased. It will be necessary to make appropriate adjustments. In consideration of cost, it is preferable to add 10.0 parts by mass or less as the starch decomposition product, more preferably 8.0 parts by mass or less, and 6.0 parts by mass or less with respect to 100 parts by mass of raw rice. Is even more preferable.

The cooked rice or cooked rice processed food that can be produced by the production method according to the present invention is not particularly limited, and any known processed cooked rice food can be produced. For example, cooked rice, rice balls, cooked rice, paella, pilaf, sushi, cooked rice, and other cooked rice that are transported, stored, and displayed at room temperature or refrigerated temperatures in convenience stores, supermarkets, department stores, etc. Be done.

Hereinafter, the present invention will be described in more detail based on Examples. It should be noted that the examples described below show an example of a typical example of the present invention, and the scope of the present invention is not narrowly interpreted by this.

(1) Test method [branch-making enzyme]
In this experimental example, an enzyme derived from Rhodothermus obamensis (hereinafter referred to as "branching enzyme") purified according to the method of WO00 / 58445 was used as an example of the branching enzyme.

The activity of the branching enzyme was measured by the following method.
As the substrate solution, an amylose solution in which 0.1% by mass of amylose (manufactured by Sigma, A0512) was dissolved in 0.1 M acetate buffer (pH 5.2) was used.
Add 50 μL of enzyme solution to 50 μL of substrate solution, react at 30 ° C. for 30 minutes, and then add 2 mL of iodine-potassium iodide solution (0.39 mM iodine-6 mM potassium iodide-3.8 mM potassium iodide mixture solution). In addition, the reaction was stopped. As a blank solution, a solution to which water was added instead of the enzyme solution was prepared. The absorbance at 660 nm was measured 15 minutes after the reaction was stopped. One unit of the enzyme activity amount of the branching enzyme was an enzyme activity amount that reduced the absorbance at 660 nm by 1% per minute when tested under the above conditions.

[DE]
It was calculated according to the Raineinon method of "Starch sugar-related industrial analysis method" (edited by the Starch Sugar Technology Subcommittee).

[Contents of fractions having a molecular weight of 14,000 to 80,000 of starch decomposition products]
The analysis was performed by gel filtration chromatography under the conditions shown in Table 1 below. Standard P-82 (manufactured by Showa Denko KK) for Shodex standard GFC (water-based GPC) columns is used as the molecular weight standard, and the decomposition product of starch is based on the calibration curve calculated from the correlation between the elution time of the molecular weight standard and the molecular weight. The content of the fraction having a molecular weight of 14,000 to 80,000 was calculated.

[Content of branched chain having DP8-9 or branched chain having DP3-7 in starch decomposition product]
a. Measurement of sugar chain content of DP8-9 or DP3-7 in untreated starch decomposition product The starch decomposition product solution adjusted to Brix 1% was analyzed by liquid chromatography under the conditions shown in Table 2 below. , The content of DP8-9 or DP3-7 was measured based on the retention time.

b. Measurement of sugar chain content of DP8-9 or DP3-7 in the debranched enzyme-treated product of starch decomposition product with branched chains 1M acetate buffer in 200 μL of starch decomposition product solution adjusted to Brix 5% 2 μL of solution (pH 5.0), isoamylase (derived from Pseudomonas sp., Made by Megazyme) 125 units per solid content (g), and plulanase (derived from Klebsiella starch, manufactured by Megazyme) 800 units per solid content (g). , The total amount was adjusted to 400 μL with water. This was enzymatically reacted at 40 ° C. for 24 hours, and then the reaction was stopped by boiling. 600 μL of water was added thereto, and centrifugation was performed at 12000 rpm for 5 minutes. After desalting and filtering 900 μL of the supernatant, analysis was performed by liquid chromatography under the conditions shown in Table 2, and the content of DP8-9 or DP3-7 was measured based on the retention time.

c. Calculation of the content of branched chains that are DP8-9 or DP3-7 in the starch decomposition product Starch decomposition by subtracting the content of DP8-9 determined in a from the content of DP8-9 determined in b above. The content of branched chains with DP8-9 in the product was calculated. Similarly, the content of the branched chain which is DP3 to 7 in the starch decomposition product was calculated by subtracting the content of DP3 to 7 obtained in the above a from the content of DP3 to 7 obtained in the above b.

[Evaluation method]
a. Grain texture (texture with moderate hardness and elasticity, and the shape of rice grains is in order)
For cooked rice or cooked rice processed foods shown in Tables 3 to 7 below, the graininess was evaluated by 10 panelists using the following evaluation criteria. The average value of the panelists' evaluation points was calculated, and the value rounded to the first decimal place was used as the evaluation point.
5: Firm graininess, very good 4: Grainy feeling, good 3: Normal 2: Almost no graininess, slightly bad 1: No graininess, bad

b. Dispersibility of fats and oils The dispersibility of fats and oils shown in Tables 5 to 7 below was evaluated by a specialized panelist based on the following evaluation criteria.
◎: Good ○: Somewhat good △: Tolerance ×: Bad

c. Workability (when molding rice balls, separate from the pot)
The workability shown in Tables 5 to 7 below (when forming rice balls and separating from the pot) was evaluated by a specialized panelist based on the following evaluation criteria.
◎: Good ○: Somewhat good △: Tolerance ×: Bad

d. Unraveling (when eating)
The cooked rice or cooked rice processed foods shown in Tables 5 to 7 below were evaluated for looseness by 10 panelists using the following evaluation criteria. The average value of the panelists' evaluation points was calculated, and the value rounded to the first decimal place was used as the evaluation point.
5: Very good 4: Good 3: Normal 2: Somewhat bad 1: Bad

e. Gloss The cooked rice or cooked rice processed foods shown in Tables 5 to 7 below were evaluated for gloss by 10 panelists using the following evaluation criteria. The average value of the panelists' evaluation points was calculated, and the value rounded to the first decimal place was used as the evaluation point.
5: Very glossy 4: Glossy 3: Normal 2: Matte and slightly aged 1: Dull and aged

(2) Production of starch decomposition product [Starch decomposition product A]
Α-amylase (Crystase T10S, manufactured by Amano Enzyme Co., Ltd.) was added in an amount of 0.2% by mass per solid content (g) to a 30% by mass cornstarch slurry adjusted to pH 5.8 with 10% by mass of slaked lime, and jetted. It was liquefied with a cooker (temperature 110 ° C.), the liquefied liquid was kept warm at 95 ° C., DE was measured over time, and when DE7 was reached, the pH was adjusted to 4.0 with 10% hydrochloric acid. The reaction was stopped by boiling. After adjusting the pH of the sugar solution in which the reaction was stopped to 6.0, 600 units of branching enzyme was added per solid content (g), and the reaction was carried out at 65 ° C. for 60 hours. Further, α-amylase (Crystase T10S, manufactured by Amano Enzyme Co., Ltd.) was added in an amount of 0.02% by mass per solid content (g), the reaction was carried out at 80 ° C., and DE was measured over time to bring DE to 10. At that time, the pH was adjusted to 4.0 with 10% hydrochloric acid, and the reaction was stopped by boiling. The solution of this starch decomposition product was decolorized with activated carbon, ion-purified, and concentrated to a solid content concentration of 50% by mass. Further, the concentrated solution was pulverized with a spray dryer to obtain a starch decomposition product A.

[Starch decomposition product B]
To 30% by mass of cornstarch slurry adjusted to pH 5.8 with 10% by mass of slaked lime, α-amylase (Spitzase HK, manufactured by Nagase ChemteX Corporation) was added in an amount of 0.2% by mass per solid content (g), and jetted. It was liquefied with a cooker (temperature 110 ° C.), the liquefied liquid was kept warm at 95 ° C., DE was measured over time, and when DE7 was reached, the pH was adjusted to 4.0 with 10% hydrochloric acid. The reaction was stopped by boiling. After adjusting the pH of the sugar solution in which the reaction was stopped to 6.0, 400 units of branching enzyme was added per solid content (g), and the reaction was carried out at 65 ° C. for 60 hours. The solution of this starch decomposition product was decolorized with activated carbon, ion-purified, and concentrated to a solid content concentration of 45% by mass. Further, the concentrated solution was pulverized with a spray dryer to obtain a starch decomposition product B.

[Starch decomposition product C]
A 30% by mass cornstarch slurry adjusted to pH 2.5 with 10% hydrochloric acid was decomposed to DE4 under a temperature condition of 140 ° C. After returning to normal pressure, the pH of the sugar solution whose reaction was stopped by neutralizing with slaked lime was adjusted to 5.8, and then α-amylase (Termamil 120L, manufactured by Novozymes) was added to the solid content (g). 0.02% by mass was added per unit, the reaction was carried out at 95 ° C., DE was measured over time, and when DE reached 8, the pH was adjusted to 4.0 with 10% hydrochloric acid, and the reaction was stopped by boiling. bottom. After adjusting the pH of the sugar solution in which the reaction was stopped to 6.0, 500 units of branching enzyme was added per solid content (g), and the reaction was carried out at 65 ° C. for 45 hours. Further, α-amylase (Termamil 120L, manufactured by Novozymes) was added in an amount of 0.02% by mass per solid content (g), the reaction was carried out at 80 ° C., and DE was measured over time. Then, the pH was adjusted to 4.0 with 10% hydrochloric acid, and the reaction was stopped by boiling. The solution of this starch decomposition product was decolorized with activated carbon, ion-purified, and concentrated to a solid content concentration of 50% by mass. Further, the concentrated solution was pulverized with a spray dryer to obtain a starch decomposition product C.

[Starch decomposition product D]
Α-Amylase (Termamil 120L, manufactured by Novozymes) was added to 30% by mass of tapioca starch slurry adjusted to pH 5.8 with 10% by mass of slaked lime, and 0.2% by mass per solid content (g) was added to a jet cooker (Jet Cooker). It is liquefied at a temperature of 110 ° C.), the liquefied liquid is kept warm at 95 ° C., DE is measured over time, and when DE10 is reached, the pH is adjusted to 4.0 with 10% hydrochloric acid, and the mixture is boiled. The reaction was stopped. The solution of this starch decomposition product was decolorized with activated carbon, ion-purified, and concentrated to a solid content concentration of 40% by mass. Further, the concentrated solution was pulverized with a spray dryer to obtain a starch decomposition product D.

[Starch decomposition product E]
Α-amylase (Crystase T10S, manufactured by Amano Enzyme Co., Ltd.) was added in an amount of 0.2% by mass per solid content (g) to 20% by mass of waxy cornstarch slurry adjusted to pH 5.8 with 10% by mass of slaked lime. It was liquefied with a jet cooker (temperature 110 ° C.), the liquefied liquid was kept warm at 95 ° C., DE was measured over time, and when it reached DE3, the pH was adjusted to 4.0 with 10% hydrochloric acid. , The reaction was stopped by boiling. After adjusting the pH of the sugar solution in which the reaction was stopped to 6.0, 100 units of branching enzyme was added per solid content (g), and the reaction was carried out at 65 ° C. for 5 hours. The solution of this starch decomposition product was decolorized with activated carbon, ion-purified, and concentrated to a solid content concentration of 30% by mass. Further, the concentrated solution was pulverized with a spray dryer to obtain a starch decomposition product E.

[Starch decomposition product F]
To 20% by mass of waxy cornstarch slurry adjusted to pH 5.8 with 10% by mass of slaked lime, α-amylase (Termamil 120L, manufactured by Novozymes) was added in an amount of 0.2% by mass per solid content (g), and a jet cooker (jet cooker) was added. It is liquefied at a temperature of 110 ° C.), the liquefied liquid is kept warm at 95 ° C., DE is measured over time, and when DE3 is reached, the pH is adjusted to 4.0 with 10% hydrochloric acid, and the mixture is boiled. The reaction was stopped. The solution of this starch decomposition product was decolorized with activated carbon, ion-purified, and concentrated to a solid content concentration of 30% by mass. Further, the concentrated solution was pulverized with a spray dryer to obtain a starch decomposition product F.

[Starch decomposition product G]
To 30% by mass of cornstarch slurry adjusted to pH 5.8 with 10% by mass of slaked lime, α-amylase (Spitzase HK, manufactured by Nagase ChemteX Corporation) was added in an amount of 0.2% by mass per solid content (g), and jetted. It was liquefied with a cooker (temperature 110 ° C.), the liquefied liquid was kept warm at 95 ° C., DE was measured over time, and when DE17 was reached, the pH was adjusted to 4.0 with 10% hydrochloric acid. The reaction was stopped by boiling. The solution of this starch decomposition product was decolorized with activated carbon, ion-purified, and concentrated to a solid content concentration of 50% by mass. Further, the concentrated solution was pulverized with a spray dryer to obtain a starch decomposition product G.

(3) Measurement For the starch decomposition products A to G obtained above, the contents of the branched chains having DE and DP8 to 9 in the starch decomposition products, the content of the fractions having a molecular weight of 14,000 to 80000, and DP3 to DP3, respectively. The content of the branched chain of 7 was measured by the method described above. The results are shown in Tables 3 and 5 below, together with the results of the experimental examples below.

<Experimental example 1>
In Experimental Example 1, how the specific sugar composition of the starch decomposition product affects the cooking of cooked rice was examined.

Specifically, after immersing 800 g of raw rice in 1160 g of water for 40 minutes, 1.5 parts by mass of starch decomposition products A to G are added to 100 parts by mass of raw rice, and the rice is cooked and steamed for 25 minutes. The cooked rice of Examples 1 to 3 and Comparative Examples 1 to 4 shown in Table 3 below was obtained. Reference Example 1 was obtained by immersing 800 g of raw rice in 1160 g of water for 40 minutes, cooking the rice, and steaming it for 25 minutes. After adjusting the temperature of each cooked rice to 25 ° C. with a vacuum cooler, the cooked rice was packed in a container with a lid and stored at 20 ° C. for 24 hours, and each cooked rice was subjected to a sensory evaluation of graininess by the method described above. The results are shown in Table 3.

As shown in Table 3, Examples 1 to 3 in which the content of the branched chain of DP8 to 9 is 7% by mass or more and the content of the fraction having a molecular weight of 14,000 to 80000 is in the range of 31 to 60% by mass are compared. Compared with Examples 1 to 4, the evaluation of the graininess of cooked rice was higher. That is, it was found that when the cooked rice improving agent according to the present invention is used, a higher cooked rice improving effect is exhibited when cooking cooked rice as compared with the case where a conventional starch decomposition product is used.

<Experimental example 2>
In Experimental Example 2, when cooking cooked rice, the effect of improving cooked rice due to the difference in the amount of the cooked rice improving agent added according to the present invention was examined.

Specifically, after immersing 800 g of raw rice in 1200 g of water for 40 minutes, rice was cooked by adding the amount of starch decomposition product C shown in Table 4 below to 100 parts by mass of raw rice, and steamed for 25 minutes. I got 4-5 rice. After adjusting the temperature of each cooked rice to 25 ° C. with a vacuum cooler, the cooked rice was packed in a container with a lid and stored at 20 ° C. for 24 hours, and each cooked rice was subjected to a sensory evaluation of graininess by the method described above. The results are shown in Table 4.

As shown in Table 4, in all of Examples 4 to 7, the evaluation of the graininess of cooked rice was good, and it was confirmed that the effect of the cooked rice improving agent tended to increase in a dose-dependent manner of the starch decomposition product C.

<Experimental example 3>
In Experimental Example 3, how the specific sugar composition of the starch decomposition product affects the production of cooked rice processed food was examined.

Specifically, after immersing 800 g of raw rice in 1240 g of water for 40 minutes, 0.6 parts by mass of edible oil and fat (high oleic sunflower oil (manufactured by Showa Sangyo Co., Ltd., the same applies hereinafter)) with respect to 100 parts by mass of raw rice. (Coloring was performed by adding 0.2% by mass of β-carotene only when evaluating the dispersibility of fats and oils and the workability during rice ball molding. The same applies hereinafter.)) And 5.0 parts by mass of starch decomposition products A to G. The rice was added, stirred lightly, and then cooked, and steamed for 25 minutes after cooking to obtain rice balls of Examples 8 to 10 and Comparative Examples 5 to 8. After immersing 800 g of raw rice in 1240 g of water for 40 minutes, add 0.6 parts by mass of edible oil (sunflower oil with high oleic acid) to 100 parts by mass of raw rice, stir lightly, and cook the rice for 25 minutes. The steamed product was used as Reference Example 2. The dispersibility of fats and oils in water was evaluated before cooking rice, and the dispersibility of fats and oils in cooked rice was evaluated after cooking rice. The temperature of each cooked rice obtained was adjusted to 25 ° C, and 3 kg of each cooked rice was put into a rice ball molding machine (small molding machine GKT3000, Fuji Seiki Co., Ltd.) and adjusted to 95 g per piece. Rice balls were manufactured and workability was evaluated. Each of the produced rice balls was packed in a container with a lid and stored at 20 ° C. for 24 hours, and then the graininess, looseness, and luster of the rice balls were sensory-evaluated by the method described above. The results are shown in Table 5 below.

As shown in Table 5, Examples 8 to 10 in which the content of the branched chains of DP8 to 9 is 7% by mass or more and the content of the fraction having a molecular weight of 14,000 to 80000 is in the range of 31 to 60% by mass are compared. Compared to Examples 5 to 8, the dispersibility of fats and oils in water, the dispersibility of fats and oils after cooking rice, the workability during rice ball molding, and the sensory evaluation of the graininess, looseness, and luster of rice balls are all evaluated. Was expensive. That is, it was found that when the cooked rice improving agent according to the present invention is used, a higher cooked rice improving effect is exhibited at the time of producing the processed cooked rice food as compared with the case where the conventional starch decomposition product is used.

For reference, with reference to Reference Example 2 and Example 10, the state of the kettle before cooking rice and the state of the cooked rice after cooking as viewed from the bottom are shown in FIGS. 1 and 2, respectively. As shown in FIGS. 1 and 2, by using the cooked rice improving agent according to the present invention, the dispersibility of fats and oils in water during cooking is improved, and the dispersibility of fats and oils in cooked rice after cooking is also improved. It turned out.

<Experimental example 4>
In Experimental Example 4, the effect of improving cooked rice due to the difference in the amount of the cooked rice improving agent added according to the present invention was examined during the production of processed cooked rice.

Specifically, after immersing 800 g of raw rice in 1240 g of water for 40 minutes, 0.6 parts by mass of high oleic sunflower oil with respect to 100 parts by mass of raw rice and the amount of starch decomposition product C shown in Table 6 below. Was added, and the rice was cooked after being lightly stirred, and steamed for 25 minutes after cooking to obtain cooked rice of Examples 11-14. The dispersibility of fats and oils in water was evaluated before cooking rice, and the dispersibility of fats and oils in cooked rice was evaluated after cooking rice. The temperature of each cooked rice obtained was adjusted to 25 ° C, and 3 kg of each cooked rice was put into a rice ball molding machine (small molding machine GKT3000, Fuji Seiki Co., Ltd.) and adjusted to 95 g per piece. Rice balls were manufactured and workability was evaluated. Each of the produced rice balls was packed in a container with a lid and stored at 20 ° C. for 24 hours, and then the graininess, looseness, and luster of the rice balls were sensory-evaluated by the method described above. The results are shown in Table 6 below.

As shown in Table 6, as the amount of starch decomposition products added increases, the dispersibility of fats and oils in water, the dispersibility of fats and oils in cooked rice after cooking, the workability during rice ball molding, and the graininess and loosening of rice balls. It was found that the evaluation was improved in all the sensory evaluations of sex and luster. That is, it was confirmed that the effect of the cooked rice improver of the present invention during the production of processed cooked rice tended to increase in a dose-dependent manner.

<Experimental Example 5>
In Experimental Example 5, when cooking cooked rice, the effect of improving cooked rice when it was added in the form of a mix containing a starch decomposition product and edible oils and fats in advance as a cooked rice improving agent was examined.

Specifically, first, the starch decomposition products and the edible fats and oils are mixed in the blending amounts shown in Table 7 below so as to be uniform, and mixed (rice improver) (dispersity of fats and oils, workability (separation from the kettle)). 0.2% by mass of β-carotene was added to edible fats and oils and colored.) After immersing 800 g of raw rice in 1240 g of water for 40 minutes, a pre-produced mix (rice improver) is added in the amounts shown in Table 7 below, and the rice is cooked after being lightly stirred, and steamed for 25 minutes after cooking. I got 22 cooked rice. The dispersibility of fats and oils in water was evaluated before cooking rice, and the dispersibility of fats and oils in cooked rice after cooking rice and the workability such as leaving the kettle were evaluated. For each cooked rice, after adjusting the temperature to 25 ° C with a vacuum cooler, the cooked rice was packed in a container with a lid and stored at 20 ° C for 24 hours. went. The results are shown in Table 7.

As shown in Table 7, even when the cooked rice improving agent of the present invention is added in the form of a mix containing a starch decomposition product and an edible oil / fat in advance, the cooked rice improving effect is exhibited as in each of the above-mentioned experimental examples. It was proved. Further, as in Experimental Examples 2 and 4, as the amount of the decomposition product added increases, the dispersibility of the fat and oil in water, the dispersibility of the fat and oil after cooking, the workability such as leaving the kettle, and the grains of cooked rice It was found that the evaluation was improved in all of the sensory evaluations of feeling, looseness, and luster. That is, it was confirmed that the effect of the cooked rice improver of the present invention during the production of processed cooked rice tended to increase in a dose-dependent manner. Further, from the results of Examples 21 and 22, it was found that the effect of improving rice rice was improved by adding rice flour to the cooked rice improving agent according to the present invention.

For reference, FIGS. 3 and 4 show the state of the pot before cooking, the state of the pot after cooking as viewed from the top, and the state of the cooked rice as viewed from the bottom of Examples 16 and 21, respectively. .. As shown in FIGS. 3 and 4, it was found that by using the cooked rice improving agent according to the present invention, the dispersibility of fats and oils in water during rice cooking is improved, and the dispersibility of fats and oils after cooking rice is also improved. rice field.

Further, when Examples 9 and 10 in Experimental Example 3 and Examples 15 and 16 are compared, all the results are better in Examples 15 and 16 even though the amount of edible oil and fat added is smaller. It was a result. Further, comparing Example 12 and Example 18 in Experimental Example 4, although the amount of edible oil and fat added to Example 18 is smaller, the dispersibility of the oil and fat in water, the separation of the oil and fat from the kettle, etc. Good results were obtained in the workability and the sensory evaluation of the graininess, looseness, and luster of cooked rice. In particular, the looseness was greatly improved in Examples 15, 16 and 18. From this result, it is better to mix the starch decomposition product and the edible oil and fat before adding it than to add the starch decomposition product and the edible oil and fat separately, because the dispersibility of the oil and fat in water is improved. It was found that the amount of edible oil and fat added for improvement can be reduced, and that when the same amount of edible oil and fat is added, the looseness can be greatly improved.

Claims (7)

The active ingredient is a starch decomposition product containing a branched sugar consisting of a main chain and a branched chain that satisfy the following (1) and (2) .
A cooked rice improving agent containing 0.5 parts by mass or more of the starch decomposition product with respect to 100 parts by mass of raw rice used for the cooked rice to be improved.
(1) 7 ≦ x; However, x is the content (mass%) of the branched chain having a glucose polymerization degree (DP) of 8 to 9 in the starch decomposition product.
(2) 31 ≦ y ≦ 60; However, y is the content (mass%) in the starch decomposition product of the fraction having a molecular weight of 14,000 to 80,000. The cooked rice improving agent according to claim 1, wherein x satisfies the following (1').
(1') 8 ≤ x The cooked rice improving agent according to claim 1 or 2, wherein y satisfies the following (2').
(2') 35 ≤ y ≤ 60 Any of claims 1 to 3, wherein the fraction having a molecular weight of 14,000 to 80000 of the starch decomposition product contains at least a part of the branched sugar having a branched chain having a glucose polymerization degree (DP) of 8 to 9. The cooked rice improver described in item 1. The cooked rice improving agent according to any one of claims 1 to 4, which comprises edible oil and fat. The cooked rice improving agent according to claim 5, wherein the mass ratio of the starch decomposition product to the edible oil / fat is 2: 1 to 15: 1. Cooked rice or cooked rice, which comprises a step of adding 0.5 parts by mass or more of a starch decomposition product containing a branched sugar composed of a main chain and a branched chain satisfying the following (1) and (2) to 100 parts by mass of raw rice. Manufacturing method of cooked rice processed food.
(1) 7 ≦ x; However, x is the content (mass%) of the branched chain having a glucose polymerization degree (DP) of 8 to 9 in the starch decomposition product.
(2) 31 ≦ y ≦ 60; However, y is the content (mass%) in the starch decomposition product of the fraction having a molecular weight of 14,000 to 80,000.

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