JP2001258487A - Method for producing excellent quality cooked rice - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing an excellent quality cooked rice, excellent in antiseptic capability (preserving property) and capable of suppressing the generation of an irritating smell such as an acetic acid smell after the cooking which is a matter of course, and on re-heating the cooked rice, and to obtain an improving agent for cooking rice, capable of producing such cooked rice simply. SOLUTION: (1) This method for producing excellent quality cooked rice is characterized by adding 0.0005-0.05 wt.% glycine per raw rice on cooking the rice added with an acetic acidcontaining improving agent for cooking rice before cooking the rice, and cooking the rice so that the pH of the cooked rice becomes 5.0-6.2. (2) The acetic acid and glycine-containing improving agent for cooking rice contains 0.3-500 pts.wt. glycine per 100 pts.wt. acetic acid and exhibits pH at 1.6-5.0. (3) The method for producing excellent quality rice is characterized by adding the acetic acid and glycine-containing improving agent (2) for cooking rice before cooking the rice and cooking so that the pH of the cooked rice becomes 5.0-6.2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a method for producing cooked rice of excellent quality and a rice cooking improver.
It has excellent antiseptic power (preservability) and after cooking rice,
A method for producing high quality cooked rice that can suppress the generation of pungent odors such as acetic acid odor even when reheating cooked rice, and rice cooker that can easily produce such cooked rice And improving agents.

[0002]

2. Description of the Related Art Cooked rice is produced by adding water to raw rice, heating the cooked rice, and cooking the cooked rice. In recent years, along with the spread of eating habits called so-called "meal meals", purchasing lunches and prepared dishes sold at supermarkets and convenience stores, etc. The production of white rice itself and cooked rice, which is processed into bento and rice balls, has been increasing.

As described above, cooked rice that is used after being processed into a lunch box, rice ball, or the like, is provided to a dining table after a relatively long time has passed since it was produced. For this reason, it is necessary to impart storability such as prevention of putrefaction due to the growth of microorganisms and prevention of starch aging of cooked rice, and various processing methods and rice cooking improvers have been developed.

Japanese Unexamined Patent Publication (Kokai) No. 5-176694 discloses that glucono-delta-lactone, an organic acid or salts thereof are added before steaming with a steamer, which is not cooked rice but imparts antiseptic properties to steamed cooked rice. PH of cooked rice after steaming
Is set to 4.0 to 4.8. In general, cooked rice for ready-to-eat meals is often eaten without any seasoning, and is often eaten after being reheated in a microwave oven or the like. Therefore, as organic acids and salts thereof mainly used in the rice cooker, so-called non-volatile acids such as gluconic acid and citric acid and salts thereof, which hardly generate an acid odor even when reheated in a microwave oven or the like, are used. Sometimes used. However, such non-volatile acids are not always sufficient in terms of preservative power.

[0005] In terms of preservative power, acetic acid and its salts are the best among organic acids and salts thereof. Therefore, a rice cooker using acetic acid or its salts as a main component has also been developed. ing. However, acetic acid is one of the so-called volatile acids, and tends to impart a unique pungent odor to cooked rice. In particular, when cooked rice to which this kind of rice cooker is added is reheated in a microwave oven or the like, there is a disadvantage that acetic acid odor is generated more strongly and the flavor is remarkably reduced.

Particularly, the acetic acid-containing rice cooker is used so that the acetic acid concentration per raw rice is about 0.01 to 0.16% by weight, and the pH of cooked rice is 5.0 to 6.2.
However, rice cooked in such a state has a drawback that the odor of acetic acid is felt even before reheating, and acetic acid is more likely to evaporate when reheated by a microwave oven or the like, so that the odor of acetic acid is further increased. there were.

[0007] Therefore, there is a strong demand for the development of a method that is excellent in preservative power (preservability) and that can suppress generation of irritating odor such as acetic acid odor as much as possible after re-heating of cooked rice as well as after cooking. Was.

[0008]

DISCLOSURE OF THE INVENTION The present invention solves the above-mentioned conventional problems, is excellent in antiseptic power (preservability), and has an odor of acetic acid not only after cooking rice but also when reheating cooked rice. It is an object of the present invention to provide a method for producing cooked rice of excellent quality, which can suppress the generation of an unpleasant irritating odor, and a rice cooker which can easily produce such cooked rice. is there.

[0009]

Means for Solving the Problems In view of the above problems, the present inventors have made intensive studies and found that the preservative power (preservability) was first obtained.
Acetic acid-containing rice cooker which is superior to acetic acid, and particularly when acetic acid-containing rice cooker is added at pH 5.0 to 6.2 to produce cooked rice, the acetic acid-containing rice cooker is improved. By adding a very small amount of glycine, one of the amino acids, when adding and using the pre-cooking agent, the odor of acetic acid in cooked rice can be suppressed. It has been found that the generation of irritating odor can be significantly suppressed, and based on this finding, the present invention has been completed.

That is, according to the first aspect of the present invention, the pH of cooked rice is adjusted by adding an acetic acid-containing rice cooker before cooking.
A method for producing cooked rice of excellent quality, characterized in that 0.0005 to 0.05% by weight of glycine is added per raw rice when rice is cooked so as to be 0 to 6.2. is there.

The present invention according to claim 2 provides an acetic acid- and glycine-containing rice cooker containing 0.3 to 500 parts by weight of glycine per 100 parts by weight of acetic acid and having a pH of 1.6 to 5.0. It is.

[0012] According to a third aspect of the present invention, the rice cooker containing acetic acid and glycine according to the second aspect is added before cooking rice so that the cooked rice has a pH of 5.0 to 6.2. It is intended to provide a method for producing cooked rice of excellent quality, characterized by the following.

Glycine is known to have an antiseptic function, and there are already examples of food preservatives using glycine in combination with organic acids and their salts and acetates. For example,
Japanese Patent Application Laid-Open No. 8-196252 discloses a food shelf-life improving agent and a preservative food characterized by containing lysozyme, an amino acid or a salt thereof, an organic acid or a salt thereof and an acetate.

However, in the present invention, lysozyme, which is an antibacterial substance, is essential. In addition, the concentration of glycine added to food in the examples is a relatively high concentration of 0.05% by weight or more. The effect of suppressing acetic acid odor by adding glycine as in the invention has not yet been disclosed.

In Japanese Patent Application Laid-Open No. 9-23860, food preservation is carried out by mixing vinegar or acetic acid with one or more organic acids and / or organic acid salts selected from a specific group. It is disclosed that the acidity of acetic acid can be reduced by adding an amino acid such as glycine to the acetic acid. However, in this case, the addition of food preservatives to
It is carried out at 5.0 or less, preferably at pH 3.0 to 4.8, and the final concentration of amino acid such as glycine added to food is preferably 0.1 to 5% by weight. The concentration is relatively high, almost as in the case of the enhancer.

Furthermore, Japanese Patent Application Laid-Open No. 7-203942 discloses an invention relating to processed vinegar for food, but discloses the presence of glycine as one of the vinegar having an effect of reducing the acidity of vinegar. However, in this case, the concentration of glycine added to the food is 0.1 to 0.1.
It was calculated to be 3% by weight and was a relatively high concentration.

[0017] In contrast to these conventional reports, in the present invention, the acetic acid-containing rice-improving agent is used to improve the pH of cooked rice before cooking.
Is added so as to be 5.0 to 6.2, and the amount of glycine is 0.0005 to 0.05% by weight per raw rice, more preferably 0.001 to 0.015%. Glycine differs from these inventions in that glycine is not expected to have a preservative effect, and is not an acetic acid taste but an acetic acid odor (improvement of aroma).

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. The present invention according to claim 1 relates to a method for producing cooked rice with excellent quality, and adds an acetic acid-containing rice cooker before cooking to cook rice so that the pH of cooked rice becomes 5.0 to 6.2. At this time, glycine is added in an amount of 0.0005 to 0.05% by weight per raw rice.

In the present invention according to claim 1, the pH of cooked rice is adjusted to 5.0 by adding an acetic acid-containing rice cooker before cooking.
Cook rice to ~ 6.2. The acetic acid-containing rice cooker used in the present invention according to claim 1 contains acetic acid. The acetic acid referred to here includes acetate in addition to acetic acid itself. In the present invention according to claim 1, acetic acid itself or one or more acetates may be used, or Acetic acid may be used in combination with one or more acetate salts. The pH of the acetic acid-containing rice cooker is adjusted to 1.6 to 5.0.

The acetic acid used may be chemically synthesized, but it is desirable to use so-called vinegar produced by fermentation as a source of acetic acid. Examples of the acetate include addition salts of acetic acid with an alkali metal such as sodium acetate and potassium acetate, and addition salts of acetic acid with an alkaline earth metal such as calcium acetate and magnesium acetate.

Such an acetic acid-containing rice cooker contains, if necessary, organic acids other than acetic acid (such as gluconic acid and citric acid) and salts thereof, as long as the object of the present invention is not impaired. And, if necessary, may contain a predetermined amount of various salts, sugars, sugar alcohols and the like in order to add a starch aging preventing effect.

Such an acetic acid-containing cooked rice improving agent is added before cooking rice, that is, before heating during cooking. The amount of the acetic acid-containing cooked rice improver is 0.0
About 1 to 0.16% by weight, preferably 0.03 to 0.0
It is about 8% by weight.

As a method of cooking rice, the pH of cooked rice is adjusted to 5.0 to 5.0 by adding the acetic acid-containing rice cooker before cooking.
Except for cooking rice to 6.2, preferably 5.20 to 5.80, a commonly practiced method may be used, and there is no limitation. Here, if the pH of the cooked rice is less than 5.0, the sourness due to the organic acid becomes strong, while if the pH of the cooked rice exceeds 6.2, acetic acid and / or
Alternatively, there is no point in adding a salt thereof, and neither is preferred.

Usually, the cooked rice has a pH of 5.0 to 6.2.
When the acetic acid-containing rice cooker is added so that acetic acid smell is generated after cooking, and further reheating, the acetic acid smell becomes stronger, but surprisingly, glycine is contained in a specific ratio as described below. Thus, an excellent effect of preventing the odor of acetic acid after cooking and suppressing the odor of acetic acid after reheating can be obtained.

The present invention according to claim 1 is characterized in that glycine is allowed to coexist when rice is cooked using the acetic acid-containing rice cooker as described above. The addition amount of glycine is 0.0005 to 0.5 as an addition concentration to raw rice.
05% by weight, preferably 0.001 to 0.015% by weight
And If the amount of glycine is less than 0.0005% by weight, the effect of glycine on controlling the acetic acid odor is hardly exhibited, while if it exceeds 0.05% by weight, an off-flavor such as burnt odor becomes strong. However, the quality of cooked rice is deteriorated, and neither is preferred. In particular, it is more preferable that the amount of glycine added is 0.001 to 0.015% by weight, since the acetic acid odor-suppressing effect of glycine is more strongly exerted and no adverse effect of glycine is observed.

In the present invention according to the first aspect, since it is necessary to coexist with the acetic acid-containing rice cooking improver as described above, it is necessary to add glycine before cooking, that is, before heating during cooking. is there. Even if it is added after cooking rice, the desired effect of suppressing acetic acid odor by adding glycine cannot be obtained.

Glycine is used as a food additive, but other food materials containing a high concentration of glycine may be used.

As described above, it is possible to produce cooked rice of excellent quality as described in the first aspect of the present invention. The cooked rice cooked in this manner is appropriately packed, if necessary, in a container, used through low-temperature distribution, etc., and eaten by performing reheating or the like in a microwave oven or the like as necessary. Will be.

The effect of adding glycine and the acetic acid-containing rice-cooking improver can be obtained even if they are separately prepared and added. It is more preferable to make acetic acid and glycine-containing rice-cooking improver that is formulated by incorporating glycine into a single product.

The present invention according to claim 2 provides an acetic acid- and glycine-containing rice-cooking improver which is formulated as an integrated product. As described above, the addition amount of the acetic acid-containing rice cooker at the time of cooking rice is 0.01% as acetic acid amount per raw rice.
The glycine concentration range of about 0.16% by weight and the acetic acid odor-suppressing effect is in the range of 0.1% per raw rice.
0005-0.05% by weight. Based on this point, the blending ratio of acetic acid and glycine in the case of acetic acid and glycine-containing rice cooker is, as described in claim 2, 0.3 to 500 glycine per 100 parts by weight of acetic acid.
Parts by weight, preferably 0.6 to 150 parts by weight, more preferably 1.2 to 50 parts by weight. This acetic acid and glycine-containing rice cooker has a pH of 1.6 to 5.0,
Preferably 2.0-4.6, more preferably 2.2-
Adjusted to 3.5. Here, the pH of the improver is 1.
If it is less than 6, the pH of the cooked rice will be less than 5.0, while if the pH of the improver exceeds 5.0, the amount of organic acid salt contained in the cooked rice will increase, and the taste will be unpleasant. Both are not preferred.

Further, the above-mentioned rice cooker containing acetic acid and glycine is added before cooking rice so that the pH of cooked rice becomes 5.0.
It is characterized by cooking rice so that it becomes ~ 6.2.
This is the third aspect of the present invention. The present invention according to claim 3 is carried out in the same manner as in the present invention according to claim 1, except that the acetic acid and glycine-containing rice cooker described in claim 2 is used.

In this way, it is excellent in preservative power (preservability) and can suppress generation of irritating odor such as acetic acid odor not only after cooking rice but also when re-heating cooked rice.
Rice cooked rice of excellent quality can be obtained, and a rice cooker which can easily produce such cooked rice can be obtained.
The cooked rice cooked in this manner is, as described above, appropriately packed in a container as needed, and is used through low-temperature distribution and the like, and further subjected to reheating in a microwave oven or the like as necessary. I will go and eat.

The following tests (Test Examples 1 and 2) were carried out to confirm the preservative properties of rice cooked and the effect of suppressing acetic acid odor when glycine was added when using an acetic acid-containing rice cooker. Was.

Test Example 1 As acetic acid-containing rice cookers, those having the compositions shown in Tables 1 to 3 were prepared (acetic acid-containing rice cookers A to C).

[0035]

[Table 1] Table 1 (acetic acid-containing rice cooker A)

[0036]

Table 2 Table 2 (acetic acid-containing rice cooker B)

[0037]

[Table 3] Table 3 (Rice cooker containing acetic acid C)

When rice is cooked using the acetic acid-containing rice-improving agents A, B and C described above, the concentration of the glycine is varied in various amounts while glycine is added in an amount of 0.0001% by weight to 0.1% by weight. The acetic acid odor suppressing effect was compared with each other in a stepwise manner within the range. 4th result
It is shown in the table. The preservative power was evaluated by measuring the viable cell count of cooked rice after culturing at 30 ° C. for 48 hours by the following method. The results are described below.

In Table 4, the pH of the cooked rice cooked with acetic acid-containing rice cooker alone or with the addition of acetic acid-containing cooker and glycine was adjusted to about 2.5 with distilled water.
It is the result of diluting it twice, homogenizing with a homogenizer, and measuring pH.

The number of viable bacteria was 1 g of cooked rice after cooking.
It was inoculated with 10 ¹ B. subtilis per the results of measuring the number of viable bacteria per rice 1g after 48 hours incubation at 30 ° C. with subsequent incubator. The viable cell count was measured using a nutrient medium according to a conventional method.

The sensory evaluation (acetic acid odor and off-flavor) is the result of evaluating the fragrance immediately after reheating the cooked rice after cooking at 20 ° C. for 5 hours and reheating in a microwave oven.

The evaluation of the acetic acid odor is as follows. X: Strong odor of acetic acid. Δ: odor of acetic acid is slightly felt. ：: Almost no odor of acetic acid is felt. A: No acetic acid smell was felt.

The evaluation of the off-flavor is as follows. ×: Strong odor. ：: Almost no off-flavor is felt. A: No off-flavor is felt.

[0044]

Table 4 (Effect of glycine addition)

[Footnotes to Table 4] *: The amount of acetic acid added includes sodium acetate.

From the results in Table 4, the following is clear. First, in Test Example 1, the acetic acid-containing rice cooker was added such that the acetic acid concentration per raw rice was about 0.01 to 0.156% by weight. In this range, 0.0005% by weight of glycine was added. % -0.1% by weight, the cooked rice obtained can cope with the occurrence of acetic acid odor even when reheated in a microwave oven.

However, when glycine was coexisted at a concentration higher than 0.05% by weight, an unpleasant smell such as a burnt smell increased with an increase in the concentration of glycine, and the quality of cooked rice deteriorated. On the other hand, when glycine was allowed to coexist at 0.0001% by weight or when glycine was not added, the acetic acid odor remained, and the quality of cooked rice was low. From the above results, the glycine addition concentration range was 0.0005 to 0.0
It was confirmed that the content was 5% by weight, preferably 0.001 to 0.015% by weight.

The microbial test results of cooked rice after storage at 30 ° C. for 48 hours show that 100,000 cells / rice in all the test plots.
It showed that there was no problem when it was less than g, and it was found that all had sufficient antiseptic power (preservability).

Test Example 2 (Example in which glycine was added after cooking rice; comparative test example) In Test Example 1, glycine was added simultaneously with the acetic acid-containing cooked rice improver before heating the rice, but in Test Example 2, glycine was added. A test was performed in which the contained rice-improving agent was added separately from glycine before heating the rice, and the rice was cooked. After the rice was cooked, glycine was added at the same concentration as in Test Example 1. As a result, the acetic acid odor suppressing effect was very weak as compared with Test Example 1. Therefore,
It has been found that it is essential to add glycine together with the acetic acid-containing rice cooker before heating during cooking.

From the above results, when rice was cooked using the acetic acid-containing rice-improving agent so that the pH of the cooked rice became 5.0 to 5.8, glycine was added in an amount of 0.0005 to 0.0 before heating the rice.
5% by weight, preferably 0.001 to 0.015% by weight
It has been found that by containing the acetic acid, it is possible to remarkably suppress the acetic acid odor when the cooked rice is reheated.

[0051]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to the following Examples.

Example 1 (Production of rice cook improver D containing glycine and acetic acid) A rice cook improver containing glycine and acetic acid as shown in Table 5 below was prepared.

[0053]

Table 5 (Composition of rice cooking improver D containing glycine and acetic acid)

Example 2 (Production of Rice Cooked Rice Using Glycine and Acetic Acid-Containing Rice Cooker D) Rice cooked rice was produced using the above glycine and acetic acid-containing rice cooker D. That is, raw rice (Koshihikari)
6.5 kg of rice was washed and immersed in water for about 2 hours. Then
After draining, put it into a 5-cooker gas cooker, and water 8k
After adding g, 65 mL of rice cooking improver D containing glycine and acetic acid was added, and the mixture was stirred and heated by a conventional method to cook rice. Thereafter, the heating was stopped and the rice was cooked through a steaming process for 30 minutes. The cooked rice thus prepared was cooled, and then filled into a 200 g pack container to prepare white rice. This white rice could be eaten deliciously with almost no smell of acetic acid, even after being reheated in a microwave oven after being stored at 20 ° C. for 24 hours.

[0055]

According to the first aspect of the present invention, it has excellent antiseptic power (preservability) and an irritating odor such as acetic acid odor not only after cooking rice but also during reheating after a while after production. Can be suppressed. Further, according to the present invention according to claim 2, since an acetic acid- and glycine-containing acetic acid-containing rice-cooking improver is provided, such cooked rice can be provided for simple production. Furthermore, according to the third aspect of the present invention, a method for producing cooked rice using the acetic acid-containing and glycine-containing acetic acid-containing rice-cooking improver is provided. Of course, generation of a pungent odor such as acetic acid odor can be suppressed even when reheating is performed after a lapse of some time after the production. Therefore, the present invention can be effectively used for the production of cooked rice which is processed into bento, onigiri, prepared foods and the like, including the production of white rice itself sold in supermarkets and convenience stores, etc. Above is useful.

Claims (3)

[Claims] 1. When cooking rice so as to have a pH of 5.0 to 6.2 by adding an acetic acid-containing rice cooker before cooking, glycine is added in an amount of 0.0005 to 0.05 per raw rice. A method for producing cooked rice of excellent quality, characterized by adding by weight. 2. Glycine 0.3 parts per 100 parts by weight of acetic acid.
An acetic acid- and glycine-containing rice cooker containing up to 500 parts by weight and having a pH of 1.6 to 5.0. 3. The rice cooked rice-improving agent containing acetic acid and glycine according to claim 2 is added before cooking to make the cooked rice pH 5.0 to 5.0.
A method for producing cooked rice of excellent quality, characterized in that rice is cooked so as to be 6.2.