JP6261417B2 - Processed cooked rice and method for producing the same - Google Patents

Description

  The present invention relates to processed cooked rice and a method for producing the same. More specifically, the present invention relates to processed cooked rice with improved texture and taste and a method for producing the same.

  In recent years, demand for processed cooked rice that can be provided immediately has increased due to the externalization of food and changes in family composition. In addition, demand for processed cooked rice is increasing as an emergency food and a preserved food.

  As processed rice, frozen rice, retort rice, chilled rice, and dried rice are known. Furthermore, as dried rice, alpha rice, expanded dried rice, vacuum freeze dried rice, and the like are known.

  Here, pregelatinized rice is obtained by pregelatinizing starch by hydrothermal treatment such as cooking rice or steaming and then drying. In addition, expanded dry rice is obtained by gelatinizing starch and then drying it at a high temperature to expand the structure. Furthermore, the vacuum freeze-dried rice is a product obtained by gelatinizing starch and then freeze-drying it.

  In order to eat dried cooked rice, it is common to add water to cook and restore, or add hot water to restore. However, since dried rice once dried pre-gelatinized rice, there was a problem that the restoration was not sufficient or the texture and taste were poor even after restoration.

  Therefore, several methods have been disclosed for improving the recoverability. For example, alpha rice using low amylose rice having an amylose content of 15% by weight or less is disclosed as dry rice (see Patent Document 1). Moreover, in the alpha rice production process, a method of adding trehalose during rice cooking is disclosed (see Patent Document 2).

JP 2004-65077 A JP 7-31389 A

  Although the dry rice described in the above publication has improved texture and taste, it is still difficult to say that it is satisfactory. For example, in the case of pregelatinized rice using low amylose rice, there is a problem that the low amylose rice itself is sticky and the rice is not easily loosened when dried. In addition, alpha rice using trehalose at the time of cooking rice has a problem that the production cost increases because trehalose is expensive.

  The present invention has been made in view of the above problems. That is, an object of the present invention is to provide cooked cooked rice with improved texture and taste and reduced manufacturing costs.

  The present inventors diligently studied the texture and dryness of dried rice. And as a result of examining rice cooking conditions, after cooking rice with alkaline water, processed rice using cooked rice neutralized with acidic aqueous solution has improved resilience, texture and taste compared to conventional processed rice As a result, the present invention has been completed.

  Here, “neutralization” in the present invention means to return the alkalinity closer to acidity. Therefore, it is not necessary that the pH is strictly 7.0, and it is sufficient that the pH is around 7.0.

  In order to solve the above problems, the present invention provides processed cooked rice using cooked rice that has been cooked with an alkaline aqueous solution and then neutralized with an acidic aqueous solution.

  Here, “processed cooked rice” as used in the present invention means frozen cooked rice, retort cooked rice, chilled cooked rice, and dried cooked rice. The “cooked rice” is not limited to ordinary white rice, and includes brown rice, red rice, rice cake, miscellaneous cooking, cooked cooked rice with kaya and seasonings.

  According to such a configuration, by cooking with an alkaline aqueous solution, gelatinization of rice can be promoted, and the texture and taste can be improved. On the other hand, if the alkalinity is strong, the cooked rice has a yellow color, and there is a problem such as leftover in the cooked rice. However, by neutralizing after cooking, cooked rice with improved color tone, texture and taste can be obtained. Moreover, by using this cooked rice, even in processed rice, color tone, restorability, taste and texture can be improved.

  In the above-described configuration, the processed cooked rice is preferably pregelatinized rice, expanded dried rice, or freeze-dried rice.

  According to such a configuration, long-term storage is possible, and even when restored, the texture and taste superior to conventional processed cooked rice can be enjoyed.

  In order to solve the above-mentioned problems, the present invention provides a method for producing processed cooked rice, in which an immersion step of immersing in an alkaline aqueous solution, a rice cooking step of cooking together with the alkaline aqueous solution, and neutralizing with an acidic aqueous solution after the rice cooking Provided is a method for producing processed cooked rice comprising a summing step and a processing step of processing the neutralized cooked rice.

  According to such a configuration, gelatinization of rice can be promoted, and color tone, restorability, texture and taste can be improved. Moreover, by neutralizing after cooking rice, it is possible to suppress the gummy due to alkali.

  In the above-described configuration, the neutralization step is preferably performed by adding an acidic aqueous solution to the cooked rice.

  According to this composition, it can neutralize, giving water to cooked rice further. In addition, processed cooked rice using cooked rice with improved color tone, texture and taste can be produced.

  According to the present invention, cooked rice with accelerated gelatinization can be created rather than rice cooked with water. And by using this cooked rice, it is possible to create a processed cooked rice that has good restoration properties and excellent texture and taste.

  Hereinafter, preferred embodiments for carrying out the present invention will be described. In addition, embodiment described below shows an example of typical embodiment of this invention, and, thereby, this invention is not interpreted narrowly.

(Raw material rice)
The raw material rice used in the present invention is not particularly limited, such as japonica, indica, long grain, and short grain rice, and various kinds of rice can be used. Furthermore, old rice can also be used effectively.

(Alkaline aqueous solution)
Examples of the alkaline aqueous solution used in the present invention include those obtained by dissolving electrolyzed water or an alkaline substance in water. Examples of the alkaline substance include potassium carbonate, sodium carbonate, sodium hydrogen carbonate, trisodium phosphate and the like. Of these, there is no particular limitation as long as it does not affect the smell or taste.

  Here, the pH of the alkaline aqueous solution may be a pH that can bring the pH of the cooked rice before neutralization into a desired range in consideration of the pH buffering action of the raw rice. The desired pH of the cooked rice before neutralization is preferably 7.3 to 9.5, and more preferably 8.0 to 9.3.

(Acidic aqueous solution)
Examples of the acidic aqueous solution used in the present invention include aqueous solutions of lactic acid, acetic acid, citric acid, carboxylic acid, ascorbic acid and the like. Of these, there is no particular limitation as long as it does not affect the smell or taste.

  Here, pH of acidic aqueous solution should just be pH which can make pH of rice cooking rice after neutralization into a desired range after considering the pH buffer action of rice cooking rice. The desired pH of the cooked rice after neutralization is preferably pH 6.8 to 7.5, and more preferably pH 7.0 to 7.3. If the pH is less than 6.8, the sourness becomes tight even after the processed cooked rice. On the other hand, if the pH is greater than 7.5, scum remains.

  Next, the rice cooking process will be described.

  First, the rice washing process will be described. In the rice washing process, the raw rice after milling is washed. At this time, the rice washing method is not particularly limited, and a known technique can be used. An alkaline aqueous solution may be used from the rice washing step.

  Next, the immersion process will be described. In the dipping process, the washed rice is dipped in water or an alkaline aqueous solution to absorb water. The soaking time depends on the time, temperature, and the type and state of the rice, but it is preferably soaked for 30 minutes or more if it is white rice. By immersing the raw rice after washing in water or an alkaline aqueous solution, the rice absorbs water, and cooked rice with good texture and taste can be obtained. In the present invention, it is preferable to immerse in an alkaline aqueous solution.

  When the raw rice after washing is immersed in an alkaline aqueous solution, an alkaline aqueous solution prepared in advance may be used, or an alkaline substance may be added after the raw rice after washing is immersed in water. When the alkaline substance is added later, it is preferable to stir so as not to cause density unevenness.

  Further, the timing of immersing the raw rice in the alkaline aqueous solution is not particularly limited as long as it is before cooking rice, but it is preferable to immerse the raw rice in the alkaline aqueous solution after the rice washing. Thereby, the water absorption of raw material rice can be raised. In addition, after immersing raw rice in water, an alkaline substance may be added to prepare an alkaline aqueous solution.

  In the present invention, enzymes such as oil, emulsifier, polymerized phosphate, antioxidant, and amylase may be added as auxiliary materials within a range that does not affect the pH of the alkaline aqueous solution. In addition, seasonings such as salt, soy sauce and sugar may be used for seasoning.

  Next, the rice cooking process will be described. Although the rice cooking method in this invention is not restrict | limited in particular, What is necessary is just to cook rice by normal methods, such as gas type rice cooking, electric rice cooking, IH type rice cooking, and rice cooking by steaming. Moreover, what is necessary is just to adjust the amount of water as needed and to cook rice so that the cooked rice of the texture which has the desired stickiness and hardness after cooking can be obtained. For example, rice can be cooked by adjusting the amount of water as appropriate so that the rice cooking yield is 1.6 to 2.6 (corresponding to 49 to 68% in terms of moisture after cooking). Here, rice cooking yield is the weight ratio of rice after cooking to the weight of rice before cooking.

  In general, in order to obtain cooked rice having an appropriate stickiness and hardness, the cooked rice yield is preferably about 1.8 to 2.4 (corresponding to 53 to 63% in terms of cooked water).

  Next, the neutralization process will be described. The neutralization step is not particularly limited as long as it is a method in which an acidic aqueous solution is evenly distributed over the cooked rice. For example, a method of spraying an acidic aqueous solution, immersing in an acidic aqueous solution, or mixing after adding an acidic aqueous solution to a kettle may be used. Among these, the method of immersion or mixing is preferable.

  Here, the acidic aqueous solution used for neutralization is absorbed by the cooked rice. Therefore, the amount of the acidic aqueous solution needs to be adjusted in accordance with the amount of water added during rice cooking from the relationship with the rice cooking yield. For example, the amount of water added during the rice cooking process may be reduced, and the final rice cooking yield may be achieved with an acidic aqueous solution.

  Finally, the processing process will be described. A processing process is a process of processing the cooked rice after neutralization into processed rice. As a method for processing the processed cooked rice, known methods such as high temperature drying and vacuum freeze drying can be applied.

  Hereinafter, the present invention will be described in more detail based on examples. Moreover, each characteristic of this invention was evaluated with the following method. In the present embodiment, a description will be given by taking pre-treated rice as an example of processed rice.

(PH measurement of cooked rice)
The pH measurement of cooked rice was performed as follows. 90 g of water was added to each 10 g of cooked rice before and after neutralization using anhydrous citric acid, which will be described later, and the cooked rice was ground to create a 10% suspension. The pH of this suspension was measured using a desktop pH meter (F-71) manufactured by HORIBA.

(sensory evaluation)
The restoration property of pregelatinized rice was evaluated as follows. 140 g of water was added to 90 g of pregelatinized rice described in “Examples / Comparative Examples” to be described later, and restored by heating in a microwave oven 500 w for 5 minutes and a half. From the viewpoints of texture, taste and return when pre-alpha rice was restored, it was evaluated in five stages.

<Food texture>
Evaluation 5: Extremely superior to Comparative Example 1 4: Excellent than Comparative Example 1 3: Good than Comparative Example 1 2: Equivalent to Comparative Example 1 1: Inferior to Comparative Example 1

<Taste (taste)>
Evaluation 5: better than Comparative Example 1 4: equivalent to Comparative Example 1 3: inferior to Comparative Example 1 2: considerably inferior to Comparative Example 1: 1: extremely inferior to Comparative Example 1

<Return>
Evaluation 5: Extremely superior to Comparative Example 1 4: Excellent than Comparative Example 1 3: Good than Comparative Example 1 2: Equivalent to Comparative Example 1 1: Inferior to Comparative Example 1

Example 1
1000 g of uruchi polished rice was washed and drained. Next, 150% of water and 1 g of sodium carbonate based on the weight of rice were added and stirred well. It was allowed to stand for 30 minutes as it was and soaked polished rice. The soaked polished white rice was cooked for 15 minutes using a rice cooker (Rinnai gas cooker RR-10KS) and steamed for 20 minutes. As a result, cooked rice with a rice yield of 2.32 (equivalent to 63% moisture after cooking) was obtained.

  Next, what mixed uniformly 14 g of emulsified fats and oils, 3 g of sucrose fatty acid ester, and 0.5 g of anhydrous citric acid with respect to 500 g of water was prepared, added to cooked rice, and water was absorbed while stirring.

  Water-absorbed cooked rice was dried at 80 ° C. in a drying cabinet at a wind speed of 1 m / s for 120 minutes until the water content of the cooked rice reached 6% (weight ratio). And after crushing the dry rice which has been bound, it was passed through a sieve to remove the bound rice and cracked rice, thereby obtaining a pregelatinized rice having a water content of 6%.

(Example 2)
The same as Example 1 except that the amount of anhydrous citric acid was 0.6 g.

(Example 3)
The same as Example 1, except that the amount of anhydrous citric acid was 0.8 g.

(Comparative Example 1)
In Example 1, it is the same as Example 1 except that sodium carbonate aqueous solution and anhydrous citric acid were not added.

(Comparative Example 2)
Example 1 is the same as Example 1 except that citric anhydride is not added.

(Comparative Example 3)
Example 1 is the same as Example 1 except that the amount of anhydrous citric acid is 0.2 g.

(Comparative Example 4)
Example 1 is the same as Example 1 except that the amount of citric anhydride is 1.2 g.

  Table 1 shows the texture, taste, return, and pH of cooked rice in the process of producing pregelatinized rice when the pregelatinized rice in Examples 1 to 3 and Comparative Examples 1 to 4 was restored.

＊：中和処理のない（無水クエン酸を用いない）炊飯米のｐＨについては、括弧書きで記載した。

*: The pH of cooked rice without neutralization treatment (without using anhydrous citric acid) is described in parentheses.

  As shown in Table 1, the pH of cooked rice before neutralization in Examples 1 to 3 was 8.7, whereas the pH of cooked rice after neutralization was 7 to 7.35. From this, it can be seen that even after cooking rice, the cooked rice itself can be neutralized. Moreover, when the food texture, taste, and return of Examples 1 to 3 were evaluated, the same evaluation as Comparative Example 1 in which the taste was a control was obtained. It was evaluated that the texture and return were greatly improved over Comparative Example 1 as a control.

  On the other hand, Comparative Example 2 was an example in which neutralization was not performed, but better results than Comparative Example 1 were obtained with respect to texture and return. However, it was evaluated that the taste was inferior and was inferior to Comparative Example 1. In addition, it is because of the influence of an emulsifier that the pH of cooked rice has changed.

  Comparative Example 3 is an example where neutralization is insufficient. Better results than those of Comparative Example 1 were obtained with respect to texture and return. However, as for Comparative Example 2, as in Comparative Example 2, there was an umami in taste, and the evaluation was inferior to Comparative Example 1.

  Comparative Example 4 is an example in which neutralization becomes excessive. In such a case, a slight improvement in texture was observed compared to Comparative Example 1. On the other hand, no improvement was observed in taste and return. Moreover, since the cooked rice after neutralization is close to acidity, the acidity was slightly tight.

  From the above results, the following can be considered. There is a tendency for the texture and the return to be improved as the pregelatinized rice using cooked rice whose pH after neutralization is close to alkalinity. Moreover, the alpha-ized rice using the cooked rice whose pH after neutralization is around 7 was close to Comparative Example 1 in which the taste was control. This is thought to be because when the rice is cooked under alkaline conditions, the starch of the rice swells and can be cooked softly to the core of the rice. Moreover, it is considered that returning the pH of the cooked rice to near neutrality can eliminate sourness and sashimi while maintaining a softly cooked state. Therefore, in order to improve the restoration property, texture and taste of processed cooked rice, it is considered important to make the pH of the cooked rice itself alkaline once and then return it to the vicinity of neutrality. Therefore, the pH of the rice itself immediately after cooking needs to be alkaline, and in the case where it is neutralized before cooking, it is considered that the effect of the present invention cannot be obtained.

  The processed cooked rice of the present invention is not limited to white rice, and is also effective as cooking rice. For example, the α-rice rice of Example 2 is put in a cup-shaped plastic container for microwave oven, 37.0 g of powdered curry soup, 3.5 g of dried beef, 2.6 g of dried potatoes, and 0.5 g of dried carrots. And mixed. Then, 260 ml of water at 25 ° C. was added and lightly stirred, then covered, cooked in a microwave oven at 500 W for 5 and a half minutes, and taken out of the microwave oven to make instant curry rice.

  When this was eaten and evaluated by five skilled panelists, evaluation was obtained that the texture, taste, and return were the same as in the case of cooking only the pregelatinized rice of Example 2.

Claims (2)

In the method of producing processed cooked rice,
An immersion step of immersing in an alkaline aqueous solution;
A rice cooking step of cooking together with the alkaline aqueous solution;
A neutralization step of neutralizing with an acidic aqueous solution after cooking,
A processing step of processing the cooked rice after neutralization;
Process for producing cooked cooked rice. The method for producing processed cooked rice according to claim 2 , wherein the neutralization step is performed by adding an acidic aqueous solution to cooked rice.