Cooked rice for freeze-drying, method for producing cooked rice for freeze-drying, freeze-dried rice, and freeze-dried processed food

Abstract

To provide cooked rice for freeze-drying having excellent grain mouthfeel, grain separation, and fluffiness, as well as freeze-dried rice and freeze-dried processed food using the cooked rice.SOLUTION: Cooked rice for freeze-drying of the present invention is prepared by cooking 100 pts.mass of raw rice having an amylose content of 19.2 mass% or less and a protein content of 7.5 mass% or less (dry basis), followed by adjustment to 210 to 290 pts.mass through water-washing adjustment and draining steps. Freeze-dried rice or freeze-dried processed food of the present invention is prepared by freeze-drying the cooked rice for freeze-drying, or by adding a seasoning liquid thereto.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to cooked rice for freeze-drying, a method for producing cooked rice for freeze-drying, freeze-dried rice, and freeze-dried processed foods. [Background technology]

[0002] Freeze-dried rice, which can be reconstituted into cooked rice by pouring hot water over it, has been commercially available for some time as instant cooked rice or emergency cooked rice. In order to produce freeze-dried rice, it is common to obtain cooked rice by cooking rice in a pot or other method, freeze the obtained cooked rice, and then dry it under vacuum (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6917034 Summary of the Invention [Problem to be solved by the invention]

[0004] However, with such conventional methods, it was difficult to obtain cooked rice that retained its texture over time and had a good flavor. In particular, when trying to obtain a processed food by adding seasoning liquid, the permeability and water retention of the seasoning liquid were insufficient, and there remained a major problem in obtaining a tasty freeze-dried processed food.

[0005] The present invention aims to provide cooked rice for freeze-drying that maintains the rice grain texture, grain standing, and plumpness of rice, and to provide freeze-dried rice and freeze-dried processed foods using the cooked rice. [Means for solving the problem]

[0006] In order to achieve the above object, the present invention provides: The present invention relates to cooked rice for freeze-drying, which is obtained by cooking 100 parts by mass of raw rice having an amylose content of 19.2% by mass or less and a protein content of 7.5% by mass or less (dry basis), and then adjusting the rice to 210 to 290 parts by mass through a washing / adjusting and draining process.

[0007] The present invention also provides a method for producing a semiconductor device comprising the steps of: For 100 parts by mass of raw rice with amylose content of 19.2% by mass or less and protein content of 7.5% by mass or less (dry basis), the jelly strength is 100g / cm 2 The present invention relates to cooked rice for freeze-drying, which is prepared by adding the following agar or agar solution at any timing while cooking the rice, and then adjusting the weight to 210 to 290 parts by weight through a water-washing and / or draining process.

[0008] The present invention also provides a method for producing a semiconductor device comprising the steps of: After cooking 100 parts by mass of raw rice with an amylose content of 19.2% by mass or less and a protein content of 7.5% by mass or less (dry basis), the jelly strength is 100g / cm 2 The present invention relates to cooked rice for freeze-drying, to which the following agar or agar solution has been added and which has been adjusted to 210 to 290 parts by mass by a water washing / adjusting and / or draining step.

[0009] The present invention also provides a method for producing a semiconductor device comprising the steps of: For 100 parts by mass of raw rice with amylose content of 19.2% by mass or less and protein content of 7.5% by mass or less (dry basis), the jelly strength is 100g / cm 2 The present invention relates to cooked rice for freeze-drying, which is prepared by adding the following agar or agar solution, cooking the rice, and then adjusting the weight of the rice to 210 to 290 parts by mass through a water-washing and / or draining process.

[0010] The present invention also provides a method for producing a semiconductor device comprising the steps of: 100 parts by mass of raw rice having an amylose content of 19.2% by mass or less and a protein content of 7.5% by mass or less (dry basis) is cooked, adjusted to 210 to 290 parts by mass through a washing and / or draining process, and then made into a jelly having a strength of 100 g / cm 2 The present invention relates to cooked rice for freeze-drying, to which the following agar or agar solution has been added:

[0011] The present invention also provides a method for producing a semiconductor device comprising the steps of: Raw rice with amylose content of 19.2% by mass or less and protein content of 7.5% by mass or less (dry basis) and jelly strength of 10 to 100 g / cm 2 The present invention relates to cooked rice for freeze-drying, which is made from the above-mentioned agar or agar solution and water, and which is cooked with 50 to 67% by mass of water added based on the total mass, and then washed, adjusted, and drained.

[0012] Furthermore, the present invention provides a method for producing a The present invention relates to freeze-dried rice obtained by freeze-drying the cooked rice.

[0013] Furthermore, the present invention provides a method for producing a This relates to freeze-dried rice in which the time it takes to pass through the maximum ice crystal formation zone during freeze-drying is 2 hours or more.

[0014] Furthermore, the present invention provides a method for producing a This relates to freeze-dried rice having 10 or more residual pores with a Feret's diameter of 100 μm or more per grain of freeze-dried rice.

[0015] Furthermore, the present invention provides a method for producing a The present invention relates to a method for producing cooked rice for freeze-drying, in which the rice is washed with 300 to 700 parts by mass of water, assuming that the water used during cooking is 100 parts by mass.

[0016] Furthermore, the present invention provides a method for producing a The freeze-dried processed food is obtained by adding a seasoning liquid to the cooked rice to be freeze-dried, adjusting the seasoning, and then freeze-drying the cooked rice.

[0017] Furthermore, the present invention provides a method for producing a This relates to cooked rice for freeze-drying, which has a passage time through the maximum ice crystal formation zone during freeze-drying of 2 hours or more.

[0018] Furthermore, the present invention provides a method for producing a The present invention relates to cooked rice for freeze-drying, in which each freeze-dried grain of rice has 10 or more residual pores with a Feret's diameter of 100 μm or more. Effect of the Invention

[0019] According to the present invention, it is possible to provide cooked rice for freeze-drying that maintains the rice grain texture, graininess, and plumpness of rice, and freeze-dried rice or freeze-dried processed food using the cooked rice. [Brief description of the drawings]

[0020] [Figure 1] FIG. 1 is a diagram showing an example of a flowchart for producing cooked rice or freeze-dried rice for freeze-drying according to the present invention. [Diagram 2] FIG. 1 is a diagram showing an example of a flowchart for producing cooked rice or freeze-dried rice for freeze-drying according to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] Hereinafter, the present invention will be described based on an embodiment. Fig. 1 is a diagram showing an example of a flowchart of a method for producing cooked rice for freeze-drying or freeze-dried rice. Note that the "cooking rice" described in the following description is not limited to a specific method such as electric rice cooker cooking, gas rice cooker cooking, kneader cooking, steam cooking, batch cooking, continuous cooking, etc. However, in this embodiment, the procedure of cooking rice in an electric rice cooker and adding agar before cooking will be described as an example. As shown in Figure 1, first, raw rice with an amylose content of 19.2% by mass or less and a protein content of 7.5% by mass (dry basis) or less is prepared (S1). Generally, amylose gives a dry texture, and protein present around starch physically prevents the swelling and gelatinization of starch, resulting in a decrease in physical properties. Therefore, if the amylose content exceeds 19.2% by mass or the protein content exceeds 7.5% by mass (dry basis), when the rice is freeze-dried and rehydrated in hot water to produce cooked rice, the cooked rice becomes hard and has a poor flavor.

[0022] The raw rice is not particularly limited to a particular variety as long as it has an amylose content of 19.2% by mass or less and a protein content of 7.5% by mass or less (dry basis), and may be polished rice or non-rinsed rice.

[0023] The lower limit of the amylose content is not particularly limited, but may be, for example, 10% by mass. Similarly, the lower limit of the protein content is not particularly limited, but may be, for example, 5.5% by mass (dry basis).

[0024] Next, the raw rice is washed and drained in the usual way (S2), and then water is added to the desired amount of water and powdered agar is added, and then the rice is soaked in water for, for example, one hour (S3). In this embodiment, powdered agar is used, but it does not necessarily have to be in powder form, and it may be in granular form or liquid form dissolved in any solution in advance.

[0025] The rice is then cooked (S4). The weight average molecular weight of the agar is about 30,000 to 100,000, and the jelly strength is 10 g / cm 2 From 100g / cm 2 It is preferable to set the thickness to 100 g / cm 2 It is necessary that the agar content is equal to or less than 0.2% by mass. Jelly strength can be measured by the Nihon Kansui method. By adding agar, the surface of the rice grain is coated. This prevents the components from leaking out and maintains the texture. It also provides resistance to freezing and drying. If the coating is too thin, the effect is not obtained, while if it is too thick, it hinders the reconstitution. Taking into consideration coloring and gelation, the agar content is preferably 0.2 to 1.0% by mass relative to the total mass.

[0026] If the jelly strength of the agar exceeds this range, it takes a long time to rehydrate, and problems occur such as the formation of lumps after rehydration, the plumpness of rice grains not being reproduced after rehydration, and the texture after the passage of time being poor.

[0027] Furthermore, if the amount of water added is small, the core of the rice grain may remain due to improper cooking or the cooked rice may be too hard, resulting in a poor texture after freeze-drying. Conversely, if the amount of water added is large, the cooked rice may be soft and the rice grain texture may not be felt even after freeze-drying, resulting in a poor texture. For these reasons, it is preferable that the water content (water blending ratio) be 50 to 67% by mass relative to the total mass.

[0028] Next, the cooked rice is washed with water (S5). The cooked rice can be washed by exposing it to a fixed amount of water. Here, washing with water in a fixed amount of water (dilution) is used, rather than washing with running water. As an example, the cooked rice is placed in a colander, and stirred at a fixed speed for, for example, 3 minutes in 300 to 700 parts by mass of water, assuming that the water used during cooking is 100 parts by mass. The temperature of the water at this time is preferably 35°C or less.

[0029] The purpose of washing cooked rice in a fixed amount of water (dilution) is to optimize the concentrations of amylose and protein on the surface of the cooked rice, as well as the agar added during cooking. The rice grains are made single grains, and a good rice texture is reproduced when rehydrated in hot water after freeze-drying. Good rice texture here means that the rice grains maintain a moderate stickiness and hardness, and do not appear to have collapsed. Washing in a fixed amount of water (dilution) also has the effect of cooling the rice from preheating.

[0030] After washing, the water is drained (S6) so that the total mass after washing is 117 to 128% by mass relative to the total mass before washing, for example.

[0031] Next, dispensing is performed (S7). Dispensing is preferably performed within 60 minutes after the cooked rice is washed. Dispensing is performed, for example, by weighing 60 g onto a tray. When producing processed foods from the cooked rice, it is preferable to add and mix seasoning liquid during this dispensing process. The amount of seasoning liquid can be, for example, 40 g.

[0032] In order to provide shape retention, it is preferable to use a mixture of agar or potato starch and dextrin in the seasoning liquid.

[0033] Next, the dispensed cooked rice or processed food is frozen (S8). The freezing method is not particularly limited as long as it is a method that allows ice crystals to grow large, but it is preferable that slow freezing is performed first, followed by rapid freezing. The purpose of slow freezing is to allow ice crystals in the cooked rice to grow large, thereby imparting good restorability. It is preferable to pass through 0 to -5°C, which is generally considered to be the maximum ice crystal formation zone, over a period of 2 hours or more.

[0034] Subsequent quick freezing is performed at -30°C or below until the core temperature reaches -18°C or below.

[0035] By the freezing operation as described above, it is possible to produce cooked rice for freeze-drying in which there are 10 or more remaining holes with a Feret diameter of 100 μm or more per grain after freeze-drying, and it is possible to provide cooked rice for freeze-drying that maintains the rice grain texture, graininess, and plumpness of the rice, as well as freeze-dried rice and freeze-dried processed foods using the cooked rice. The Feret diameter is measured and defined as the distance between two parallel lines when the remaining holes are sandwiched between them.

[0036] Next, the frozen cooked rice or processed food is vacuum dried in the usual way (S9). Through the above process, the rice retains its grain texture, firmness, and plumpness.

[0037] The method for producing cooked rice or freeze-dried rice for freeze-drying of the present invention may be as follows: Figure 2 is a flowchart showing the method for producing cooked rice or freeze-dried rice for freeze-drying described below.

[0038] The cooked rice for freeze-drying is adjusted to 210 to 290 parts by mass by cooking 100 parts by mass of raw material rice, and then passing the cooked rice through the above-mentioned steps of rinsing (S5) and draining (S6). It is preferable that the cooked rice obtained by cooking 100 parts by mass of raw material rice is adjusted to 180 to 230 parts by mass.

[0039] The raw rice to be cooked must have an amylose content of 19.2% by mass or less and a protein content of 7.5% by mass or less on a dry basis, and must have a jelly strength of 100g / cm before cooking. 2 Add the following agar. However, if the agar is in powder or granular form, it is preferable to add it before cooking the rice because it dissolves in water when heated. However, if you are using an agar solution dissolved in hot water, for example, it is preferable to add it before draining the water (S6).

[0040] The cooked rice adjusted to 210 to 290 parts by mass by washing (S5) and draining (S6) is preferably dispensed (S7) within 60 minutes after draining (S6) is completed. Dispensing is performed, for example, by weighing 45 g onto a tray. When producing processed foods from the cooked rice, it is preferable to add and mix seasoning liquid during this dispensing process. In this case, the amount of seasoning liquid is preferably 54 g.

[0041] When freezing the portioned cooked rice or processed food (S8), it is preferable to first slowly freeze the rice or processed food, and then rapidly freeze the rice. Slow freezing is preferably performed by passing the rice through a temperature range of 0 to -5°C, which is generally considered to be the maximum ice crystal formation zone, over a period of 2 hours, which allows the rice or processed food to have good restorability. Rapid freezing is performed by rapidly freezing the rice or processed food at a temperature of -30°C or below until the core temperature reaches -18°C or below.

[0042] The frozen cooked rice or processed food is vacuum dried in a conventional manner (S9). Through the above steps, cooked rice for freeze-drying or freeze-dried processed food is produced.

[0043] As described above, by adjusting the mass parts of the cooked rice after draining (S6) to 210 to 290 per 100 parts by mass of raw material rice for freeze-drying, a product with good rehydration properties and texture after rehydration can be produced.

[0044] In view of the above embodiments, the present application also includes the following inventions. [1] Cooked rice for freeze-drying, which is obtained by cooking 100 parts by mass of raw rice having an amylose content of 19.2% by mass or less and a protein content of 7.5% by mass or less (dry basis), and then adjusting the rice to 210 to 290 parts by mass through a water washing / adjusting and / or draining process. [2] For 100 parts by mass of raw rice with an amylose content of 19.2% by mass or less and a protein content of 7.5% by mass or less (dry basis), the jelly strength is 100g / cm 2 Cooked rice for freeze-drying is prepared by adding the following agar or agar solution at any timing while cooking the rice, and then adjusting the weight to 210 to 290 parts by weight through a water washing and / or draining process. [3] After cooking 100 parts by mass of raw rice having an amylose content of 19.2% by mass or less and a protein content of 7.5% by mass or less (dry basis), the jelly strength is 100g / cm 2 Cooked rice for freeze-drying, to which the following agar or agar solution has been added and the rice has been adjusted to 210 to 290 parts by mass by a water washing / adjusting and / or draining step. [4] For 100 parts by mass of raw rice having an amylose content of 19.2% by mass or less and a protein content of 7.5% by mass or less (dry basis), the jelly strength is 100g / cm 2 Cooked rice for freeze-drying, which is prepared by adding the following agar or agar solution, cooking the rice, and then adjusting the weight to 210 to 290 parts by weight through a water washing and / or draining process. [5] 100 parts by mass of raw rice having an amylose content of 19.2% by mass or less and a protein content of 7.5% by mass or less (dry basis) is cooked, adjusted to 210 to 290 parts by mass through a washing and / or draining process, and then the jelly strength is 100 g / cm 2 2. Cooked rice for freeze-drying, comprising the following agar or agar solution added thereto: [6] Raw rice with an amylose content of 19.2% by mass or less and a protein content of 7.5% by mass or less (dry basis) and a jelly strength of 10 to 100 g / cm 2 This cooked rice is made from the above-mentioned agar or agar solution and water, and is cooked with 50 to 67% by mass of water added based on the total mass, and then washed, adjusted, and drained for freeze-drying. [7] Freeze-dried rice obtained by freeze-drying the cooked rice according to any one of [1] to [6]. [8] The freeze-dried rice according to [7], wherein the time it takes to pass through the maximum ice crystal formation zone during freeze-drying is 2 hours or longer. [9] Freeze-dried rice according to [7] or [8], in which each freeze-dried rice grain has 10 or more residual pores with a Feret diameter of 100 μm or more.

[10] A method for producing cooked rice for freeze-drying according to any one of [1] to [6], comprising washing the rice with 300 to 700 parts by mass of water, assuming that the water used in cooking is 100 parts by mass.

[11] A freeze-dried processed food, obtained by adding a seasoning liquid to the cooked rice for freeze-drying according to any one of [1] to [6], adjusting the seasoning, and then freeze-drying the cooked rice.

[12] The cooked rice for freeze-drying according to any one of [1] to [6], wherein the time it takes to pass through the maximum ice crystal formation zone during freeze-drying is 2 hours or longer.

[13] Cooked rice for freeze-drying according to any one of [1] to [6] or

[12] , wherein each freeze-dried rice grain has 10 or more residual pores with a Feret diameter of 100 μm or more. EXAMPLES

[0045] Cooked rice and processed foods were produced using the raw rice, agar, and water shown in Table 1.

[0046] [Table 1]

[0047] As is clear from Table 1, by using rice, agar, and water that satisfy the requirements of the present invention as raw materials and cooking the rice so that the moisture content satisfies the moisture content of the present invention, it is possible to provide cooked rice for freeze-drying that has excellent rice grain texture, graininess, and plumpness, and freeze-dried rice or freeze-dried processed foods using this cooked rice.

[0048] In addition, cooked rice and processed foods were produced using the raw rice, agar, and water shown in Table 2.

[0049] [Table 2]

[0050] As is clear from Table 2, when the amount of drained cooked rice is adjusted to 210 to 290 parts by mass per 100 parts by mass of raw rice, it is possible to provide cooked rice for freeze-drying that has good rehydration properties and has excellent rice grain texture, graininess, and plumpness after rehydration, and freeze-dried rice or freeze-dried processed foods using this cooked rice.

[0051] Although several embodiments of the present invention have been described above, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included in the scope and spirit of the invention, and are included in the scope of the invention and its equivalents described in the claims.

Claims

1. The cooked rice for freeze-drying is obtained by cooking 100 parts by mass of raw material rice having an amylose content of 19.2% by mass or less and a protein content of 7.5% by mass or less (dry basis), and then adjusting the amount to 210 to 290 parts by mass through a water washing / adjusting and / or draining process.

2. For 100 parts by mass of raw rice having an amylose content of 19.2% by mass or less and a protein content of 7.5% by mass or less (dry basis), the jelly strength is 100 g / cm ２ This cooked rice for freeze-drying is prepared by adding the following agar or agar solution at any timing while cooking the rice, and then adjusting the weight of the rice to 210 to 290 parts by weight through a water washing and / or draining process.

3. After cooking 100 parts by mass of raw rice having an amylose content of 19.2% by mass or less and a protein content of 7.5% by mass or less (dry basis), the jelly strength is 100 g / cm ２ Cooked rice for freeze-drying, which is obtained by adding the following agar or agar solution and adjusting the amount to 210 to 290 parts by weight through a water washing / adjusting and / or draining process.

4. For 100 parts by mass of raw rice with an amylose content of 19.2% by mass or less and a protein content of 7.5% by mass or less (dry basis), the jelly strength is 100 g / cm ２ The cooked rice for freeze-drying is prepared by adding the following agar or agar solution, cooking the rice, and then adjusting the weight of the rice to 210 to 290 parts by weight through a water washing and / or draining process.

5. 100 parts by mass of raw rice having an amylose content of 19.2% by mass or less and a protein content of 7.5% by mass or less (dry basis) is boiled, adjusted to 210 to 290 parts by mass by a washing and / or draining process, and then made into a jelly having a strength of 100 g / cm ２ 2. Cooked rice for freeze-drying, comprising the following agar or agar solution added thereto:

6. Raw material rice with amylose content of 19.2% by mass or less and protein content of 7.5% by mass or less (dry basis) and jelly strength of 10 to 100 g / cm ２ This cooked rice is made from the above-mentioned agar or agar solution and water as raw materials, and is cooked with 50 to 67% by mass of water added based on the total mass, and then washed, adjusted, and drained for freeze-drying.

7. Freeze-dried rice obtained by freeze-drying the cooked rice according to any one of claims 1 to 6.

8. 8. The freeze-dried rice according to claim 7, wherein the time required to pass through the maximum ice crystal formation zone during freeze-drying is 2 hours or more.

9. 9. The freeze-dried rice according to claim 7 or 8, wherein each freeze-dried grain of rice has 10 or more residual pores having a Feret's diameter of 100 μm or more.

10. 7. The method for producing cooked rice for freeze-drying according to any one of claims 1 to 6, wherein the cooked rice is washed with 300 to 700 parts by mass of water, assuming that the water used in cooking is 100 parts by mass.

11. A freeze-dried processed food, which is obtained by adding a seasoning liquid to the cooked rice for freeze-drying according to any one of claims 1 to 6 to adjust the seasoning, and then freeze-drying the cooked rice.

12. The cooked rice for freeze-drying according to any one of claims 1 to 6, wherein the time it takes to pass through the maximum ice crystal formation zone during freeze-drying is 2 hours or more.

13. The cooked rice for freeze-drying according to any one of claims 1 to 6 or claim 12, wherein each freeze-dried rice grain has 10 or more residual pores having a Feret's diameter of 100 µm or more.

Images