JP4400564B2 - Manufacturing method of dry yuba - Google Patents

Description

  The present invention relates to a method for producing dry yuba.

  Yuba is made from soy milk, just like tofu. When the raw soymilk is heated to such an extent that it does not boil, a film is formed on the surface. “Yuyu” is a piece of this film scooped with bamboo skewers or wire. Among them, the one that is first pulled and entangled with soy milk is called “pumped yuba”, which is particularly excellent in flavor and texture. Next, the soy milk that has been entangled with the yuba is called “raw yuba”, and the yuba that has been naturally dried or hot-air dried is called “dried yuba”.

  Most of the dry yuba is reconstituted or boiled with a seasoning solution and eaten, but the color turns brown, the texture is harder and the flavor is lower than the raw yuba. However, the dried yuba itself has a long shelf life because it has a lower moisture content than the raw yuba, can be stored at room temperature, is easy to handle, and has no restrictions on distribution and sales.

  In order to improve the shelf life of fresh yuba, when yuba alone is sterilized by heating, the yuba solidifies and becomes hard to the touch. If it is frozen and preserved, it will be frozen and denatured, resulting in a firm and stiff texture after thawing. In this way, it is difficult to extend the storage stability while retaining the umami taste of soybeans and the texture of fresh yuba.

To the long-term storage by freezing the possible, adding from 0.1 to 25% of sugars in soy milk to make a raw yuba that prevent freeze denaturation, or carbohydrate to immersion soy milk yuba 0.1 to 25% Some have been added (for example, see Patent Document 1). In the present invention, improvement in storage stability by freezing and improvement in texture after thawing are sought, but there is no mention of dried products.

  A manufacturing method for using dry yuba instead of instant noodles in a cup is described (for example, see Patent Document 2), but the yuba described therein obtains the texture of the instant noodle that is sought. Even if it is possible, it is not possible to obtain a soft and smooth texture with the soybean flavor remaining like raw yuba or pumped yuba. This is because, in order to cut yuba into noodles, yuba with a water content of 55% or more found in the present invention is too soft and difficult to cut finely, and yuba containing a large amount of soy milk will drip soy milk and the workability will deteriorate. .

[References]
(Patent Document 1) Japanese Patent Application Laid-Open No. 2001-057860 (Patent Document 2) Japanese Patent Application Laid-Open No. 10-295111

  The present invention provides a yuba that has a texture, flavor, and color tone of fresh yuba or pumped yuba even in dry yuba that can be distributed at room temperature.

  The present invention is a method for producing dried yuba, characterized by freeze-drying yuba having a moisture content of 55% or more. Specifically, the yuba having a moisture content of 55% or more may be a yuba that has been semi-dried and rehydrated. When the water content of yuba is 60% or more, it is preferable to include a freeze denaturation inhibitor. Moreover, this invention is the dry yuba prepared by these manufacturing methods. Moreover, this invention is an instant food which uses this dry yuba as an ingredient.

  According to the present invention, it is possible to provide a dry yuba that has a long shelf life and can have a texture, color tone and flavor equivalent to that of fresh yuba after reconstitution with water.

  As the soy milk that is the raw material for the yuba production of the present invention, soy milk that is usually used for yuba production can be used. For example, after soaking whole soybeans in water, kure obtained by grinding with about 5 to 8 times the amount of water is heated, and this is filtered to separate okara to obtain soy milk. The solid content concentration of soymilk is not particularly limited, but is generally 5 to 10%.

  Yuba is a film in which a film is formed on the surface of soy milk when heated, and the film is scooped with bamboo skewers or wire. Those that do not dry are called `` raw yuba '', among them, the one that is pulled up first, soy milk entangled is called `` pumped yuba '', and it is said that the flavor and texture are particularly excellent, the moisture is Over 60%. The raw yuba is naturally dried or hot-air dried. Among these, “semi-dry yuba” refers to yuba having a water content of about 30% to 50%.

  Semi-dried yuba has a strong film due to drying, so that the yuba can be easily processed, and can be cut into a thin shape or a desired shape.

  The yuba before freeze-drying (freeze-drying) is preferably a yuba having a moisture content of 55% or more. Alternatively, the semi-dried yuba may be rehydrated to have a water content of 55% or more. Water reconstitution may be carried out with seasoning liquid or soy milk in addition to water. Among them, in particular, by preparing semi-dry yuba together with soy milk to prepare yuba having a water content of 55% or more, yuba having a favorable texture and flavor can be obtained. Moreover, it is preferable to heat at 70-100 degreeC in the ratio of semi-dry yuba and soymilk 1: 1 or more, Preferably it is a ratio of 1:10. If the water content is less than 55%, the yuba can be processed easily and can be cut finely, but when the freeze-dried product is reconstituted, the soft texture of the raw yuba that is desired cannot be obtained. .

  Yuba with a moisture content of 55% or more may be freeze-dried as it is. When this is reconstituted with hot water, a soft and smooth texture like fresh yuba is obtained.

  However, if the water content is 60% or more and soy milk is often attached to yuba and the soy milk freezes and denatures and the texture and flavor are both impaired, add a freeze-modifying agent to the soy milk that makes yuba. It is better to keep it. When the dried yuba is reconstituted with a solution (water, seasoning liquid or soy milk) and the water content is adjusted to 60% or more, a freeze denaturant may be added to the solution.

  Specifically, as a method for preparing yuba that has been treated to prevent freeze denaturation of 60% or more, a method in which 5 to 30% of the freezing denaturant is dissolved in soy milk that makes yuba and the yuba is pulled up, or the yuba that has been pulled up is frozen and denatured. In the case of using a method of immersing in a 5 to 10% solution containing an inhibitor, or a yuba that has been cut to a moisture content of 55% or more after cutting a yuba of 55% or less, a freeze denaturation inhibitor is added to the soy milk used for the adjustment. Examples thereof include a method of adding 10%.

  As the freeze denaturation inhibitor of the present invention, for example, known substances such as sugars, starches, and transglutaminase, which are used for freeze denaturation prevention of frozen tofu, can be used.

  The saccharide to be added is not particularly limited, but it is preferable to use one or more selected from the group consisting of monosaccharides, oligosaccharides, oligosaccharides and sugar alcohols. As monosaccharides, glucose, fructose, xylose, mannose, galactose, etc., as oligosaccharides, maltose, sugar, lactose, trehalose, etc., as oligosaccharides, as maltooligosaccharides, isomaltoligosaccharides, fructooligosaccharides, galactooligosaccharides, sugars, etc. Examples of alcohols include sorbitol, maltitol, erythritol, palatinit, lactitol, reduced starch saccharified product, and the like. The starch may be potato starch, corn starch, wheat starch, tapioca starch, or a modified product thereof, for example, pregelatinized starch. Transglutaminase may be used as it is, or a transglutaminase preparation containing a food material such as starch may be used.

  By adding a known antioxidant to the soy milk that makes yuba or the yuba that has been pulled up, deterioration of flavor and color tone can be suppressed and the storage period at room temperature can be extended.

  The yuba may be colored depending on the application. For example, when the noodles eaten together are whitish and the yuba is not conspicuous, the soy milk that makes yuba or the soy milk that returns yuba with a moisture content of less than 60% can be added with a pigment to make it pale yellow.

  The yuba of the present invention can be mixed with other ingredients in advance before drying. Ingredients include vegetables, seaweeds, and seafood.

  Drying of the yuba of the present invention is limited to freeze drying, and other natural drying, microwave drying, fly drying, and hot air drying cannot obtain the required quality after reconstitution with hot water. Freeze-drying is a freeze-drying method in which food is dried by sublimation and removal of moisture by keeping it at a low temperature in a vacuum. The freeze-drying technique is a known processing method described in the prior art relating to tofu (see, for example, JP-A-59-28448 and JP-A-60-52792). In the case of Yuba of the present invention, the preferred conditions for this treatment method are that pre-freezing should be quick freezing at −30 to −40 ° C., and the shelf heating temperature of FD treatment is preferably 30 to 60 ° C. in order to maintain the flavor of Yuba. The moisture sublimation time is preferably 14 to 20 hours.

  The freeze-dried product can be reconstituted with hot water or with a seasoning liquid, but in a liquid containing a large amount of salt, the texture may be tightly squeezed, so hot water or soy milk is preferred to obtain a softer yuba. .

  The dried yuba obtained as described above can have a smooth texture and a rich flavor of soybeans as if it had been pumped up even after rehydration.

  Therefore, the dried yuba of the present invention is excellent as an ingredient for various instant foods such as instant noodles, instant soups, instant miso soups and the like.

  Examples of the present invention will be described below, but the technical scope of the present invention is not limited by these examples.

(Production Example 1)
Retort pouch (material: NY15 / LLDP85) filled with 20 g of cut 50 mm square yuba dried with hot air from raw yuba and 80 g of 8BX soymilk prepared by the usual method with 8% maltose added Vacuum sealed. This was sterilized by heating in a steamer set at 90 ° C. for 30 minutes, cooled with running water, and then frozen in a freezer at −35 ° C. The moisture at this time was 62%.

(Production Example 2)
7BX soymilk in which 10% of maltose was dissolved was indirectly heated at 98 ° C., and the yuba pumped up with chopsticks was placed in an aluminum 50 mm square container and frozen. At this time, the water content of Yuba was 62%.

(Production Example 3)
7 BX soymilk was indirectly heated at 98 ° C., pulled up by bamboo skewers, and cut off excess soymilk to prepare a yuba with a water content of 58%. The yuba was cut off from the bamboo skewers and frozen.

(Production Example 4)
The raw yuba was dried with hot air to freeze the yuba with a moisture content of 50%.

Example 1
The yuba prepared in Production Example 1 was naturally thawed, placed in an aluminum 50 mm square vessel, and freeze-dried.

(Example 2)
The yuba prepared in Production Example 2 was freeze-dried.

(Example 3)
The yuba prepared in Production Example 3 was freeze-dried.

(Comparative Example 1)
The yuba prepared in Production Example 1 was naturally thawed, placed in a 50 mm square container made of aluminum, and dried with hot air in a 60 ° C. drying room.

(Comparative Example 2)
The yuba prepared in Production Example 2 was dried with hot air in a drying room at 60 ° C.

(Comparative Example 3)
The yuba prepared in Production Example 3 was dried with hot air in a drying room at 60 ° C.

(Comparative Example 4)
The yuba prepared in Production Example 1 was naturally thawed, placed in an aluminum 50 mm square vessel, and dried at room temperature.

(Comparative Example 5)
The yuba prepared in Production Example 2 was dried at room temperature.

(Comparative Example 6)
The yuba prepared in Production Example 3 was dried at room temperature.

(Comparative Example 7)
The yuba prepared in Production Example 4 was freeze-dried.

(Food texture, flavor evaluation method)
When eating, the dried yuba was reconstituted with noodles for 3 minutes instead of the ingredients for instant udon sold in general.
As for the evaluation type, 5 points were good (pumped yuba style), 4 points (raw yuba style), 3 points were normal, 2 and 1 were not preferable, and 4 points or more were regarded as having commercial value. The panelists were evaluated by five people. However,-was poor in hot water return and could not be evaluated.

(Table 1) Texture, flavor, color tone, evaluation results

<Evaluation of texture, flavor and color tone by yuba drying method>
Example 1
A yuba with a color similar to that of pumped yuba, a smooth and soft texture, and a delicious taste was obtained.
(Example 2)
A yuba with a color similar to that of pumped yuba, a smooth and soft texture, and a delicious taste was obtained.
(Example 3)
A yuba with a color similar to that of fresh yuba, a smooth texture and a delicious taste was obtained.
(Comparative Example 1)
Since the soy milk around the yuba was solidified by heat and dried and hardened, the hot water return was very bad. The texture is not as smooth as raw yuba, and there is little soy flavor left. The color was drunk.
(Comparative Example 2)
Since the soy milk around the yuba was solidified by heat and dried and hardened, the hot water return was very bad. The texture is not as smooth as raw yuba, and there is little soy flavor left. The color was drunk.
(Comparative Example 3)
The hot water return is a little bad, the smooth texture of raw yuba is not obtained, and the soybean flavor remains very little. The color was drunk.
(Comparative Example 4)
The texture and color change is slower than hot air drying, but the soy milk around the yuba coagulates due to heat, and it becomes dry and hard. The texture is not as smooth as raw yuba, and the soy flavor is weak. The color was somewhat drastic.
(Comparative Example 5)
The texture and color change is slower than hot air drying, but the soy milk around the yuba coagulates due to heat, and it becomes dry and hard. The texture is not as smooth as raw yuba, and the soy flavor is weak. The color was somewhat drastic.
(Comparative Example 6)
Although the texture and color change are moderate compared to hot air drying, the texture is not as smooth as raw yuba and the soybean flavor is also faint. The color was somewhat drastic.
(Comparative Example 7)
It did not reach the color tone and smooth texture of fresh yuba.
From the above results, hot air dried or naturally dried yuba had a great difference from the quality before drying after reconstitution with hot water, and the desired texture, flavor and color tone could not be obtained. In freeze drying, it was found that either the yuba with a moisture content of 55% or more or the yuba with moisture content of 60% or more, which had been prevented from freezing and denaturation, had the same texture, taste and color tone as before drying.

Claims (4)

A method for producing a dried yuba, characterized in that a semi-dried yuba having a moisture content of 30 to 50% is rehydrated to obtain a moisture content of 60 % or more, and the yuba containing a freeze-denaturation inhibitor is freeze-dried. The method for producing dried yuba according to claim 1, wherein the water reconstitution is performed with soy milk. A dry yuba prepared by the production method according to claim 1. An instant food comprising the dried yuba according to claim 3 as an ingredient.