WO2012153935A2 - Silken tofu manufactured by process including gelatinization reaction of starch - Google Patents

Abstract

The object of the present invention is to provide a method for vacuum freeze-drying a silken tofu without a pre-freezing step, so as to provide a method for drying the silken tofu which can almost completely recover the flavor and texture prior to the drying. Also, the object of the present invention is to provide a method for manufacturing the silken tofu, comprising a step of adding starch to soy milk, and a step of heating for gelatinizing the starch, so as to provide the silken tofu having better physical properties, such as the hardness of the tofu, and a method for manufacturing same. In addition, the object of the present invention is to provide a method for mixing to evenly disperse the starch in the soy milk by using the starch in a starch dispersion liquid form, during a step of mixing the soy milk and the starch in the process of manufacturing a tofu. Furthermore, the object of the present invention is to provide a method for manufacturing the tofu, in which the starch is added and same is gelatinized to provide an appropriate method for manufacturing a silken tofu for drying, and vacuum freeze-drying the silken tofu for drying so as to provide the method for manufacturing the dried silken tofu.

Description

Soft tofu prepared by a process involving gelatinization of starch

The present invention relates to a soft tofu with starch added, and the starch added to the soft tofu undergoes gelatinization reaction during the manufacturing process of tofu, and thus has higher strength and elasticity than conventional soft tofu in physical properties such as hardness of the tofu. It is about high quality tofu.

Tofu is a food rich in minerals and protein, including calcium, and is frequently eaten in a variety of dishes due to its light taste and soft texture. However, tofu is rich in moisture and nutrients, and not only is prone to decay, but also has a disadvantage in that storage and distribution are difficult because the strength of tissues is reduced. Therefore, a method of drying the tofu has been proposed as a method for solving the storage and portability of the tofu at the same time.

As a technique related to the method of drying the tofu, Korean Patent Publication No. 2000-53766 dry tofu and a method of manufacturing the same to put the tofu in a vacuum dryer to decompress and then to dry the tofu for 18-20 hours at a temperature of 60 ℃ The method for drying the tofu has been proposed, and the tofu is placed in a freezer and subjected to pre-cooling for about 1 hour until immediately before freezing, that is, until a freezing phase occurs on the surface of the tofu. Put the dried tofu in a vacuum freeze dryer and depressurize it so that the temperature of the tofu reaches 40 ° C., and then vacuum freeze the step, which is not only cumbersome and complicated, but also takes a long time and denatures the protein. The taste and aroma of tofu are deformed so that the taste of fresh tofu cannot be fully restored when the tofu is restored. Since tissue is destroyed there is a limit not to revive the texture of tofu.

An object of the present invention is to provide a method of drying a tofu that can restore the taste and texture of the state before drying by providing a method of vacuum freezing the tofu to minimize the denaturation of protein in the tofu without preliminary freezing process. do.

In addition, the present invention provides a method for producing a soft tofu comprising the step of adding starch to soy milk and heating the starch in the production of soft tofu, compared to conventional soft tofu in the physical properties such as hardness of the tofu An object of the present invention is to provide a high-quality soft tofu and a method for producing the same, which have high strength and elasticity.

In addition, an object of the present invention is to provide a stirring method for uniformly dispersing starch in soy milk by using starch in the form of a starch dispersion liquid during the step of stirring the soymilk and starch during the manufacturing process of tofu.

In addition, the present invention provides a method for producing a dried tofu suitable for adding dried starch and gelatinizing it to dry dried tofu in the production of tofu and vacuum freeze-drying such dried tofu to prepare a dried tofu. The purpose.

According to one embodiment of the present invention, there is provided a method for producing soft tofu comprising the steps of adding starch to soymilk and heating the starch in a method for producing soft tofu.

According to one embodiment of the present invention, the starch added to the soft tofu undergoes a gelatinization reaction during the manufacturing process of the tofu, resulting in higher strength and elasticity than the conventional soft tofu in physical properties such as hardness of the tofu. Is provided.

According to one embodiment of the present invention, a method of stirring soymilk and starch in the manufacturing process of tofu provides a stirring method for uniformly dispersing starch in soymilk by using starch in the form of a starch dispersion.

According to an embodiment of the present invention, in the method of drying the tofu to provide a method for drying the tofu to provide a method of vacuum freeze drying the tofu without preliminary freezing process to restore the taste and texture of the state before drying as it is .

The following specific examples are merely examples of the present invention, and the contents of the present invention should not be construed as being limited to the following specific examples.

Specifically, the present invention relates to a method for manufacturing dried tofu other than the conventional method for drying the dried tofu to restore the texture similar to the original after the restoration.

The present invention is a manufacturing process of soy milk, a step of adding dilution water, modified starch, antioxidant and coagulant to soy milk, and then stirring it, packaging the soy milk mixture in a soft tofu pouch, heating the packaged soft tofu, solidified soft tofu It may include a step of cooling the cooled tofu tofu, a step of freezing the cut tofu vacuum freezing process and a freeze drying process of the frozen tofu.

The present invention is a soft tofu with higher quality in physical properties such as hardness of tofu, which is not only excellent for use as a dry tofu for producing dried tofu, but also excellent in texture as it is without making it as dry tofu. In order to provide a soft tofu, during the tofu manufacturing process, a step of adding starch to the soymilk and gelatinizing it. The starch is preferably a modified starch, for example, a modified starch such as tapioca modified starch, rice modified starch, sweet potato modified starch, potato modified starch, corn modified starch, more preferably using a tapioca modified starch. The starch is preferably added to 0.1 to 3% by weight, more preferably 1% by weight based on the total weight of the soy milk mixture.

When the starch is mixed with soymilk, the starch and the dilution water are firstly stirred in a starch dispersion form using a known homomixer in order to uniformly disperse the starch in the soymilk, and then it is soaked with soymilk. It is preferred to put it in a tank and proceed with the second stirring step. In the first stirring step, an antioxidant may be additionally added and stirred.

In the coagulant added to the second agitated soymilk mixture, it is preferable not to use glutenol deltalactone (GDL) which decomposes the functional groups of starch and hinders the action of starch, more preferably a mixed coagulant not containing GDL. It is preferable to use magnesium chloride or prepared water as a coagulant, and most preferably calcium sulfate as a coagulant.

In heating the secondary stirred soymilk mixture, it is preferable to induce a gelatinization reaction of starch by heating to a temperature above the gelatinization temperature of the starch added to the soymilk. In one embodiment of the present specification, when the starch added to the soy milk is tapioca modified starch, considering that the gelatinization temperature is 70 to 75 ℃, the product temperature of the tofu is about 80 to 100 ℃ or more, preferably 83 ℃ or more To this end, the temperature of the heating bath is heated to about 80 to 100 ° C, preferably 86 ° C or more, and 40 minutes or more, preferably 1 hour or more, so that the starch is gelatinized. It is preferable to make the said heating process into hot water treatment.

The composition of the soft tofu prepared by the above method is preferably 9 to 12 brix soymilk, more preferably 10.5 brix soymilk, preferably 0.1 to 3 wt%, more preferably starch based on the total weight of the soymilk. It may preferably comprise 1% by weight, preferably 0.1 to 1% by weight, more preferably 0.3% by weight, and additionally 0.01 to 1% by weight, more preferably 0.15% by weight of the antioxidant It may further comprise.

The soft tofu prepared by the above method provides a harder, more firm texture of the tofu in the physical properties of the tofu, such as hardness, gumminess, chewiness, and the like of the conventional tofu.

Specifically, as in one embodiment (Comparative Test Examples 2-1, 3-2) of the present specification, the soft tofu prepared according to the above-described manufacturing method was subjected to physical property analyzer (Texture Analyzer-Model: TA-XT) under the following conditions. Plus, 'MHK Corporation') can measure the properties of soft tofu.

Probe: cylindrical shape 2 cm in diameter;

Pre-test speed at which the probe descends to sample: 1.00 mm / sec;

Test speed of penetration of the probe into the sample after it reached the sample surface: 5.00 mm / sec;

Post-test speed at which the probe has penetrated the sample (post-test speed): 5.00 mm / sec;

Target mode of the probe: distance;

A distance at which the probe recognizes the surface of the sample and penetrates the sample: 5.000 mm;

A trigger type for the probe to recognize the sample: force; And

Minimum trigger force for the probe to recognize the presence of the sample: 5.0 g

As a result of measuring the physical properties of the soft tofu, when the hardness was 120 to 160 g, it was compared with the control group (without starch or starch added but no gelatinization reaction) showing a distribution of 30 to 100 g. It was confirmed that the harder and more elastic physical properties (see Tables 2 and 3).

The tofu used in the manufacturing method of the following dried tofu of this invention is not specifically limited, A well-known tofu may be used. That is, when it is made to dry by the manufacturing method of the dried tofu of this invention using the well-known known tofu which is commercially available, the dried soft tofu which is excellent in quality compared with the conventional method of manufacturing the dry tofu can be obtained. However, in order to obtain the soft tofu which is almost the texture of the raw material after restoration at the best quality, it is more preferable to use the soft tofu prepared by the above method as a dry tofu for drying.

One aspect of the method for preparing dried tofu of the present invention may include the following process:

The prepared tofu is added to a device used for freezing and drying in the state of cooling only without preliminary freezing. The freezing process of the soft tofu is a vacuum freezing process performed under reduced pressure, and in one embodiment of the present specification, the passage time when the vacuum degree drops from 4 torr to 2.5 torr (absolute pressure) is preferably within 30 minutes, more preferably. Preferably within 15 minutes of rapid vacuum freezing.

As a result, when the product temperature of the soft tofu is lowered from 0 to -5 ° C, the transit time is preferably within 30 minutes, more preferably within 15 minutes, thereby minimizing protein denaturation in the tofu, thereby obtaining high-quality soft tofu. In other words, when the vacuum freezing method is used, the ice growth rate is remarkably faster than that of the conventional freezing method (-18 ° C. to -70 ° C.), thereby minimizing protein denaturation in the tofu. It becomes possible.

In the freeze-drying step of the soft tofu after the vacuum freezing step, in one embodiment of the present specification, preferably dried at a vacuum degree of 2.5 torr to 0.5 torr (absolute pressure), more preferably at a vacuum degree of 1.5 torr to 0.5 torr. The temperature of the hot plate in the apparatus used for the lyophilization is preferably 10 to 80 ° C, more preferably 20 to 75 ° C, and the temperature of the soft tofu is preferably 40 ° C, more preferably 35 Do not exceed ℃ ℃ to minimize denaturation of protein in the tofu.

After completing the drying process, the tofu is preferably vacuum packaged and distributed for preservation of quality.

The dried soft tofu prepared by the above drying process is closer to the texture of the raw material before drying in the physical properties of the tofu such as firmness, guminess and chewiness of the tofu after restoration as compared to the conventional general dry tofu. It is more firm and provides a soft tofu with excellent texture. Specifically, after restoring the dried tofu prepared according to the above-described manufacturing method as in one embodiment of the present specification (Comparative Test Example 3-2), the physical properties of the tofu prepared by the method of preparing the tofu of the present application were measured. As a result of measuring the properties of the soft tofu which was restored after drying under the same conditions as that of the control group, the control group showed a distribution of 50 to 90 g of solidity and a distribution of 30 to 50 g (without starch or starch added but no gelatinization reaction occurred) When compared with), it was confirmed that the harder and more elastic physical properties (see Table 3).

[Effects of the Invention]

The present invention has the advantage of providing a method of drying the tofu to provide a method for vacuum freeze-drying the tofu without preliminary freezing process to restore the taste and texture of the state before drying.

The present invention provides a method for producing a soft tofu comprising the steps of adding starch to soy milk and heating the starch to produce a soft tofu, so that the tofu having higher quality in physical properties such as hardness of the tofu and There is an advantage to providing a method of preparation thereof.

The present invention has an advantage of providing a stirring method for uniformly dispersing starch in soy milk by using starch in the form of a starch dispersion during the step of stirring the soymilk and starch during the manufacturing process of tofu.

The present invention has the advantage of providing a method for producing a dry tofu suitable for making starch by adding starch in the preparation of tofu, and drying it to dry, and a method for producing a dry tofu by vacuum freeze-drying such dry tofu .

Specifically, the present invention is superior to use as a soft tofu for the production of dry tofu as a soft tofu having higher quality in physical properties such as tofu firmness, as well as excellent texture as it is, even if it is not made with dry tofu In order to provide a soft tofu, during the tofu manufacturing process, a step of adding starch to the soymilk and gelatinizing it.

By adding starch and heating soymilk at the temperature condition to induce its gelatinization reaction, it improves the softness of the soft tofu and provides a more firm texture. To prepare dried tofu using this, the firm texture lost after drying It provides dry soft tofu with excellent physical properties after restoration, which helps to save sponge texture after drying.

Starch added in the above process is preferably modified starch, more preferably tapioca modified starch to maximize the effect of the starch. In addition, the starch is preferably added in an amount of 0.1 to 3% by weight, more preferably 1% by weight based on the total weight of the soymilk mixture, so that the cracking and bursting of the tofu by the vacuum freeze drying process during the manufacturing of the dried tofu is performed. Can be prevented.

When the starch is mixed in soymilk, in order to make the starch evenly dispersed in soymilk, the starch and dilution water are firstly stirred in a starch dispersion form by using a known homomixer, and then put into a stirring tank containing soymilk. Preference is given to proceeding with the second stirring step. In the first stirring step, preferably, an antioxidant, for example, vitamin E, vitamin C, tocopherol, green tea extract, rosemary extract, and the like may be further added and stirred, and when the antioxidant is further added and stirred, It prevents fat rancidity in the head and provides the effect of extending the shelf life of the head relatively long. When starch is directly added to soymilk, the starch is unevenly dispersed in soymilk and the grain size of the starch increases, which adversely affects the extension of the stirring time and the tofu properties, resulting in a difference in the quality of the tofu. When using the first stirred starch dispersion as described above, the stirring time of the soymilk and starch dispersion is shortened, there is an advantage that can be obtained tofu of uniform properties.

In the coagulant added to the second stirred soymilk mixture, gluconodeltalactone (GDL) is preferably not used because it decomposes the functional groups of starch and interferes with the action of starch, and more preferably calcium sulfate is used as a coagulant. Is suitable.

The soft tofu prepared by the above method provides a harder, more firm texture of the tofu in the physical properties of the tofu, such as hardness, gumminess, chewiness, and the like of the conventional tofu.

In the manufacturing method of making a dry tofu, Preferably, the tofu produced by the said method is used as a drying tofu. The present invention has the advantage of providing a method for producing dried tofu to prevent the deterioration of texture by preventing the denaturation of the protein in the tofu caused by the preliminary freezing step, in the manufacturing of dried tofu.

In addition, the freezing process of the tofu tofu is a vacuum freezing process performed under reduced pressure, in one embodiment of the present specification, the passage time when the vacuum degree drops from 4 torr to 2.5 torr (absolute pressure) is preferably within 30 minutes, more preferably. Preferably it is adjusted to within 15 minutes by rapid vacuum freezing, the passage time when the temperature of the soft tofu falls from 0 to -5 ℃ is preferably within 30 minutes, more preferably within 15 minutes within the tofu It provides a method for obtaining high quality tofu by minimizing protein denaturation. In other words, when the vacuum freezing method is used, the ice growth rate is remarkably faster than that of the conventional freezing method (-18 ° C. to -70 ° C.), thereby minimizing protein denaturation in the tofu. It becomes possible.

Further, the present invention, in the freeze-drying step of the soft tofu after the vacuum freezing step, in one embodiment of the present specification, preferably drying in the range of vacuum degree 1.5 torr to 0.5 torr (absolute pressure), and the freeze-drying The temperature of the hot plate is preferably 10 to 80 ° C, more preferably 20 to 75 ° C, so that the product temperature of the soft tofu is preferably not higher than 40 ° C, more preferably 35 ° C. There is an advantage to minimize denaturation of the protein.

The dried soft tofu prepared by the above drying process is closer to the texture of the raw material before drying in the physical properties of the tofu such as firmness, guminess and chewiness of the tofu after restoration as compared to the conventional general dry tofu. And, it is more firm and has the advantage of providing a soft tofu excellent texture.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a graph measuring the temperature change of the surface and the center of the tofu which occurs when the tofu to which tapioca modified starch is added is heated to a temperature higher than the gelatinization temperature of the tapioca modified starch.

FIG. 2 is a graph measuring the temperature change of the surface and the center of the tofu during the boiling treatment of the conventional general tofu which does not undergo starch gelatinization in the heating step of the tofu in the tofu production method.

Figure 3 is a photograph showing the difference in physical properties of the tofu in accordance with the temperature of the center of the tofu during the boiling water treatment of the tofu in the method of manufacturing starch tofu added starch.

4 is a photograph showing the difference in physical properties of the tofu in accordance with the temperature of the center of the tofu during the boiling water treatment of the tofu in the method of manufacturing a tofu with starch, together with FIG. 3.

5 is a photograph showing the difference in physical properties of the soft tofu according to the type of coagulant used in the soft tofu added with starch.

Figure 6 is a photograph showing the difference in freezing quality of the tofu frozen in the conventional way to put in a freezing vacuum and freezer.

7 and 8 are graphs showing the difference in physical properties after restoration of dried tofu prepared by adding tapioca modified starch and dried starch prepared by adding other starches, gums, sugars and enzymes, respectively.

9 is a photograph showing the difference in physical properties of dried tofu according to the type of coagulant used in the tofu to which starch is added.

10 is a photograph showing the difference between the case where the starch is added to the soymilk in the form of a starch dispersion and stirred, and the case where the starch is directly added and stirred.

11 and 12 are graphs showing the difference between the backscattering degree of soymilk stirred by adding starch and starch in the form of starch dispersion in the process of adding starch to soymilk and immediately stirring the starch.

Hereinafter, the present invention will be described by describing the following examples, test examples, and comparative test examples. However, the following Examples, Test Examples, and Comparative Test Examples are merely examples of the present invention, and the content of the present invention is not limited thereto.

Example 1

Manufacturing method (purifying method of dry tofu for drying) which undergoes gelatinization reaction of starch

(1) Step 1: Soymilk Manufacturing Process

After removing the foreign matter by washing the received soybeans, distilled water was added to the washed soybeans and soaked for 12 hours at room temperature. Distilled water was added to the soaked soybeans again, and the blend was pulverized with a blender so that the brix of soymilk was 11 brix.

The pulverized soybean was filtered through a filter to separate the soy and soy milk, and then the separated soy milk was heated and sterilized for 20 minutes while gradually increasing the temperature from 100 ° C to 105 ° C. The heat treated final soymilk was adjusted to 10.5 brix and the soymilk cooled to 10 ° C or below.

(2) step 2: adding dilution water, modified starch, antioxidant and coagulant to soymilk, followed by stirring

476 kg of the cooled soymilk was charged from the bottom of the stirring tank so as not to produce a bubble. Dissolve 5 kg of tapioca modified starch (HT2X, manufactured by Abebe) in 24 kg of distilled water, and homogenize 1 kg of antioxidant (SD-20, Tocopherol MIX, manufactured by Deferred Chemical) for 10 minutes with a homomixer. To a starch dispersion.

The starch dispersion was placed in a stirring tank containing 476 kg of 10.5 brix soymilk and stirred for 10 minutes. As a coagulant, 1.45 kg of calcium sulfate was dissolved well in 7.25 kg of distilled water, placed in the stirring tank, and stirred with the soymilk mixture.

(3) Step 3: Packaging Soymilk Mixture in Soft Tofu Pouch

508.7 kg of the soymilk mixture solution to which the coagulant was added was packed into a 1 kg soft tofu pouch with continuous stirring.

(4) Step 4: heating the packaged tofu

The packaged soft tofu was heated in a hot water bath set at 86 ° C. for 1 hour to coagulate so that the temperature of the center of the soft tofu was 83 ° C. or more.

(5) step 5: cooling the solidified tofu

The coagulated soft tofu was cooled for 5 hours in a cold water of 5 ° C. such that the central temperature of the tofu was 10 ° C. or lower, and then refrigerated.

It was confirmed that the tofu prepared by the above method exhibits the physical properties of Test Example 2 below.

Test Example 1

Temperature change of the surface and central part of soft tofu heated to a temperature higher than the gelatinization temperature of starch added to soymilk

The soft tofu with the added tapioca modified starch (HT2X, manufactured by Abebe) is considered to have sufficient gelatinization to the center of the tofu, considering that the modified starch has a gelatinization temperature of 70 to 75 ° C. Hot water treatment was performed for 60 minutes in the 86 degreeC hot water bath so that the temperature (product temperature) may be 80 degreeC or more. The temperature change of the surface and center part of a tofu head at this time is shown in FIG.

In the case of soft tofu heated to a temperature higher than the gelatinization temperature of the tapioca modified starch through the graph of FIG. 1, as a result of the gelatinization process of the starch, the temperature of the center increases relatively slowly during heating, and the temperature of the center rapidly increases after heating. We could confirm the descent. When the hot water bath was heated at 86 ° C for 30 minutes, the central temperature did not reach 60 ° C, and the tapioca-modified starch was not enough to be gelatinized, and when heated for 1 hour, the center temperature exceeded 80 ° C. Gelatinization reaction of starch became possible.

Comparative Test Example 1

Temperature Changes at the Surface and Core of Conventional Soft Tofu without Starch

The conventional general tofu with no added starch (clear soy tofu, manufactured by 'Clear Water') was obtained, and the temperature change of the surface and the center of the tofu during hot water treatment of the tofu was measured.

Referring to FIG. 2, which shows the measurement results, it was confirmed that the temperature of the center of the tofu head increased relatively sharply during heating, and that the temperature of the center gradually decreased after heating.

Test Example 2

Measurement of Physical Properties of Soft Tofu Prepared by Example 1

After preparing tofu according to the manufacturing method of Example 1, the physical properties of the tofu were measured using a physical property analyzer (Texture Analyzer-Model: TA-XT Plus, manufactured by MHK Corporation). Physical properties were measured under the following conditions.

Probe: cylindrical shape 2 cm in diameter;

Pre-test speed at which the probe descends to sample: 1.00 mm / sec;

Test speed of penetration of the probe into the sample after it reached the sample surface: 5.00 mm / sec;

Post-test speed at which the probe has penetrated the sample (post-test speed): 5.00 mm / sec;

Target mode of the probe: distance;

A distance at which the probe recognizes the surface of the sample and penetrates the sample: 5.000 mm;

A trigger type for the probe to recognize the sample: force; And

Minimum trigger force for the probe to recognize the presence of the sample: 5.0 g;

Condition to set to.

Under the above conditions, the physical properties of the tofu prepared by the manufacturing method of Example 1 are as shown in Table 1 below.

Table 1

Center temperature (℃)	Hardness	Adhesiveness	Cohesiveness	Gumminess	Chewiness	Yield amount (%)
83.22	128.04	0.97	0.85	76.58	73.52	7.01

In Table 1, the hardness indicates the force required for the sample to reach the desired deformation, and the tackiness indicates the force required for the probe to penetrate the sample and then separate again. Bury. Cohesiveness is a force that tries to maintain the shape of an object, and if it is larger than sticky, no sample will appear on the probe. Probability is the property of making a semisolid sample unswallowable and is calculated by the product of firmness and cohesiveness. Chewability is the property of making a sample in a solid state swallowable.

Comparative Test Example 2-1

Measurement of Properties of Soft Tofu without Starch Gelatinization

The composition of the tofu is the same as that of Example 1, but in order to find out the properties of the tofu which is not subjected to gelatinization of starch in the fourth step of Example 1, the six time points at which the temperature of the center of the tofu is different in the fourth step of Example 1 Sampling was carried out in order to measure the physical properties of each sample under the same conditions as in Test Example 2. The measured value thereof is shown in Table 2 below together with the data of Test Example 2.

TABLE 2

	Center temperature (℃)	Firmness (g)	Adhesiveness (gs)	Coherence	Sword	Chewability	Yield amount (%)
Primary	47.57	25.96	0.88	0.55	14.5	12.76	18.02
Secondary	51.28	26.51	0.905	0.56	14.97	13.54	20.58
3rd	55.82	33.69	0.91	0.56	18.95	17.25	11.10
4th	64.9	53.46	0.945	0.69	37.04	35	9.44
5th	74.3	62.85	0.96	0.77	48.39	46.45	7.49
6th	83.22	128.04	0.97	0.85	76.58	73.52	7.01
Correlation coefficient		0.93	0.97	0.99	0.99	0.98	0.87

Considering that the gelatinization temperature of tapioca starch, which is the starch added to the tofu tofu, is 70 to 75 ° C, sufficient gelatinization reaction of the starch may occur when the temperature of the center of the tofu is about 80 ° C or more. Only the sixth sample with a central temperature of 83.22 ° C can be considered as a soft tofu after starch reaction.

Looking at Table 2, it can be seen that the physical properties of the prepared tofu has a significant correlation with the starch gelatinization, in particular, the hardness, cohesiveness, gumminess and chewiness of the soft tofu showed a great correlation.

In addition, the amount of completion is to measure the amount of water coming out of the tofu during the same time after the production of tofu cut into a uniform size divided by the initial weight expressed as a percentage, the overall degree of completion is reduced depending on the degree of luxury of the core It was confirmed. It is believed that this resulted in reducing the amount of water required by starch becoming gelatinous and holding water present in the tofu.

In other words, the starch added to the soft tofu causes a gelatinization reaction, which makes it harder and more elastic than the soft tofu prepared without undergoing the gelatinization reaction. , It was confirmed that it is made of high quality soft tofu.

3 and 4 show photographs of the first and sixth samples during and after measurement of physical properties.

Comparative Test Example 2-2

Comparison of Properties of Soft Tofu according to the Type of Coagulant Used in Starch-Added Soft Tofu

After the same manufacturing method as in Example 1, but by varying the type of coagulant used to prepare a tofu and compared the properties of each. Specifically, 8: 2 pure tofu prepared using 1 kg of calcium sulfate as a coagulant, and calcium sulfate, magnesium chloride, and GDL in soymilk to which 5 kg of tapioca modified starch (HT2X, manufactured by Abbe) was added. The physical properties of soft tofu prepared using 1 kg of mixed coagulant mixed at a ratio of 4: 4 were compared. The test results thereof are shown in FIG. 5.

As a result of the test, the tofu using calcium sulfate as a coagulant was prepared as the tofu having the physical properties of Test Example 2, but the tofu using the complex coagulant did not contain starch or starch was added in step 4 of Example 1 Like soft tofu that has not been heated to temperatures above the gelatinization temperature, soft tofu has been prepared with properties similar to conventional soft tofu, which has lost starch properties.

More specifically, the soft tofu using calcium sulfate is significantly less diuretic, the firmness of the tofu is visible from the outside, the strength is stronger than the conventional tofu, and the texture is softer. The soft tofu using was a lot of yellowish water, and it had a soft texture and weak strength similar to that of a normal tofu without starch. The appearance of such physical properties in soft tofu using a complex coagulant was judged to be a result of GDL contained in the coagulant, which lowers the pH and degrades the functional groups of starch added to the soymilk, thereby inhibiting the effect of starch.

Example 2

Drying of soft tofu by vacuum freeze drying method

With the soft tofu manufactured by the manufacturing method of Example 1, the drying process of the soft tofu was performed.

(1) Step 1: Cutting of Tofu

In Example 1, the chilled tofu stored in the pouch was peeled off from the pouch, and the first, second and third cuts were cut through a cutter, and pretreated so that the width, length, and height of the tofu were about 5 cm or less.

(2) step 2: vacuum freezing process of the cut tofu

After cutting the tofu, divided into 4 kg each pan into a drying pan and spread well to avoid overlapping tofu. Then, the product was put into a lyophilized tube while maintaining the temperature of the soft tofu at 10 ° C. or lower. In order to proceed with the vacuum freezing, the vacuum pump was operated so that the time of vacuum dropping from 4 to 2 torr was less than 15 minutes, thereby rapidly freezing the shortest time for the temperature of the soft tofu to fall from 0 ° C to -5 ° C. Proceeded.

(3) Step 3: freeze drying process of the soft frozen tofu

The freeze-drying was performed in the range of vacuum degree 2 torr to 0.5 torr while adjusting the temperature of the hot plate to 10 to 75 ° C. based on -15 ° C. at which the freezing was completed. After 30 hours, drying was completed, and the mixture was depansed and packed.

Comparative Test Example 3-1

Freezing Quality Comparison of Tofu Frozen in Vacuum Freeze and Traditionally Frozen Tofu

Tofu frozen by the two-stage vacuum freezing method of Example 2 and put into the freezer was tested to compare the freezing quality of the frozen tofu in the conventional manner.

A comparison of freezing quality is shown in FIG. 6.

In the case of vacuum-frozen tofu, the protein was slightly denatured in several places with yellow staining, but the tofu frozen in the -70 ° C freezer was generally yellowish, and the tofu frozen in the -18 ° C freezer was very yellowish. In comparison, it was judged that only a small amount of protein denaturation occurred only in a very localized region, and that the degeneration was not so different from the original in texture after restoration.

When comparing the quality of each frozen tofu when the raw tofu texture score was 5 out of 5, the sensory evaluation of sensory evaluation after thawing vacuum frozen tofu was 5 points, which was almost no difference from the original. Tofu frozen in a -70 ° C freezer was evaluated to have 2.5 points and tofu frozen in a -18 ° C freezer.

These results indicate that the vacuum freezing method rapidly removes heat from the water in the tofu as the water vaporizes, resulting in a significantly faster ice growth rate than the conventional freezing method stored in a freezer. It is judged to be due to relatively little degeneration of the protein in the head.

Comparative Test Example 3-2

Measurement of physical properties before and after drying starch tofu and starch tofu

The tofu was prepared by the manufacturing method of Example 1, but the sample was sequentially sampled at six different time points at different temperatures of the center of the tofu in Step 4 of Example 1 as in Comparative Test Example 2-1. The physical properties of each sample were measured under the same conditions as described above, and the six samples were prepared as dry tofu by the method of Example 2. Measured under the same conditions. Its measured value is shown in Table 3 below.

TABLE 3

		Primary	Secondary	3rd	4th	5th	6th	Correlation coefficient	Control group (starch no addition)
	Center temperature (℃)	27.72	30.51	35.44	46.87	59.97	83.12
	Sample time (minutes)	12	14	17	24	34	60	0.98
Properties of Tofu before Drying	Firmness (g)	25.61	34.44	53.87	88.09	100.56	143.28	0.98	91.95
	Adhesiveness (gs)	0.82	0.86	0.95	0.93	0.97	1.01	0.85	0.96
	cohesion	0.61	0.61	0.79	0.79	0.85	0.83	0.76	0.83
	Sword	15.63	21.16	42.50	69.24	85.66	118.41	0.98	76.58
	Chewability	12.82	18.30	40.58	64.74	83.51	120.19	0.99	73.52
Properties of Soft Tofu after Restoration	Firmness (g)	36.99	40.19	44.16	50.46	57.30	60.06	0.96	47.70
	Adhesiveness (gs)	0.91	0.83	0.92	0.91	0.85	0.87	0.24	0.85
	Coherence	0.74	0.68	0.70	0.71	0.73	0.67	0.39	0.73
	Sword	27.41	27.36	30.77	35.85	42.05	40.06	0.88	43.63
	Chewability	24.80	22.71	28.30	32.62	35.53	34.85	0.86	29.44

As shown in Table 3, in the case of the soft tofu (in particular, in the case of the fifth sample) in which the starch was added but the heat of the center of the tofu was not heated to a temperature higher than the gelatinization temperature of the starch, both before and after drying, It was confirmed that the physical properties were similar to those of the tofu without starch.

In the case of the sixth sample heated to a temperature higher than the gelatinization temperature of the starch, it was confirmed that it showed the hardest (hardness) and the strongest texture (gum, chewability) not only before drying but also in the soft tofu which was restored after drying. It was confirmed that the tofu was prepared with.

Comparative Test Example 3-3

Comparison of Properties after Restoration of Soft Tofu Prepared with Tapioca Modified Starch and Dry Tofu Prepared by Addition of Other Starches, Gum, Sugars and Enzymes, respectively

The physical properties of the soft tofu prepared by adding the tapioca-modified starch to the preparation method of Examples 1 and 2 and the other starches, gums, sugars and enzymes, respectively, were compared. For other starch, powder was used, curdlan and cellulose gum were used as gum, trehalose, sorbitol, maltodextrin, poly dextrose as sugar, and transglutaminase (TG) as enzyme. Used.

In addition, hydroxy propyl methyl cellulose used as a food additive was used, and dried tofu was prepared by the preparation method of Example 1 and Example 2 using soymilk SD powder and hyaluronic acid. For each of the prepared dried tofu, the texture and cracking properties of the tofu after restoration were evaluated based on a perfect score of 5 points.

Comparison and evaluation of the physical properties are shown in Table 4, FIG. 7 and FIG.

Table 4

	Texture	offshoot
Tapioca Starch	4.9	4
Powder	2.5	3
Curdlan	3	4.5
Cellulose gum	4	One
Trehalose	3	One
Sorbitol	3	2
Maltodextrin	3.5	3
Poly dextrose	4	3
Transglutaminase (TG)	3.5	2
Hyaluronic acid	One	2
Soymilk SD Powder	3	1.5
Hydroxy Proryl Methyl Cellulose (HPMC)	2	3

[Texture Index]

[Splitting Indicator]

Comparing the properties of each soft tofu, the soft tofu prepared using tapioca modified starch was evaluated as the highest score of almost 5 points in the texture of tofu. In the splitting of the tofu, the tofu made using curdlan received the highest score, but the curdlan had a problem that the texture of the tofu was considerably inferior.

As a result of comparing the appearance preference and cut preference, the tofu using tapioca modified starch was evaluated as the best.

Comparative Test Example 3-4

Comparison of Properties of Dried Soft Tofu by Starch-Added Coagulants in Soft Tofu

Through the same manufacturing method as in Example 1 and Example 2, dry tofu was prepared by varying the type of coagulant used therein and the physical properties were compared. Specifically, in accordance with the production method of Example 1, tofu soy milk added with 5 kg of tapioca modified starch (HT2X, product of 'Abebe') was prepared by using 1 kg of calcium sulfate as a coagulant and 1 kg of GDL. The dried tofu prepared by using the method of Example 2 was first dried to compare the physical properties of the dried tofu, and then the physical properties of the soft tofu which was poured by restoring water were also compared. Comparative results are shown in FIG. 9.

In the comparison, the size of the soft tofu was prepared with the width, length, and height of 1 cm and 3 cm and 5 cm, and there were no difference in physical properties according to the size of the soft tofu.

As shown in Fig. 9, when GDL is used as a coagulant, the tofu is slightly soured by the sour taste originating from GDL itself, so it is not sensory, and the pH is lowered so that the functional group of starch is decomposed. Since the effect is canceled, it can be confirmed that not only gives a rich texture but also internal cracking after restoration.

Sensory comparison test

Comparison of Sensory Dried Tofu Prepared by Existing Dried Tofu Prepared by Preparation Methods of Examples 1 and 2

Commercially available dried tofu (Tonglim Foods tofu products per second) was obtained and a test was conducted to compare the sensory properties after restoration of dried tofu prepared by the production methods of Examples 1 and 2 above.

Donglim Food's pure tofu products per second are manufactured by conventional methods, i.e., by a manufacturing method that does not include the step of inducing a gelatinization reaction of starch, and dried by conventional methods, i.e. preliminary freezing (up to just before freezing). Freeze-dried dried tofu by the method of freeze-drying the soft tofu through.

The sensory test was conducted on 50 housewives aged 25 to 49 years by instant manufacturing and tasting instant cup soft tofu stew in the form of finished soft tofu. In the case of the Donglim food per second tofu tofu is composed of dried tofu, dried soup and liquid soup, it was marketed, hot water was poured into the sensory test, prepared by the production method of Examples 1 and 2 of the present specification In the case of dried tofu which had been dried, the tofu stew sauce (made by 'Dadam') was added to the dried tofu, and hot water was poured to perform a sensory test.

The sensory test results are shown in Table 5 below. Score was evaluated based on a perfect score of 5.

Table 5

Evaluation item	Donglim Foods Chodang Soft Tofu	Soft tofu of Example 1 and Example 2
Symbol of overall tofu	3.04	4.15
Symbol map of tofu appearance	2.88	4.04
Tofu size symbol	2.87	4.03
Tofu taste sign	3.21	4.04
Symbol of tofu texture	3.05	4.11
Symbol of tofu tenderness	2.80	4.29
Symbol of the flavor of the whole soup	3.14	3.71
Symbol of soup taste	2.98	3.61
Symbol of overall stew	3.15	3.92
Exterior sign of stew	2.86	4.00

As a result of the sensory test, the dried soft tofu produced by the manufacturing method of Example 1 and Example 2 of this application showed higher result in all evaluation items. In particular, in view of the high degree of sensory evaluation of the dried soft tofu prepared by the manufacturing method of Example 1 and Example 2 of the present specification in the degree of acceptability of the texture of tofu and the softness of tofu, said Example 1 of the present specification And when manufacturing the dried tofu prepared by the manufacturing method of Example 2, it was confirmed that the product having an excellent texture can be produced closer to the texture of the raw material before drying than the conventional method.

Example 3

Method of Making Starch Dispersion

In the preparation of tofu, starch and antioxidants were added to soymilk to prepare starch dispersion so that the starch was more evenly dispersed in soymilk.

5 kg of tapioca modified starch (HT2X, manufactured by Abebe) was dissolved in 24 kg of distilled water, and 1 kg of antioxidant (SD-20, manufactured by Deferred Chemicals) was homogenized with a homomixer for 10 minutes to form a starch dispersion. .

When the starch dispersion was added to the soymilk and stirred, it was confirmed that not only the shortening of the stirring time but also the starch was uniformly dispersed in the soymilk to obtain tofu having uniform physical properties.

Comparative Test Example 4

Comparison of the degree of dispersion in the case of stirring by applying starch directly to soymilk and stirring by applying starch dispersion

In the step of adding starch to soymilk and stirring, in order to compare the degree of dispersion of starch in soymilk when the starch is directly applied and the starch dispersion is stirred, the comparative test is carried out under the following experimental conditions. Was carried out.

470 g of commercial 10 brix soy milk was obtained and placed in two beakers, and then one beaker was added with 30 g of starch dispersion (5 g of tapioca modified starch + 25 g of dilution water) by the same method as in Example 3. 500 g of soymilk mixture is adjusted to 9.5 brix, 1% by weight starch, and another beaker is added with 5 g of tapioca modified starch and 25 g of dilution water directly to soymilk. Similarly, 500 g of the final soymilk mixture is 9.5 brix, 1% by weight starch. After adjusting to, using a stirring device, each was carried out by stirring at a rotational speed of 100 rpm for 10 minutes.

In each case, the comparison of starch dispersion in soymilk was measured by the Turbiscan LAB (Leonon Tech, Inc.) measuring the extent to which the light was transmitted and reflected (backscattering) when the light was shot on both beakers. By measuring the position, size and degree of insoluble particles in the liquid phase. The measurement of the reflected and transmitted light was carried out by scanning at 2 minute intervals for a total of 60 minutes.

The comparison of the photograph which added the starch dispersion liquid to soymilk and the photograph which added the starch immediately is shown in FIG. In addition, the backscattering result measured using the Turbiscan LAB device is shown in FIG. 11, and the result of expanding and comparing FIG. 11 is shown in FIG. 12.

As shown in Figure 10, in the case of soymilk added with starch dispersion, a starch sedimentation layer was formed near the lower end of the beaker (about 2 mm high from the bottom of the beaker), and in the case of soymilk added with starch immediately, the bottom of the beaker It was confirmed that the starch precipitate layer was formed at about 8 mm in height. This means that the size of starch particles in soymilk is much larger when starch is added immediately.

Backscattering results measured using a Turbiscan LAB instrument, as shown in Figure 11, for soymilk with starch dispersion (Figure 11, above), a point approximately 2 mm high at the bottom of the beaker In the case of soymilk with starch added immediately (Fig. 11, graph below), a high backscattering value was recorded at a point about 8 mm from the bottom of the beaker, indicating that a starch sedimentation layer was formed around each of them. . This means that when starch is directly added as described above, starch is not evenly dispersed in the soymilk and starch particles are entangled to form particles having a larger particle size.

Referring to FIG. 12, which is an enlarged view of FIG. 11, in the case where starch dispersion is added (FIG. 12, the graph above), the backscattering value is noticeable after about 18 minutes of scanning using a Turbiscan LAB apparatus. In other words, it was measured differently by making peaks at the bottom of the beaker, but when starch was added immediately (Fig. 12, graph below), peaks began to form after about 10 minutes of scanning. This means that when starch is added immediately, the dispersion of starch in soymilk remains uneven and starch particles remain large, so that the precipitation rate of starch particles is faster than when starch dispersion is added.

Therefore, from the above results, it was confirmed that adding and stirring the starch dispersion liquid in the soymilk was more uniformly dispersed in the soymilk with the starch particles smaller than when the starch was added directly.

Claims (6)

1. Soft tofu with a hardness of 120 to 160 g when the hardness of the tofu was measured under the following conditions:

   As a probe of the device for measuring the rigidity, a cylindrical shaped probe having a diameter of 2 cm is used;

   Set the pre-test speed at 1.00 mm / sec to the probe;

   Setting a test speed at which the probe penetrates into the sample after reaching the sample surface is set to 5.00 mm / sec;

   Set a post-test speed at 5.00 mm / sec after the probe has penetrated the sample;

   Set the distance at which the probe recognizes the surface of the sample and penetrates the sample to 5.000 mm;

   Set a trigger type to force for the probe to recognize the sample;

   Condition that the probe sets a minimum trigger force to 5.0 g for recognizing the presence of the sample.
2. According to claim 1, The soft tofu,

   a) adding starch and coagulant to soymilk; And

   b) a heating step of gelatinizing the starch by heating the soymilk mixture to a temperature above the gelatinization temperature of the starch;

   Tofu that is manufactured by a method for producing a soft tofu comprising a.
3. The soft tofu of claim 2, wherein the starch is denatured starch.
4. The tofu of claim 3, wherein the modified starch is tapioca modified starch.
5. The tofu of claim 2, wherein the coagulant is not gluconodelta-lactone.
6. The soft tofu of claim 5, wherein the coagulant is calcium sulfate.

Images