KR20190051309A - The manufacture method of soybean curd prepared by using concentrated grapefruit as coagulating agent - Google Patents

Abstract

The present invention relates to a method of making tofu, comprising a step of adding a coagulant containing grapefruit concentrate mixed with magnesium chloride to make tofu; and tofu made by the method, which has improved yield, sugar content, water holding capacity, water content, and hardness. The tofu made by the method of the present invention, since it uses a natural substance, the grapefruit concentrate as a coagulant along with a chemical coagulant, magnesium chloride, may serve to reduce the chemical coagulant content of tofu compared to a conventional tofu. According to the present invention, there may be produced a tofu which has increased yield, has improved mouth-feel due to increased water content and water holding capacity, and has desirable sensory properties due to increased sugar content.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing soybean curd containing a grapefruit concentrate,

The present invention relates to a method for producing tofu, which comprises the step of adding to the tofu a grapefruit concentrate and magnesium chloride as a coagulant to produce a tofu, a yield, a sugar content, a water holding capacity and a moisture content for the tofu produced by the method.

Tofu is a type of non-fermented soybean food which is widely consumed in Korea and Japan and China. Tofu is produced by soaking the washed soybeans at room temperature in water, soaking the so-called beans with water, The soybean juice prepared in the step of grinding is heated, mixed with a chemical coagulant, mixed and cooled to 75 to 78 캜, and fully coagulated. Thus, a coagulant such as calcium chloride, calcium sulfate or glucono-δ-lactone, which is used in the conventional production of tofu, can not be completely removed in the production process, There is a problem that harmful substances contained in these chemical coagulants bind to the proteins of the head. In recent years, metal ions such as calcium, magnesium and acid such as calcium sulfate, magnesium chloride and gluconoterolactone are often used. However, since the general coagulant such as calcium sulfate has a large amount of water continuously generated in the state of the finished product, Decrease in yield and head can easily be altered. Therefore, it is difficult to store in a refrigerated state for a long time, and softness and elasticity inherent to the tofu are easily deteriorated, resulting in deterioration of taste and texture. The tofu thus produced was unreliable in terms of the stability of the food, poor in taste and texture, and insufficient in nutritional content, making it difficult to expect a high quality tofu.

Accordingly, the present invention aims to develop a substance which can be substituted with a natural coagulant while reducing the content of the chemical coagulant.

Korean Patent Publication No. 10-2008-0098774

It is an object of the present invention to provide a process for producing soybean milk, comprising the steps of: (1)

(2) a step of expanding the above-ground beans and then separating the soybean milk by filtration; And

And a step (3) of heating the soybean milk and then adding a grapefruit concentrate and magnesium chloride as a coagulant to prepare a tofu.

Another object of the present invention is to provide a tofu for yield, yield, water holding capacity, moisture content and hardness to be produced by the above production method.

In one aspect of the present invention,

The present invention relates to a process for producing soybeans, comprising: (1)

(2) a step of expanding the above-ground beans and then separating the soybean milk by filtration; And

(3) heating and cooling the soymilk, and then adding a grapefruit concentrate and magnesium chloride as a coagulant to prepare a tofu.

As a result of intensive efforts to develop a natural coagulant that can reduce the content of magnesium chloride as a chemical coagulant, the present inventors have found that grapefruit concentrate can be used as a natural coagulant. As a result of using grapefruit concentrate as a coagulant, The present invention has been accomplished based on the findings that it is possible to produce a tofu having excellent sensory properties by increasing the yield, increasing the moisture content and the water holding capacity, and having good texture and increased sugar content.

In the present invention, the method for producing the tofu includes a step (1) of milling the dried soybeans after they are soaked in water.

The soybean of the present invention is not particularly limited as long as it is generally used in the production of tofu. In general, soybeans of the present invention can be soybeans. In the present invention, it is called 3-13 hours for soaking in beans, and is used for making tofu, specifically in 3-4 hours in summer, 5-6 hours in spring and autumn, and 12-13 hours in winter, . If the beans are shredded for less than 3 hours, the beans will not be fully squeezed and the process of grinding will not be smooth and the tofu will not be smooth enough. If the beans are shredded for more than 13 hours, the beans will be degenerated. It is preferable to immerse soybeans in warm water because the rate of absorption at the time of soaking is higher as the temperature of the water is higher. However, water temperature of 15 to 25 ° C is suitable because enzyme decomposition and propagation of microorganisms are a concern. In the present invention, water was immersed in water at 20 to 25 DEG C for 10 to 11 hours.

In the present invention, the pulverization of soybeans can be carried out by appropriately grinding the pulverized soybeans by adding water to the soybeans at a predetermined ratio using a mill, a mechanical pulverizer or an electric pulverizer.

In one embodiment of the present invention 1000 g dried beans were washed three times, mixed with five times the weight of dried soybeans, blended for 10-11 hours, and ground twice with a 1 horsepower vertical soybean milk.

In addition, in the present invention, the method for producing the tofu includes a step (2) of growing soybean curd and then separating the soybean milk by filtration.

The addition of the present invention can be carried out by heating the ground beans to 90 to 100 캜 for 40 to 60 minutes while stirring, and then heating them for 5 to 15 minutes after reaching the temperature. More specifically, after reaching 94 [deg.] C, it can be carried out by further heating for 10 minutes.

The denaturation of some proteins is induced by the increase of sugar, and the beans (bean juice) ground are separated into bean curd and soybean curd. When the temperature of the heated bean curd (soybean curd) is 90 to 100 ° C., the extraction rate of soybean solid, crude protein and crude fat is high when the soybean curd is separated from the ground bean (soybean curd) and the extraction yield of soybean milk is high. Further, when the temperature of the ground soybean (bean juice) obtained by heating is higher than or lower than 90 to 100 ° C, or when the additional heating time is less than or more than 5 to 15 minutes, the soy milk extraction yield is decreased.

The heated bean juice is filtered to separate the soybean milk and the bean curd. The filtration can be performed by a conventional method, and is not particularly limited.

In one embodiment of the present invention, the soybean curd (soybean curd) was heated while stirring the soybeans until the temperature of the soybean curd was 94 ° C. After reaching 94 ° C, the soybean curd was further heated by heating for 10 minutes. Then, the bean curd was filtered with a filter cloth to obtain soy milk.

In addition, the method for manufacturing the tofu of the present invention includes a step (3) of heating the soymilk, and then adding the grapefruit concentrate and the magnesium chloride as a coagulant to prepare a tofu.

The filtered soymilk is heated to 85-90 캜 and then cooled. When the temperature of the cooled soybean milk reaches 75-80 DEG C, a coagulant obtained by mixing grapefruit concentrate and magnesium chloride is added and solidified.

In the present invention, 1.0 wt% to 6 wt% of a coagulant may be added to the heated and cooled soymilk, and the coagulant may be added in an amount of 1.25 wt% to 5 wt% and 0 to 0.1 wt% . More specifically, the coagulant may be added to 1.25% by weight of grapefruit concentrate and 0.1% by weight of magnesium chloride.

In one embodiment of the present invention, the filtered soymilk is heated and cooled, and then 1.0 wt% to 6 wt% of the coagulant is added. Specifically, the coagulant is 1.25 wt% to 5 wt% 0.1% by weight of the soybean milk was solidified, and the soybean milk was solidified by pressing it into a tofu mold to produce tofu to prepare the tofu of Examples 1 to 4. The tofu mold used for the compression and molding was 7.5 cm × 9.7 cm × 5.5 cm. The lid of the tofu mold was 7 cm × 9.3 cm × 4.45 cm, and the brick used for the compression was 11 cm × 22.5 cm × 6.4 cm / 3.3 kg, the compression time was 4 hours, and the compression force was 451.92 Pa. After the compression and molding, it was cooled for 24 hours.

In one embodiment of the present invention, when the grapefruit concentrate and magnesium chloride were used together as a coagulant, the magnesium chloride content could be reduced, the yield could be increased, the water content and the water holding capacity could be increased And it was possible to provide tofu having good texture and high sugar content and excellent sensibility. More specifically, the yield of the tofu of Example 1, in which the grapefruit concentrate was 1.25 wt% and the magnesium chloride was 0.1 wt%, was the highest, and the sugar content was higher than that of the commercial stew tofu and the commercial tofu used as the positive control. And the water content was similar to that of commercial tofu. Also, the tofu of Examples 1 and 3, in which the grapefruit concentrate was used at 1.25% and 2.5%, was similar in hardness to commercially available stigma tofu and could be used as a tofu for a stew, and in Examples 2 and 4 using 1.5% and 5% The tofu was similar in hardness to the commercial tofu tofu.

The present invention relates to a method for producing tofu, comprising the step of adding a coagulant obtained by mixing grapefruit concentrate and magnesium chloride to produce a tofu, and a tofu for yield, sugar content, water holding capacity and moisture content produced by the above- .

The tofu produced by the method of the present invention can be used as a coagulant in combination with magnesium chloride as a chemical coagulant and a natural grapefruit concentrate as a coagulant to lower the content of the conventional tofu chemical coagulant and increase the yield and increase the water content and water holding capacity And the sugar content is increased, so that a tofu having excellent sensory properties can be produced.

Figure 1 shows the yield of tofu.
Figure 2 shows the pH of the head.
Figure 3 shows the sugar content of the tofu.
4 shows the chromaticity of the head.
Figure 5 shows the water holding capacity of the tofu.
Figure 6 shows the moisture content of the head.
Figure 7 shows the hardness of the head.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

< Example  1>

1000 g of dried soybeans were washed three times, mixed with 5 times the weight of dried soybeans, and roasted for 10-11 hours. The soaked soybeans were harvested using 8 times the weight of dried soybeans, It was processed 2 times by a machine. The ground beans were heated to 94 DEG C for 40 to 60 minutes with stirring, and after reaching 94 DEG C, they were further heated by heating for 10 minutes. Then, the bean curd was filtered with a filter cloth to obtain soy milk. Further, the filtered soymilk was heated until reaching 85-90 캜, and then cooled to adjust the temperature of the soy milk to 75-80 캜. After that, grapefruit concentrate and magnesium chloride were added as a coagulant and solidified. At this time, 12.5 g of grapefruit concentrate was diluted with 25 g of water. To 975 g of the heated soybean milk, 0.1 g (1 g) of grapefruit concentrate and magnesium chloride diluted in 25 g of water were added, 1.25% (12.5g) of grapefruit concentrate, and 0.1% of magnesium chloride. The coagulated soymilk was pressed into a tofu mold and molded to produce tofu. The tofu mold used for the compression and molding was 7.5 cm × 9.7 cm × 5.5 cm. The lid of the tofu mold was 7 cm × 9.3 cm × 4.45 cm, and the brick used for the compression was 11 cm × 22.5 cm × 6.4 cm / 3.3 kg, the compression time was 4 hours, and the compression force was 451.92 Pa. After the compression and molding, it was cooled for 24 hours.

< Example  2>

Tofu was prepared in the same manner as in Example 1, except that 1.5% (15 g) of the above grapefruit concentrate and 0.075% (0.75 g) of magnesium chloride were added and solidified.

< Example  3>

Tofu was prepared in the same manner as in Example 1, except that 2.5% (25 g) of grapefruit concentrate and 0.005% (0.5 g) of magnesium chloride were added and solidified.

< Example  4>

Tofu was prepared in the same manner as in Example 1, except that 5% (50 g) of the grapefruit concentrate was added and solidified.

< Comparative Example  1>

Tofu was prepared in the same manner as in Example 1, except that 0.2% (2 g) of magnesium chloride was added and solidified.

The contents of the coagulants used for the production of tofu in Examples 1 to 4 and Comparative Examples are summarized in the following table.

Experimental Example  1: Yield measurement

The yields of the control tofu prepared in Examples 1 to 4 and Comparative Example 1 were measured. The results are shown in Fig. As a result, the highest yield was obtained in 98.57% of tofu using 1.25% of grapefruit concentrate and 0.1% of magnesium chloride as a coagulant, and the yield of grapefruit concentrate was significantly higher than that of using only magnesium chloride as a coagulant .

Experimental Example  2: pH measurement

The pH of the control tofu prepared in Examples 1 to 4 and Comparative Example 1 was measured. The results are shown in Fig. As a result, the control tofu of Comparative Example 1 in which the commercially available stigma tofu was used as a coagulant was pH 6.623 ± 0.017, 6.573 ± 0.001 in commercial tofu tofu, and 2% in magnesium chloride were measured to be 6.318 ± 0.225, The pH difference with tofu was the smallest.

Also, the pH of the grapefruit concentrate was 3.339 ± 0.040, and in the case of the tofu prepared in Examples 1 to 4, it was confirmed that the pH was significantly lowered as the concentration of grapefruit concentrate increased. Therefore, the tofu having a pH similar to that of the positive control was the tofu of Comparative Example 1 containing 2% of magnesium chloride, the tofu of Example 2, which was prepared using 1.5% of grapefruit concentrate and 0.075% of magnesium chloride as a coagulant.

Experimental Example  3: sugar content ( Brix% ) Measure

The sugar content of the soy milk prepared in Examples 1 to 4 and Comparative Example 1 was measured. The results are shown in Fig. As a result, the sugar content of commercial stew tofu and commercial tofu used as positive control groups were 0.77 ± 0.09 and 0.77 ± 0.04, respectively. There was no significant difference between the positive control and the control of Comparative Example 1 using 2% of magnesium chloride, Example 2 using 1.5% grapefruit concentrate and Example 3 using 2.5% grapefruit concentrate, Showed the highest sugar content. In Example 1 using 1.25% of grapefruit concentrate, the sugar content was significantly higher than that of the positive control group.

Experimental Example  4: External chromaticity measurement

The external chromaticity of the head manufactured in Examples 1 to 4 and Comparative Example 1 was measured. The results are shown in Fig.

In the case of L (lightness), there was no significant difference in the control tofu of Comparative Example 1 using 88.48 ± 0.85 and 2% of magnesium stearate, respectively, which were used as positive control group, 87.72 ± 0.06. Also, the value of marketed tofu was 89.77 ± 0.61 as the positive control group.

The tofu of Example 1 using 1.25% of grapefruit concentrate and 0.1% of magnesium chloride was 86.09 ± 0.25, which was closest to the commercial tofu. The tofu of Example 2 using 1.5% of grapefruit concentrate and 0.075% of magnesium chloride was 85.75 + -0.24, 2.5% of grapefruit concentrate, 0.005% of magnesium chloride, 84.97 + 0.28 of tofu of Example 3 and 5% of grapefruit concentrate The tofu of Example 4 was 82.84 ± 0.06, and the higher the concentration of grapefruit concentrate, the lower the brightness value.

In the case of a (redness), there was no significant difference in the control tofu of 3.63 ± 0.17 in Comparative Example 1 using 3.90 ± 0.32 of commercial stew head and 2% of magnesium chloride used as a positive control. The commercial tofu was 3.63 ± 0.21.

The tofu of Example 1 using 3.34 ± 0.18 of the grapefruit concentrate, 1.5% of the grapefruit concentrate and 0.075% of the magnesium chloride was 4.69 ± 0.03, 2.5% of the grapefruit concentrate, 0.005 of magnesium chloride % Was 4.84 ± 0.10 in Example 3, and there was no significant difference between them. The tofu of Example 4 using 5% of grapefruit concentrate was 5.80 ± 0.02, and the value of redness was increased as the concentration of grapefruit concentrate was higher.

b (yellowness), the commercial stew tofu used as a positive control was 3.72 ± 0.46, showing the lowest yellowness value. The marketed tofu was 5.23 ± 0.54. The tofu of Example 2 using 4.45 ± 0.16, 1.5% of grapefruit concentrate and 0.075% of magnesium chloride was 5.65 ± 0.04, 2.5% of grapefruit concentrate, and 0.005 of magnesium chloride, respectively, using 1.25% of the grapefruit concentrate and 0.1% % Was 6.51 ± 0.13 for the tofu of the Example 3, and 8.13 ± 0.03 for the tofu using the 5% grapefruit concentrate. As the concentration of the grapefruit concentrate increased, the yellowness value increased.

Experimental Example  5: Internal chromaticity measurement

The internal chromaticities of the tofu prepared in Examples 1 to 4 and Comparative Example 1 were measured. The results are shown in Fig.

In the case of L (lightness), the brightness value of the tofu of Example 1 using the commercial stew tofu, the commercial tofu tofu, the tofu of the comparative example 1 using 2% of magnesium chloride, the grapefruit concentrate 1.25% and the magnesium chloride 0.1% There was no difference.

Also, there was no significant difference in the tofu of Example 2 using 5% of the grapefruit concentrate of Example 2 and 1.5% of the grapefruit concentrate and 0.075% of magnesium chloride. The head value of Example 3 using 2.5% of grapefruit concentrate and 0.005% of magnesium chloride was 88.33 ± 0.41. The lightness was different according to the ratio of grapefruit concentrate and magnesium chloride.

In the case of a (redness), there was no significant difference in the redness of the commercial stew tofu and commercial tofu tofu, showing the lowest redness. The tofu of Example 4 using 5% of grapefruit concentrate and the tofu of Example 2 using 1.5% of grapefruit concentrate and 0.075% of magnesium chloride were also not significantly different.

In the case of b (yellowness), 3.91 ± 0.41 of the head of Example 1 using 1.25% of the grapefruit concentrate and 0.075% of magnesium chloride, and 3.43 ± 0.014 of the head of Example 3 using 2.5% of the grapefruit concentrate and 0.005% of magnesium chloride There was no difference. Also, there was no significant difference between 5.15 ± 0.07 of the head of Example 2 using 5.1% of grapefruit concentrate and 0.075% of magnesium chloride and 5.13 ± 0.28 of the head of Example 4 using 5% of grapefruit concentrate.

Experimental Example  6: Capacity measurement

The water holding capacity of the control head prepared in Examples 1 to 4 and Comparative Example 1 was measured. The results are shown in Fig.

The positive control group showed the highest water holding capacity of 43.27 ± 4.82% and 40.62 ± 3.40% in commercial tofu tofu and commercial tofu tofu, respectively.

The tofu of Example 2 using 1.5% of grapefruit concentrate and 0.075% of magnesium chloride was 38.60 ± 0.67% and 37.58 ± 4.58%, respectively, using 1.25% of the grapefruit concentrate and 0.075% of magnesium chloride. And there was no significant difference from the positive control group.

The water-holding capacity of the tofu of Comparative Example 1 using 2% of magnesium chloride was 30.07 ± 4.09%, 2.5% of the grapefruit concentrate and 0.005% of the magnesium chloride, compared with 32.47 ± 3.00% of the tofu of Example 3 using the other grapefruit concentrate It showed somewhat low water holding capacity.

Experimental Example  7: Moisture content measurement

The moisture content of the tofu prepared in Examples 1 to 4 and Comparative Example 1 was measured.

The moisture content of the tofu of Example 1 using commercially available stew tofu, commercially available tofu tofu, 1.25% of grapefruit concentrate and 0.1% of magnesium chloride was not significantly different, and the tofu of Example 1 was different from that of other Examples and Comparative Example 1 The water content was higher than the control. The remaining tofu of Comparative Example 1 and Examples 2 to 4 showed lower moisture content than the commercial tofu, which is a positive control.

Experimental Example  8: Hardness measurement

The hardness of the tofu prepared in Examples 1 to 4 and Comparative Example 1 was measured. The hardness measurement standard is shown in Table 2.

In the case of the positive control group, the hardness of the commercial stew tofu was lower than that of the commercial tofu. The control tofu of Comparative Example 1 using 2% of magnesium chloride showed the highest hardness. The tofu of Examples 1 and 3, in which the grapefruit concentrate was used at 1.25% and 2.5%, was similar in hardness to commercial stew head tofu, and the tofu of Examples 2 and 4 using the grapefruit concentrate at 1.5% and 5% It is possible to use it as an appetite tofu because it is similar in hardness to the commercial edible tofu.

In the present invention, grapefruit concentrate as a natural coagulant and magnesium chloride as a chemical coagulant were mixed singly or in combination to prepare a tofu. Tofu, which was most similar to commercial tofu during the course of taste, texture, cutting, and the like through physicochemical experiments after the manufacture of tofu, showed that the tofu of Example 1, which was used at a concentration of 1.25% of grapefruit concentrate and 0.1% of magnesium chloride, Of the tofu. In addition, the tofu of Example 2 using 1.5% of grapefruit concentrate and 0.075% of magnesium chloride was next similar to the commercial tofu as a positive control.

Claims (7)

Step (1) of soaking the dried beans in water and then grinding;
(2) a step of expanding the above-ground beans and then separating the soybean milk by filtration; And
(3) heating and cooling the soymilk, and then adding grapefruit concentrate and magnesium chloride as a coagulant to prepare a tofu. The method for producing tofu according to claim 1, wherein the coagulant is added to the heated and cooled soymilk in an amount of 1.0 wt% to 6 wt%. The method according to claim 1, wherein the coagulant is 1.25 wt% to 5 wt% of grapefruit concentrate and 0 to 0.1 wt% of magnesium chloride. The method according to claim 1, wherein the coagulant is 1.25 wt% of grapefruit concentrate and 0.1 wt% of magnesium chloride.  The process for producing soybean curd according to claim 1, wherein the soybean is fermented by heating until the soybean curd is stirred at a temperature of 90 to 100 占 폚, and after the temperature is reached, further heating is carried out for 5 to 15 minutes. Way. The method according to claim 1, wherein the tofu is increased in yield, sugar content, water holding capacity and moisture content. A tofu for yield, sugar content, water holding capacity and moisture content produced by the method of any one of claims 1 to 6.

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