JP2537287B2 - Calcium-reinforced sterile tofu manufacturing method - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for producing tofu, and more particularly to a method for producing sterile tofu reinforced with calcium.

[Background of Technology and Prior Art] Tofu is known as a traditional food important for Japanese people especially in maintaining a healthy diet as a vegetable protein source, and in recent years, it has become a point of balance with animal food intake. Has also been reviewed. Attempts are being made to further enhance the value as a health food by strengthening calcium, which tends to be deficient not only in Japanese but also in Westerners.

The calcium source added for calcium strengthening is
It is roughly classified into water-soluble calcium compounds such as calcium hydroxide and sparingly water-soluble calcium compounds such as tribasic calcium phosphate. Regardless of which calcium compound is added, in the production of sterilized tofu, a method of treating in a single sterilization step is preferable in terms of process simplification, so it is added before heat sterilization of soymilk. Therefore, it is required for the calcium compound to be added that it does not cause destabilization such as aggregation of soymilk protein during the process from the addition of the calcium compound to the completion of the coagulation of soymilk. This is because destabilization not only makes the tofu tissue defective, but also causes problems such as adhesion and blockage of aggregates in the sterilizer or transfer line.

Regarding the amount of calcium ion added to soy milk,
Generally, it is known that when the amount exceeds 28 mg% (weight; the same applies hereafter unless otherwise specified), protein aggregation occurs (JP-A-57-208966), and therefore the amount of the water-soluble calcium compound added is limited. This is also shown by the test example described later. Therefore, when a water-soluble calcium compound is used, for example, calcium hydroxide is added as a calcium hydroxide-sucrose complex, and the pH is adjusted to weakly acidic. It has been proposed (Japanese Patent Laid-Open Nos. 61-192258 and 61-227755). However, this method has a problem in that the process is complicated, for example, pH adjustment is essential and the process is performed under aseptic conditions.

On the other hand, although the poorly water-soluble calcium compound has no reactivity with proteins, it precipitates in soymilk and is difficult to disperse evenly, and there is a problem that a rough texture is often observed after making tofu. To solve this problem, xanthan gum, carboxymethyl cellulose, glycerin, or propylene glycol is added as a dispersion stabilizer for the sparingly water-soluble calcium compound (Japanese Patent Laid-Open No. 63-263062) and calcium citrate is pulverized ( JP-A-60-87753) has been proposed, but the former has problems such as the influence on the texture of tofu and the use of additives, and the latter means is not the production of sterilized tofu but the calcium compound and coagulant. Was proposed in the production of general tofu that can be added almost at the same time. However, as will be seen in Test Example 1 below, segregation (curd) similar to that in the case of a water-soluble calcium compound occurs. There is a problem.

The present inventors have conducted extensive studies to solve the above-mentioned problems in the calcium fortification of sterilized tofu, and as a result, by adopting a specific combination of a specific finely ground calcium source and a specific coagulant, the above-mentioned problems The inventors have found that the above can be solved and completed the present invention.

OBJECT AND SUMMARY OF THE INVENTION One object of the present invention is to provide a method for producing sterile tofu enriched with large amounts of calcium.

Another object of the present invention is to provide a calcium-fortified sterile tofu which has a good flavor and a smooth texture.

The present invention is to add calcium source to soy milk, heat sterilize and then cool, aseptically carry out addition mixing of a coagulant and subsequent filling and sealing in a container, and calcium-reinforced sterilized tofu to heat and solidify the container filled soy milk. In the production method, a calcium source is finely pulverized, and any one of the following Group A or Group B is used as the calcium source and a coagulant.

Group A: Calcium phosphate selected from the group consisting of calcium phosphate, beef bone powder and whey calcium, and / or calcium carbonate, calcium source selected from the group consisting of oyster shell and egg shell, and magnesium chloride Group B: Third group Calcium source selected from the group consisting of calcium phosphate, beef bone powder and whey calcium, and gluconodeltalactone [Detailed Description of the Invention] As a general method for producing sterile tofu, soymilk is homogenized if necessary, and UHT is used. Heat sterilization treatment such as, aseptically filter the aqueous solution of coagulant, add to soy milk, aseptically fill and seal the container,
A method of heating and solidifying a container is known (Japanese Patent Publication No. 56-23574 and Japanese Patent Publication No. 56-23577). In the present invention, these processes for producing sterile tofu can be used.

The calcium source added in the present invention includes tricalcium phosphate, cow bone powder containing tricalcium phosphate, whey calcium derived from milk, etc. (hereinafter, these may be collectively referred to as tricalcium phosphate).
Can also be used, and as the calcium carbonate, calcium carbonate, oyster shells containing calcium carbonate, egg shells, etc. (hereinafter, these may be collectively referred to as calcium carbonate) can also be used. These are all commercial products. When the coagulant is magnesium chloride, tricalcium phosphate and / or calcium carbonate is used, and when the coagulant is gluconodeltalactone, tricalcium phosphate is used. And these calcium sources have an average particle size of 5 μm.
Thereafter, it is desirably finely pulverized to 3 μm or less. The finely pulverized calcium source is added to and mixed with soy milk obtained by a conventional method or soy milk enriched with soybean protein isolate so as to obtain a desired calcium content. For example, to adjust the amount of calcium fortification to 100-200 mg per 100 g of soy milk, 1 kg of soy milk
The amount is 2.5 to 5 g for both tricalcium phosphate and calcium carbonate. From the viewpoint of flavor, it is desirable that the amount of calcium enhancement be 600 mg or less per 100 g of soy milk. Soy milk to which a calcium source has been added can be subjected to normal sterilization treatment (eg, UHT sterilizer at 140 to 150 ° C, 2 to 4).
After heating for 2 seconds), it is cooled to about 5 to 25 ° C. And, regardless of whether magnesium chloride or glucono delta lactone is used as a coagulant, an aqueous solution of approximately 15 to 20% is filtered and sterilized, and then mixed at a concentration of approximately 0.3% with respect to sterilized soymilk, and known aseptic filling. The container is filled with a machine and sealed. The sealed container is heated and solidified at about 90 ° C by immersion in a hot water tank and then cooled to room temperature.

Next, the following tests were conducted to examine the effects of various calcium sources on the tofu properties.

(Test Example 1) In Example 1 described later, instead of whey calcium, Table 1 was used.
Example except that the commercially available calcium compound shown in Table 1 was used, the addition amount to soybean milk was changed as shown in the same table, and a 15% glucono delta lactone aqueous solution or a 15% magnesium chloride aqueous solution was used as the coagulant solution. Calcium fortified sterilized tofu was produced under the same conditions as in No. 1, and the properties of soymilk and products after sterilization were visually observed. The results are shown in Table 1. In the column of “Product Properties” in Table 1, “Good” means that the tofu had good texture without inclusion of fine bubbles, and “−” sign indicates that curd was generated in the soy milk and thus the production of tofu was performed. It indicates that it was not carried out.

As shown in the above table, in the case of calcium chloride, which is a water-soluble calcium compound, and calcium citrate, which is a poorly water-soluble calcium compound (Sample Nos. 1 to 6), curd was generated at the stage of sterilizing soymilk. , Did not carry out tofu production.

As can be seen from Table 1, when magnesium chloride is used as a coagulant, it is possible to produce sterilized tofu having desirable properties by using finely ground tricalcium phosphate or calcium carbonate as a calcium compound. It was also found that the same effect can be obtained when both are used together. When glycono delta lactone is used as the coagulant, when calcium carbonate is used as the calcium source, carbon dioxide gas is generated, so that fine air bubbles are mixed in the structure of the tofu. It has been found that calcium carbonate cannot be used when delta lactone is used and tricalcium phosphate is preferred.

Next, the following test was conducted in order to investigate the effect of the amount of calcium enhancement on the flavor of tofu.

(Test Example 2) Tofu was produced in the same manner as in Example 2 except that tricalcium phosphate was added at a ratio of 100 to 700 mg per 100 g of soymilk in the amount of calcium enhancement.

The taste judgment was sensory tested by a panel consisting of 10 male and 10 female subjects, and the judgment of 16 or more subjects is shown in the table. In the judgment, "good" means that there was no roughness, persistence and off-flavor, and "bad" indicates that off-flavor was felt. The card tension is measured by a Nakamura-type card tension meter (disk diameter 10m
m). The results of this test are shown in Table 2.

This test shows that the amount of calcium enhancement per 100 g of soy milk
It was found that if the amount is 600 mg or less, there is no graininess, no stubbornness, no off-flavor, and a flavorful tofu can be obtained.

 Next, the present invention will be described in detail with reference to examples.

[Example 1] Commercially available whey calcium (manufactured by Daily Board, New Zealand, purchased from Nippon Protein Co., Ltd.) was applied to a pressure of 400 kg / cm by a wet type fine pulverizer (Nanomizer manufactured by Cosmo Instrumentation Co., Ltd.).
Repeated 5 times with ² and pulverized to an average particle size of 3 μm 2
500 kg of 0% slurry was prepared.

Next, to 6000 kg of soy milk, the above whey calcium slurry 27
Mix 0 kg (the amount of calcium enrichment is about 200 per 100 g of soy milk)
mg), 145 ° C. for 3 seconds with a steam direct heating device MDR201 (manufactured by Morinaga Milk Industry Co., Ltd.), and cooled to 15 ° C. Then, an aqueous solution containing 15% glucono delta lactone and 2% magnesium chloride as a coagulant solution is sterilized and filtered, and the filtrate is uniformly mixed with the cooled soybean milk in an amount of 2% based on the weight of soybean milk, A box-shaped container molded from 300 cc capacity laminated paper was filled with an aseptic filling machine (Tetra Pak AB300), sealed, and then immersed in a hot water tank at about 90 ° C for 40 minutes to coagulate and produce 20,000 calcium. Hardened sterile tofu was produced.

The flavor and properties of the obtained calcium-fortified sterilized tofu were examined by the same method as in Test Example 2, and as a result, the calcium compound did not cause the feeling of graininess or stubbornness, and did not show precipitation of calcium. .

Example 2 Commercially available tricalcium phosphate (manufactured by Taihei Chemical Industry Co., Ltd.) was used in a wet pulverizer (planetary ball mill manufactured by Nara Machinery Co., Ltd.).
100 kg of 20% slurry finely pulverized to an average particle size of 5 μm was prepared.

Next, to 2000 kg of soy milk, the above-mentioned tricalcium phosphate
75kg of slurry is mixed (calcium fortification amount is about 300mg per 100g of soymilk), steam direct heating device UP6000 for 3 seconds at 148 ° C.
It was sterilized by (APV) and cooled to 15 ° C. Then 15
% Glucono delta lactone aqueous solution was sterilized and filtered, and the filtrate was uniformly mixed with the cooled soy milk in an amount of 2% based on the weight of soy milk, and then treated in the same manner as in Example 1,
6,000 pieces of 300cc calcium-reinforced sterile tofu were produced.

The flavor and properties of the obtained calcium-fortified sterilized tofu were examined in the same manner as in Test Example 2. As a result, the calcium compound maintained a uniform property in which neither roughness nor persistence was felt and no calcium precipitation was observed. .

[Comparative Example] A calcium-fortified sterile tofu produced in the same manner as in Example 2 except that tricalcium phosphate was used without being finely pulverized (average particle size: 15 μm), and the calcium salt was rough and persistent. The tofu had a bad texture.

[Example 3] A commercially available beef bone meal (made by Croda Colloid Co. [UK], purchased from Nikko Fine Products Co., Ltd.) was pulverized to an average particle size of 1 µm with a wet pulverizer (Aquamizer made by Hosokawa Micron Co., Ltd.) to 20%. 100 kg of slurry was prepared.

Next, 4000 kg of soy milk was mixed with 75 kg of the above-mentioned beef bone powder slurry (the amount of calcium enrichment was about 150 mg per 100 g of soy milk), and 145
Sterilization was performed using a steam direct heating device MDU201 (manufactured by Morinaga Milk Industry Co., Ltd.) for 3 seconds at 10 ° C., and cooled to 10 ° C. Then, an aqueous solution containing 5% glucono delta lactone and 10% magnesium chloride was sterilized and filtered, and the filtrate was uniformly mixed with the cooled soymilk in an amount of 2% based on the weight of soymilk. 300cc calcium-reinforced sterile tofu treated as in 1
Made 2,000 pieces.

The flavor and properties of the obtained calcium-fortified sterilized tofu were examined in the same manner as in Test Example 2. As a result, the calcium compound maintained a uniform property in which neither roughness nor persistence was felt and no calcium precipitation was observed. .

[Example 4] Commercially available calcium carbonate (manufactured by Shiraishi Calcium Co., Ltd.) was repeatedly treated three times with a wet milling machine (high-pressure homogenizer manufactured by APV GAULIN) at a pressure of 550 kg / cm ² to give an average particle size of 2 μm.
50 kg of 20% slurry finely pulverized to m was prepared.

Next, add 2000 kg of soy milk to the above calcium carbonate slurry.
Mix 25 kg (the amount of calcium enrichment is about 10 per 100 g of soy milk)
0 mg), 148 ° C., sterilized with a steam direct heating device UP6000 (manufactured by APV) for 3 seconds, and cooled to 7 ° C. Then, a 15% magnesium chloride aqueous solution was sterilized and filtered, and the filtrate was uniformly mixed with the cooled soybean milk in an amount of 20% based on the weight of soybean milk, and then treated in the same manner as in Example 1 to obtain 300 cc of calcium. 6,000 reinforced sterilized tofu were produced.

The flavor and properties of the obtained calcium-fortified sterilized tofu were examined by the same method as in Test Example 2, and as a result, the calcium compound did not cause the feeling of graininess or stubbornness, and did not show precipitation of calcium. .

[Effects of the Invention] The effects achieved by the present invention are as follows.

(1) By the method of the present invention, it is possible to produce a calcium-reinforced sterilized tofu having a greatly increased amount of calcium.

(2) By the method of the present invention, it is possible to produce a calcium-reinforced sterilized tofu having a good flavor, a texture without roughness, and a uniform property without precipitation of calcium.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Nobuyoshi Takahashi 118 Minamibogigaoka, Asahi-ku, Yokohama-shi, Kanagawa

Claims (1)

(57) [Claims] 1. A calcium-reinforced sterilized tofu in which a calcium source is added to soybean milk, and the mixture is heated and sterilized and then cooled, and a coagulant is added and mixed, and subsequently, a container is filled and sealed to heat and solidify the container-filled soybean milk. The method for producing a calcium-fortified sterile tofu, characterized in that the calcium source is pulverized, and any one of the following groups A and B is used as the calcium source and a coagulant. Group A: Calcium phosphate selected from the group consisting of calcium phosphate, beef bone powder and whey calcium, and / or calcium carbonate, calcium source selected from the group consisting of oyster shell and egg shell, and magnesium chloride Group B: Third group Calcium source selected from the group consisting of calcium phosphate, beef bone powder and whey calcium, and gluconodeltalactone