Abstract:
This research aimed to 1) study the basic recipe suitable for making firm tofu 2) study the appropriate time for soybean germination, and 3) study chemical and physical properties of high GABA (gamma-aminobutyric acid) firm tofu from germinated soybean milk, and 4) study the consumer acceptance of high GABA firm tofu from germinated soybean milk. The result of the research found that the 3rd recipe of soybean milk is an appropriate basic recipe for making firm tofu. It consists of raw soybean seeds, 5% distilled vinegar, and clean water. The result of the study of the optimum time for soybean germination by evaluating sensory quality in terms of appearance, color, smell, taste, texture, and overall preference by using 9 point hedonic scale found that tasters accept the firm tofu formula using germinated soybeans at 24 hours with a high level of approval. In terms of appearance, color, smell, and taste, the average scores are 7.98, 7.74, 7.92, and 8.06, respectively. In terms of texture and overall preference, testers favor the recipe using soybeans germinated at 12 hours, with average scores of 7.64 and 7.74, respectively. The firm tofu product from soybean that is germinated for 24 hours contains 27.44 mg of GABA, which is higher than the firm tofu product from un-germinated soybeans that has only 15.33 mg of GABA. Both recipes of firm tofu have not different brightness value (L*). The firmness value of the basic recipe tofu is 31.14 newtons, which is higher than the firm tofu recipe using germinated soybean at 11.23 newtons. The flexible value (Springiness) of both recipes is similar at 5.58 newtons and 5.36 newtons. Consumer groups accept high GABA firm tofu product from germinated soybean milk, accounting for 100 percent. They interest in the product 96 percent, purchase the product 89.33 percent. Also, they know the benefit of firm tofu product 76.67 percent.