Adaptability Of Different Soybean Varieties To Bei-Tofu Processing

The abundant resources of soybean varieties in our country provide a large scale to be chosen for Bei-Tofu manufacturing, as a representative of Chinese traditional soy food. Bei-Tofu was popular for its good taste in China. The production and utilization of soybean in our country don't specialize in Bei-tofu. At the same time, native soy industry has been greatly impacted by the imported soybean, we try to provide a referred propose through the researches of the adaptability of native and imported soybean varieties to Bei-Tofu processing. The adaptability of different soybean varieties, the main planting soybean varieties from the northeast and Huanghuai China area and imported soybean varieties from the United States, to Chinese traditional Bei-tofu manufacturing has been studied. The main results as followed are got.1 . The protein, water-soluble protein , glycinin(11S), the ratio of glycinin(11S) to β-conglycinin(7S), oil contents and phytate acid in soybean, soymilk and Bei-tofu were analyzed. The contents of these components in soybean, soymilk and Bei-tofu between varieties were significant variation. These significance among the soybean varieties in these parameters had effects of the components on the yield and quality of Chinese traditional Bei-tofu from different soybean varieties. The yield and water-holding ability of Bei-tofu were significantly positively correlated with soybean varieties protein, water-soluble protein, 11S contents and phytate acid contents; there were significantly negatively correlations between soybean oil content Bei-tofu yield and its water-holding ability. While the correlation between the content of P-conglycinin(7S) and the ratio of glycinin(11S) to β-conglycinin(7S)and the yield were not significant. the correlation between the β-conglycinin(7S) contents and the water-holding ability were not found. For the chosen 13 varieties, those varieties, such as Zhongdou 8, Zheng 92116, Zheng 9007, Kefeng 6, Yudou 25 and Yudou 28, were suitable to Bei-tofu manufacturing for its higher yield.3. Soybean varieties affected the reology quality of Bei-tofu. The parameters, fracturability, hardness, springiness, gumminess, cohesiveness and chewiness, were significantly negatively correlated with the soy protein, water-soluble protein and 11S contents and the ratio of 11S to 7S and the phytate acid contents; while the positively correlationship were found between the parameters and the oil contents; but no significant correlations were found between those parameters and 7S contents.4. The sensory difference of Bei-tofu was analyzed through sensory evaluation. The results showed that the oil content had highly effects on the flavor and the total acceptability of Bei-tofu. The higher oil content was, the higher score was. For the chosen 13 varieties, those varieties, such as Dongnong44, Dongnong 46, Suinong 10, Suinong 14, and Zhonghuang 20, were suitable to Bei-tofu manufacturing for its good taste. But the Bei-tofu, from the imported soybean variety from the United States, with poorwater-holding ability had coarse mouth feel, which affected the total acceptability in some degree and the variety was suggested not to be suitable to Bei-tofu manufacturing in this study.In this paper, theoretical data were provided for soybean production and tofu manufacturing. And referenced methods for the enhancement of native soybean competence were provided for further studies on the advantages between the native and foreign soybean.