大豆球蛋白G4蛋白B3亚基导致中式高盐稀态酱油二次沉淀的形成

B3 Subunit in Soy Globulin G4 Protein Leads to the Formation of Secondary Precipitation in Chinese-type High-salt and Diluted-state Soy Sauce

摘要:

该文以日式酱油为对照，系统分析了pH、Fe3+/Fe2+、多酚、大豆多糖、大豆蛋白酶解物、NaCl、乙醇和温度对中式高盐稀态酱油二次沉淀生成量的影响，并对比分析了它们的游离氨基酸组成和敏感蛋白。结果显示除乙醇（<1.8%）外，上述其他因素均对中式高盐稀态酱油二次沉淀生成量具有显著影响（p<0.05），仅pH（6.5）、大豆蛋白酶解物、NaCl和温度（60 ℃）对日式酱油二次沉淀生成量有显著影响（p<0.05）；中式高盐稀态酱油15种游离氨基酸含量及其平均疏水值（HΦavg）显著低于日式酱油相应值；中式高盐稀态酱油中大豆球蛋白中的B3亚基（敏感蛋白）含量显著高于日式酱油（未检出）。综合上述结果推测大豆球蛋白G4蛋白B3亚基是中式高盐稀态酱油二次沉淀形成的关键物质，中式高盐稀态酱油二次沉淀可能是通过B3亚基-Fe3+/Fe2+-多酚复合物和B3亚基-大豆多糖-Na+-Cl-复合物途径形成。上述研究结果将为解决中式高盐稀态酱油二次沉淀问题提供理论参考。

Abstract:

In this paper, Japanese-type soy sauce was used as control, the effects of pH, Fe3+/Fe2+, polyphenol, soybean polysaccharide, soybean protein hydrolysate, NaCl, ethanol and temperature on the secondary precipitation, and the free amino acid composition and sensitive proteins in Chinese-type high-salt and diluted-state soy sauce were systematically analyzed. The results showed that all the above factors except ethanol (<1.8%) had significant effects on the secondary precipitate formation of Chinese-type high-salt and diluted-state soy sauce (p<0.05), only pH (6.5), soy protein hydrolysate, NaCl and temperature (60 ℃) had markedly effects on the secondary precipitate formation of Japanese-type soy sauce (p<0.05); the contents of 15 free amino acids and their average hydrophobic value (HΦavg) in Chinese-type high-salt and diluted-state soy sauce were significantly lower than those in Japanese-type soy sauce; the content of soy globulin B3 subunit (sensitive protein) in Chinese-type high-salt and diluted-state soy sauce was significantly higher than that in Japanese-type soy sauce (not detected). Based on the above results, it was speculated that B3 subunit in soy globulin G4 protein was the key substance of secondary precipitate formation in Chinese-type high-salt and diluted-state soy sauce, the secondary precipitate in Chinese-type high-salt and diluted-state soy sauce may be formed through B3 subunit-Fe3+/Fe2+-polyphenol complex and B3 subunit-soybean polysaccharide-Na+-Cl- complex. The above results will provide a theoretical reference for solving the secondary precipitation problem in Chinese-type high-salt and diluted-state soy sauce.