characterization characterization characterization

Characterizing the Structural and Functional Properties of Soybean Protein Extracted from Full-Fat Soybean Flakes after Low-Temperature Dry Extrusion.

机构信息

College of Food Science & Key Laboratory of Soybean Biology in Chinese Ministry of Education, Northeast Agricultural University, Harbin 150030, China.

National Research Center of Soybean Engineering and Technology, Harbin 150030, China.

出版信息

Molecules. 2018 Dec 10;23(12):3265. doi: 10.3390/molecules23123265.

The soy protein isolates (SPI) extracted from different extruded full-fat soybean flakes (FFSF), and their conformational and functional properties were characterized. Overall, the free thiol (SH) content of SPI increased when the extrusion temperature was below 80 °C and decreased at higher temperatures. Soy glycinin (11S) showed higher stability than β-conglycinin (7S) during extrusion. Results also indicated that the increase in some hydrophobic groups was due to the movement of hydrophobic groups from the interior to the surface of the SPI molecules at extrusion temperatures from 60 to 80 °C. However, the aggregation of SPI molecules occurred at extrusion temperatures of 90 and 100 °C, with decreasing levels of hydrophobic groups. The extrusion temperature negatively affected the emulsifying activity index (EAI); on the other side, it positively affected the emulsifying stability index (ESI), compared to unextruded SPI.

从不同膨化全脂大豆片（FFSF）中提取的大豆蛋白分离物（SPI），并对其构象和功能特性进行了表征。总体而言，当挤出温度低于 80°C 时，SPI 中的游离巯基（SH）含量增加，而在较高温度下则减少。在挤压过程中，大豆球蛋白（11S）比β-伴大豆球蛋白（7S）更稳定。结果还表明，在挤出温度为 60 至 80°C 时，一些疏水性基团的增加是由于疏水性基团从 SPI 分子的内部向表面移动所致。然而，在挤出温度为 90 和 100°C 时，SPI 分子发生聚集，疏水性基团的水平降低。与未膨化的 SPI 相比，挤出温度对乳化活性指数（EAI）有负面影响；另一方面，它对乳化稳定性指数（ESI）有积极影响。