Abstract: Release behavior of proteins in soybean meal during their extraction process using high performance liquid chromatography-mass spectrometry was investigated. The possibility for extraction of soybean protein isolate using multi-stage countercurrent solid-liquid extraction (MSCSLE) was also studied. The result indicated that 2S protein showed a higher release rate and more than 80% of total 2S proteins were released after extraction in two times. The total release rate of 7S and 11S proteins reached 69% after three times of extraction, indicating that 7S and 11S fractions had a lower release rate during extraction process. Increasing the concentration gradient between the solid and liquid or extending the extraction time enhanced the release of 7S and 11S fractions. The concentration of total proteins obtained using MSCSLE was higher than that obtained by multi-time extraction, resulting in higher 7S and 11S recovery rate. Under the same recovery rate of soybean protein isolate, 11% of water could be saved. During precipitation, 8% of total 7S and 11S protein could be recovered.

Key words: soybean protein isolate, high performance liquid chromatography-mass spectrum, protein identification, release, multi-stage countercurrent solid-liquid extraction

摘要： 采用液相色谱和生物质谱技术对豆粕中不同蛋白质在提取过程中的释放行为进行了研究，并将多级逆流固液提取技术用于大豆分离蛋白提取. 结果表明，豆粕中的2S组分由于分子量低和高水溶性在提取过程中释放速率较快，提取2次总释放量超过80%, 3次提取7S和11S组分总释放量约为69%，提高固相和液相间7S和11S的浓度梯度或延长提取时间有助于7S和11S组分释放. 采用该提取技术可提高提取液中的总蛋白浓度，在相同蛋白质收率下可节水11%，同时较高的蛋白质浓度可增加酸沉过程中蛋白质收率.

关键词: 大豆分离蛋白, 高效液相色谱-质谱联用技, 蛋白质识别, 释放, 多级逆流固液提取