以蛋黄免疫球蛋白提取后的副产物-冻融蛋黄颗粒（FYP）为原料，经酶解和亚临界萃取后制备具有良好功能特性与品质的低脂蛋黄粉和蛋黄油，以期实现蛋黄资源的综合利用。首先采用蛋白酶对已发生变性的FYP进行酶解，研究酶解对其功能性质的改善效果，进而采用亚临界萃取低脂蛋黄粉和副产物蛋黄油，以低脂蛋黄粉的残油率为主要指标对萃取工艺进行优化，最终选择丙烷为萃取溶剂，萃取温度35 ℃，压力1.5 MPa，时间120 min，料液质量体积比1 g∶ 7 mL。进一步对低脂蛋黄粉的溶解性和乳化性等特性进行分析。结果表明，随着加酶量的增加，低脂蛋黄粉的溶解度上升，乳化性能提高，残油率明显下降。当加酶量为1 000 U/g时，低脂蛋黄粉的残油率为15.50%。而进一步增加酶添加量，反而会降低油脂萃取效率。因此，酶的最适添加量为1 000 U/g，此条件下制得的低脂蛋黄粉含脂量低且具有较好的溶解性和乳化性。
The byproduct of yolk immunoglobulin, freeze-thaw egg yolk pellet (FYP), was used as raw material to prepare low-fat egg yolk powder and egg yolk oil with desirable functional properties and quality through enzymatic hydrolysis and subcritical extraction, aiming to realize the comprehensive utilization of egg yolk resources. Initially, denatured FYP was subjected to enzymatic hydrolysis with alcalase, and the improvement of functional properties were investigated. Subsequently, subcritical extraction was employed to obtain low-fat egg yolk powder and the byproduct(egg yolk oil). The extraction process was optimized primarily based on the residual oil rate of low-fat egg yolk powder. Propane was selected as the extraction solvent, and the optimal extraction conditions were determined to be at extraction temperature of 35 ℃, pressure of 1.5 MPa, extraction time of 120 minutes, and solid-to-liquid ratio of 1 g∶7 mL. Furthermore, the solubility and emulsification of low-fat egg yolk powder were analyzed. The results demonstrated that the solubility and emulsifying capacity of low-fat egg yolk powder increased with an increase in enzyme dosage, while the residual oil rate decreased significantly. At the enzyme dosage of 1 000 U/g, the residual oil rate of the low-fat egg yolk powder reached 15.50%. However, further increasing the enzyme dosage led to a decrease in oil extraction efficiency. Therefore, the optimal enzyme dosage was determined to be 1 000 U/g, where the low-fat egg yolk powder has reduced fat content and desirable solubility and emulsifying properties.
GAO Jingle, GU Luping, CHANG Cuihua, LI Junhua, YANG Yanjun, SU Yujie. Comprehensive Utilization of by Products from Immunoglobulin Extraction in Egg Yolk[J]. Journal of Food Science and Biotechnology,2023,42(10):73-82.