热处理对蛋黄卵磷脂提取的影响

Influence of Thermal Processing on Egg Yolk Lecithin Extraction

为了研究热处理对卵磷脂提取率及卵磷脂成分组成的影响,采用乙醇提取法与乙醇-丙酮-正己烷法比较分析鲜蛋黄、煮蛋黄和蛋黄粉中卵磷脂提取效果。结果表明,采用乙醇提取法,鲜蛋黄、煮蛋黄和蛋黄粉中卵磷脂提取率分别为12.43%、13.19%和30.50%;采用乙醇-丙酮-正己烷法,卵磷脂提取率分别为11.89%、11.84%和0%。蛋黄粉中卵磷脂提取率与煮蛋黄和鲜蛋黄中卵磷脂提取率差异显著(P<0.05)。用双波长薄层扫描法分析乙醇法鲜蛋黄、煮蛋黄和蛋黄粉中卵磷脂的磷脂酰胆碱含量分别为87.38%、85.43%和61.86%;采用乙醇-丙酮-正己烷法所得鲜蛋黄、煮蛋黄卵磷脂中磷脂酰胆碱的含量分别为85.26%和86.13%。蛋黄粉卵磷脂纯度与鲜蛋黄、煮蛋黄相比均显著降低(P<0.05)。本研究结果表明:热处理对蛋黄卵磷脂的提取率及纯度均有影响。

The fresh egg yolk, cooked egg yolk and egg yolk powder were used as starting materials and lecithin extraction was performed using ethanol or ethanol-acetone-hexane. The thermal effect on the lecithin yields and purity was investigated. The results showed that the lecithin extracts obtained by ethanol extraction had the yields of 12.43%, 13.19%, 30.50% for the fresh egg yolk, cooked egg yolk and egg yolk powder, respectively. The lecithin extracts ob- tained by ethanol-acetone-hexane extraction had the yields of 11.89%, 11.84%, 0% for the fresh egg yolk, cooked egg yolk and egg yolk powder, respectively. The yields of lecithin from egg yolk powder is significantly different from that from fresh egg yolk and cooked egg yolk （P〈0.05）. The lecithin extracts were analyzed by TLC with dual wavelength of chromatographic canner for the percentage content of the phosphatidylcholine. The results showed that phosphatidylcholine was accounted 87.38%, 85.43%, 61.86% of the lecithin extracts by ethanol extraction for the fresh egg yolk, cooked egg yolk and egg yolk powder, respectively. The phosphatidylcholine was accounted 85.26%, 86.13% of the lecithin ex- tracts by ethanol-acetone-hexane extraction for the fresh egg yolk, cooked egg yolk, respectively. The purity of lecithin from egg yolk powder is significantly lower than that from fresh egg yolk and cooked egg yolk （P〈0.05）. It is thus con- eluded that thermal processing has an influence both on the yields of egg yolk lecithin and the purity of egg yolk lecithin.