加工鸭蛋蛋黄脂类变化的GC分析

本研究用甲醇和氯仿,使蛋黄液从一相系统转变成二相系统来提取鸭蛋中的脂类,并将脂肪甲基化,用100m×0.25mm的GC毛细管柱来测定脂类中脂肪酸的组成。气相测定结果表明,蛋黄脂肪中C16:0、C18:0、C18:1-11c、C18:2-9c,12c以及C20:3n-3的含量较高;与鲜蛋相比,生和熟的咸蛋在脂肪酸种类上没有明显的变化,但出现了C11:0和C15:0两个饱和脂肪酸。鲜蛋、生熟咸蛋在不饱和脂肪酸含量逐渐减少,分别为67.07%、66.72%、64.68%。表明加工的步骤越多,其蛋黄中的不饱和酸被破坏程度越高。鸭蛋黄通过气相分析发现含有对人体有益的多不饱和脂肪酸如DHA和EPA等。

GC Determination of Fatty Acid in Fresh Eggs and Salted Eggs

The lipids of were extracted by using methanol and chloroform to make egg yolk solution from one phase to two phases. Lipids were methylated and determined by GC equipped with 100m×0.25mm capillary column. The results of GC indicated that the concentration of fatty acids C16:0, C18:0, C18:1-11c, C18:2-9c,12c and C20:3 n-3 were highest. Compared with fresh eggs, no distinct change on the kinds of fatty acids, but there were two saturated fatty acids C11:0 and C15:0. The contents of unsaturated fatty acids were gradually less, were 67.07%, 66.72%, 64.68% respectively. The more steps in processing, the unsaturated fatty acids in yolk destroyed were higher. GC analysis indicated that there are healthy unsaturated fatty acids in yolk such as DHA and EPA.