Abstract:

The ultrasonic-assisted enzymatic hydrolysis crayfish yolk for the extraction of lipids was optimized. Meanwhile,
gas chromatography (GC) was used to analyze the fatty acid composition of crayfish yolk lipids. The results showed that
Protemax was selected as the optimal enzyme for the hydrolysis of crayfish yolk and the optimum hydrolysis parameters
were as follows: a water to substrate ratio of 3:1 (mL/g), an enzyme concentration of 0.6%, a hydrolysis temperature of
52 ℃, and ultrasonication at a power of 150 W for 125 min. Under these conditions, the extraction yield of lipids was up to
77.86%. Meanwhile, 26 fatty acids (C14–C24) were found in the extracted lipids as indicated by GC analysis, with saturated
fatty acids (SFAs), monounsaturated fatty acids (MUFAs) and polyunsaturated fatty acids (PUFAs) accounting for 40.67%,
31.47% and 27.92% of the total fatty acids. Moreover, the detected ω-3 and ω-6 fatty acids together accounted for 9.68% of
the total fatty acids.

Key words: crayfish, crayfish yolk, lipids, enzymatic hydrolysis, ultrasonic, fatty acid