Impact of enzymatic method using crude protease from Pacific white shrimp hepatopancreas on the extraction efficiency and compositions of lipids

Lipids from striped catfish muscle were extracted with the aid of crude protease extract (CPE) from hepatopancrease of Pacific white shrimp at different levels (5-15 unit/g protein) for various hydrolysis times (0-180 min) at 60 °C. Yield of lipids increased within the first 30 min and was in agreement with increasing degree of hydrolysis. The increases in phospholipid and free fatty acid content were observed with hydrolysis times up to 30 min (p < 0.05). Yield of lipid increased when 50 mM CaCl2 was combined with CPE. CPE exhibited similar extraction efficiency to Alcalase. However, the lower yield was obtained in comparison with the solvent extraction. Higher oxidation and hydrolysis were found in lipids extracted with the aid of CPE and Alcalase, compared with those found in lipid extracted using solvents (p < 0.05). All lipid samples had triglyceride as the major component and were rich in palmitic acid and oleic acid.