Change of lipids in whelks (Neptunea arthritica cumingi Crosse and Neverita didyma) during cold storage

Abstract

The objective of this study was to evaluate the change of lipids in two whelk samples during cold storage. Results showed that the peroxide value (PV) and thiobarbituric acid reactive substance (TBARS) increased while the percentage of polyunsaturated fatty acid decreased, indicating that lipid oxidation occurred. The cold storage significantly reduced the levels of triacylglycerol (TAG), polar lipid (PoL), phosphatidylcholine (PC) and phosphatidylethanolamine (PE) but increased the levels of acid value (AV), free fatty acid (FFA) and monoacylglycerol, suggesting the hydrolysis of lipids. Moreover, the results showed that the lipoxygenase, acid lipase and phospholipase contributed to the hydrolysis and oxidation of lipids in the two whelks. Additionally, partial least squares discriminant analysis showed PC was positively correlated with PE, PoL and TAG, but negatively correlated with AV, FFA, PV and TBARS, indicating there is a close relationship between hydrolysis and oxidation of lipids.

Keywords: Cold storage; Hydrolysis; Lipase; Lipid; Oxidation; Shellfish; Whelk.