Fatty acid composition, lipid oxidation, and fishy odour development in seabass (Lates calcarifer) skin during iced storage

Changes in fatty acid profile, lipid hydrolysis and oxidation, development of fishy odour and volatile compounds in seabass (Lates calcarifer) skin during 18 days of iced storage were investigated. Peroxide value (PV) increased up to Day 6 and subsequently decreased up to 18 days (p<0.05). The continuous increases in thiobarbituric acid reactive substances (TBARS) values, free fatty acid (FFA) content and lipoxygenase (LOX) activity were noticeable with increasing storage time (p<0.05). Formation of FFA and hydroperoxide was confirmed by the changes in amplitude of peak at 3600-3200/cm and 1711/cm in Fourier transform IR spectra, respectively. With increasing storage time, the increase in fishy odour intensity was observed along with the formation of volatiles. Hexanal and nonanal constituted as the dominant volatile aldehydes in skin stored in ice for an extended time. Therefore, the delay of skin processing must be avoided to prevent the formation of undesirable fishy odour in skin and its products. Practical applications: Seabass skin is one of the potential raw materials for production of collagen, gelatin or other derived products. Iced storage of seabass skin affected fatty acid composition, lipid hydrolysis and oxidation, development of fishy odour and volatile compounds. Therefore, skin from fresh fish should be used and the delay of further processing should be avoided to prevent undesirable fishy odour in skin and products made therefrom.