Author(s): Nguyen Phuoc Minh
Abstract Pangasius hypophthalmus, also known as freshwater Tra catfish, is the main commercial farmed fish in the Mekong Delta of Vietnam. The rapid development of fishery products processing in Viet nam has had a significant impact on the socio-economic development of the country. This development also generates a large amount of fishery by-product. We come to investigate the hydrolysis of Pangasius hypophthalmus by-product to produce fish oil and its stability during preservation. The chemical compositions in Pangasius hypophthalmus by-product include 18.31% protein; 7.34% lipid; 63.09% moisture; 8.13% ash. Lipid recovery is 67.83%. Hydrolized fish oil contains 99.58% lipid; 0.35% moisture; 3.6 mg KOH/g acidity index; 216.28 mg KOH/g saponification; 212.68 mg KOH/g esterification; 195 gI2/100g iodine; 1 meq/kg peroxide index. Pangasius hypophthalmus fish oil contains essential fatty acids, especially DHA and EPA. So we also investigate the effect of temperature and vitamin ratio to fish oil stability during preservation.Our data demonstrate that low temperature preservation shall limit the lipid hydrolization and oxidation. Vitamin E plays a key role in lipid oxidation prevention. Keywords: Pangasius hypophthalmus by-product, hydrolysis, fish oil stability, preservation.