Work

Effects of ethanol defatting on nutritional components, lipid oxidation, flavor characteristics and antioxidant capacity of snakehead peptides

Year: 2026

Type: article

Abstract: This study systematically quantified the effects of defatting degree on the quality of snakehead peptides, focusing on the interrelationships among lipid oxidation, off-flavor formation, and antioxidant capacity. Compared with non-defatted peptides (NFD), twice-defatted peptides (FD2) significantly reduced crude fat content by 74.6% (from 8.86 to 2.25 g/100g, p < 0.05), and decreased lipid oxidation indicators including TBARS by 60.2% (from 5.90 to 2.35 mg MDA/kg, p < 0.05), POV by 48.6% (from 0.241 to 0.124 meq/kg, p < 0.05), and free fatty acid content by 66.9% (from 66.39 to 21.96 μmol/g, p < 0.05). Among the 70 volatile compounds identified by GC-MS, 8 key compounds were significantly associated with off-flavor substances, namely octanal, nonanal, 1-octen-3-ol, decanal, (E)-2-nonenal, 1-octanol, (2E,4Z)-deca-2,4-dienal, and (2E,4E)-deca-2,4-dienal. They all showed varying degrees of decline after defatting, with the most potent off-flavor contributor (2E,4E)-deca-2,4-dienal decreasing by 90.7% (from 6.46 to 0.60 μg/kg, p < 0.05). Furthermore, FD2 treatment increased the proportion of peptides with molecular weights of 0.5-3.0 kDa, enhanced ABTS cation radical scavenging activity by 4.2% (from 83.4% to 87.6%, p < 0.05) and DPPH radical scavenging activity by 2.7% (from 50.9% to 53.6%, p < 0.05), while slightly decreased the ferrous ion chelating ability. This study demonstrates that two-cycle ethanol defatting is a promising and scalable processing technology for mitigating off-flavors and improving the overall quality of snakehead peptides for food industry.

Source: LWT

DOI: 10.1016/j.lwt.2026.119755