LAUSR

Abstract The lipid oxidation of soybean oil or peanut oil under accelerated oxidation was retarded after addition of non-saponification (N-Asta) or saponification astaxanthin (S-Asta) derived from Penaeus sinensis by-products, determined by lower malondialdehyde and peroxide value as compared with the oil controls. S-Asta or N-Asta degradation in soybean oil or peanut oil fit well to first order model. Further, the soybean oil or peanut oil containing S-Asta demonstrated lower lipid oxidation as compared to those with N-Asta addition. The thermal stability of S-Asta was further evaluated under 60–90 °C pasteurization. Significant decreases of scavenging hydroxyl radical and superoxide anion, and Asta isomers concentrations were found for S-Asta under 90 °C pasteurization; whereas the antioxidant activity of S-Asta was largely restored under 60–70 °C pasteurization. The degradation kinetics of all tans, 9-cis and 13-cis Asta, as well as Asta stereoisomers in S-Asta fit to zero order kinetics, and well described by the Arrhenius equation. The highest and lowest activation energy values of 164.83 ± 14.87 kJ/mol for all trans Asta and 17.63 ± 0.99 kJ/mol for 3S,3′R Asta suggested their highest and the lowest pasteurization stabilities. By comparison, 13-cis, 3S,3′S, and 3R,3′R showed similar thermal stabilities under pasteurization.