Changes of Lipid Oxidation and Volatile Components in Ready-to-eat Fried Loach during Storage

This study aimed to examine the changes and correlations between fatty acids and volatile organic compounds in ready-to-eat fried loach (RTE-FL) over 10 days of storage by Schaal oven tests. The results showed that the peroxide value (POV) increased to 16.64 mg/100 g within first 4 days of storage and decreased over the next 6 days. The thiobarbituric acid reactive substances (TBARS) value increased gradually from 0.51 mg MDA/kg to 1.45 mg MDA/kg, while the sensory evaluation score showed the opposite trend. OPLS-DA combined with ROAV analysis revealed the 7 flavor substances with VIP ≥ 1 and ROAV ≥ 1 were identified as key differential flavor compounds. Furthermore, γ-linolenic acid (C18:3n6), linoleic acid (C18:2n6c), arachidonic acid (C20:1), pentadecenoic acid (C15:1), heneicosanoic acid (C21:0) and palmitic acid (C16:0) were significantly correlated with substances with rancid and pungent odors such as Hexanal-D (ROAV=29.29-62.09), Butanal-D (ROAV=15.95-35.59), 2-methyl propanal (ROAV=332.53-411.37), and 2-methylbutanal-D (ROAV=69.67-204.73). These findings provide valuable insights into flavor changes in RTE-FL during storage.