Abstract: The study investigated the effects of light and temperature on the flavor quality of cured grass carp produced by different drying methods (all with a moisture content of 40%). For this purpose, the aerobic plate count, acid value (AV), peroxide value (POV), thiobarbituric acid (TBA) content, total fat content, total fatty acid compositions, volatile flavor components and sensory evaluation of the cured fish samples were measured. The results showed that total number of colonies was the largest (4.42 (lg (CFU/g))) in the cured fish dried with cold air in the dark, while it was the smallest (2.91 (lg (CFU/g))) in the cured fish produced by hot air drying in light. The indexes of lipid oxidation were larger in the cured fish dried in light than in darkness, but no significant difference in total fat content between the two groups was observed (P > 0.05). Furthermore, POV and TBA content of the cured fish dried by hot air were significantly larger than those of the cured fish dried by cold air (P < 0.05); however, AV and total fat content were opposite. Polyunsaturated fatty acids (PUFAs) accounted for about 40% of the total fatty acids in the cured fish, and both light and temperature had a significant effect on n-3 PUFAs such as docosahexaenoic acid (P < 0.05). The sensory evaluation results showed that drying with cold air and in light gave significantly higher sensory scores for the aroma of cured fish when compared with drying with hot air and in darkness, respectively (P < 0.05). A total of 82 volatile compounds were identified from all four cured fish samples, 14 of which were recognized as odor-active compounds including 2-nonenal. The sum of odor activity values was significantly higher in the cured fish dried in light than in darkness (P < 0.05), indicating that light may be favorable for the generation of aroma components. The results from this study provide a theoretical basis to improve the quality of cured fish in the future.

Key words: cured fish, drying methods, lipid oxidation, volatile flavor compounds