Quality changes in perilla seed powder related to storage duration and temperature

Abstract

Perilla seed powder (PSP) was stored at 25 degrees C, 35 degrees C, and 45 degrees C for 8 weeks. Changes in the metabolite profiles of the powders, including fatty acids, were monitored. Correlations between these changes and quality parameters, including lipid oxidation, color, and antioxidant activity, were analyzed to evaluate the effects of storage duration and temperature on PSP quality. Acid values increased significantly with the duration of storage, but not with temperature. Multivariate statistical analysis was performed to identify differences among the metabolite profiles. The PSP sample stored for 1 week at 45 degrees C and all samples stored at 25 degrees C and 35 degrees C were grouped separately from the control and samples stored at 45 degrees C for more than 4 weeks. Among the many metabolites associated with these differences, lysophosphatidylethanolamines, tocopherol, sitosterol, tryptophan, 12-hydroxyjasmonic acid glucoside, and maltose correlated negatively with quality parameters with the exception of L* and antioxidant activity. Luteolin, apigenin, luteolin 4 '-methyl ester, citric acid, isocitric acid, 9(S)-HPODE, and 3,5-octadien-2-one correlated positively with quality. Although the quantities of some antioxidants and lipids decreased during storage, the results suggested that the quality of PSP samples stored at 25 degrees C, 35 degrees C, and 45 degrees C for 8 weeks was acceptable. This was because lipid oxidation promoted by the storage environment was limited by antioxidants in the samples. These metabolites could be useful for monitoring changes in PSP quality.