Oxidative stability of rice flour during storage under thermal oxidation and light irradiation

Abstract

The oxidative stabilities of brown and white rice flours from two varieties, Baromi2 and Samkwang, were assessed under conditions of thermal oxidation at 60 °C and fluorescent light irradiation at 25 °C. Baromi2, designed for rice flour production, and Samkwang, intended for grain consumption, exhibited differing oxidative stabilities. Utilizing solid-phase microextraction-GC/MS and electronic nose techniques, the volatile profiles and the presence of singlet oxygen were investigated. Baromi2 displayed significantly lower oxidative stability than Samkwang under both thermal and light stress (p < 0.05), largely attributed to its higher lipid and riboflavin content. The presence of 1-octen-3-ol, a primary volatile associated with singlet oxygen, was notably detected in Baromi2 brown rice flour, whereas an increased number of aldehyde volatiles were identified in its white rice flour variant. A PCA executed through the electronic nose technique substantiated the distinction in volatile profiles between Baromi2 and Samkwang, as influenced by thermal and light irradiation treatments.