Influence of red yeast rice extract fermentation on fucoidan profiles, inorganic elements and flavor properties of the kelp Saccharina japonica

This study evaluated the efficacy of fermentation on Saccharina japonica (SJ). Changes of fucoidan, heavy metals, iodine and flavor profiles of fermented SJ (FSJ) were determined. Results showed that fermentation decreased the yield and molecular weight of fucoidan and increased the levels of phenolic compounds. The antioxidant activity of fucoidan also increased. It is notable that the fermentation process resulted in a significant reduction of iodine, plumbum, chromium and cadmium. The flavor properties of SJ during the fermentation process were evaluated. A total of 44 volatile compounds were identified which were correlated with the odor attributes of FSJ. FSJ fermented for five days (FSJ-5) showed the highest overall score for desirable aroma properties dominated by “fruity” and “sweet” odors. The results proved that fermentation is a promising methodology to improve the bioactivity, safety and flavor properties of SJ.