Comparative study of thermal processing on the physicochemical properties and prebiotic effects of the oat β-glucan by in vitro human fecal microbiota fermentation.

This study aimed to compare the prebiotic effects of oat β-glucan between steaming and microwave processing by high-throughput sequencing. The results showed that microwave-processed oat β-glucan with lower average molecular weight (M) exhibited a more significant effect in promoting Lactobacillus and Bifidobacterium compared with steaming processed oat β-glucan with higher M at the genus level. The overall microbial composition structure results indicated that the relative abundance of Escherichia-Shigella, Lactobacillus, Enterococcus, and Dialister exhibited significant differences between the samples (p < 0.05). Additionally, the short-chain fatty acid in microwave-processed oat β-glucan fermentation slurries significantly increased (p < 0.05), and more butyrate was produced from microwave-processed oat β-glucan, which may be attributed to the higher levels of Blautia and Dialister as butyrate-producers. These results suggest that microwave processing contributed to the degradation of oat β-glucan and enhanced its prebiotic function.