Brown rice noodles (RN) are typical whole-grain products with health benefits. This study investigated the effects of rice bran fermented with Lactobacillus plantarum on palatability, volatile profiles, and antioxidant activity of brown RN. Three kinds of RN, including RN, brown RN (BRN), and bran fermented RN (BFRN), were involved in this study. The results indicated that bran fermentation reduced the cooking loss of BFRN and improved the elongation and the sensory attributes of brown RN. After fermentation, aldehydes were significantly decreased while alcohols increased, and more pleasant flavours were shown in BFRN. Fermentation increased the content of free phenolics and decreased the content of bound phenolics. Among the four major phenolics detected in this study, ferulic acid was the most abundant one in all three RN samples. The DPPH radical scavenging activity and the ferric reducing antioxidant power of free phenolics in BFRN increased significantly compared to BRN. This study proved that rice bran fermentation is an effective approach to improve palatability, enrich the flavour as well as enhance the antioxidant activity of brown RN, which may facilitate the development of processing technology for brown RN.

Summary Brown rice‐based foods are thought to be effective in preventing obesity. In this study, the effect of whole‐grain flat rice noodles (WFRN) on lipid metabolism as well as their relationship with gut microbiota was investigated in mice fed a high‐fat diet (HFD). The results indicated that WFRN reduced the degree of obesity, the lipid levels in the liver and serum, and the risk of liver inflammation. Moreover, WFRN significantly increased the contents of total short‐chain fatty acids (SCFAs) (from 162.06 ± 29.79 to 272.97 ± 59.26 μg mL−1; P < 0.05) and reshaped the composition of gut microbiota in mice cecum. As the beneficial bacteria with boosted abundance, higher Coriobacteriaceae_UCG‐002 was negatively related to the lipid levels in the liver and serum, and positively correlated with the content of hexanoic acid. On the contrary, the lower abundance of harmful bacteria Staphylococcus was positively correlated to body fat and inversely related to isovaleric acid, and Helicobacter was positively associated with higher serum LDL‐C and lower hexanoic acid. This study suggested that WFRN played a positive role in ameliorating lipid accumulation and inflammation caused by obesity, and this effect was closely associated with the regulation of gut microbiota and SCFAs.