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Background and objectives Milling, polishing, and color selection are the basic unit operation steps during rice processing, which may remove much amounts of nutritional components, such as phenolics and dietary fiber. And for a long time, rice is often overprocessed which results in a serious loss of nutrients. However, the reduction of the nutritional components during rice milling process has not been evaluated. The aim of this study was to investigate the effect of different milling processes during industrial rice processing on the free and bound phenolic content, composition, dietary fiber, and antioxidant activity (DPPH, ABTS, T‐AOC) of two kinds of rice (Dao Huaxiang and Jiangxi Indica). Findings As the milling degree increased, the loss percentages of total phenolics, flavonoids, and anthocyanins of Dao Huaxiang rice were 52.8%–76.4%, 43.3%–72.9%, and 100.0%, respectively; it was similar for the reduction percentages of total phenolics, flavonoids, and anthocyanins for Jiangxi Indica rice, which were 56.5%–77.4%, 58.7%–87.7%, and 87.5%–100%, respectively; the amounts of total dietary fiber were also decreased from 5.87 to 2.03 g/100 g DW for the Dao Huaxiang rice and from 5.14 to 2.84 g/100 g DW for Jiangxi Indica rice, respectively. Correspondingly, the content of individual phenolic, flavonoid, and anthocyanin compositions in both rice varieties decreased with the increase in milling degree during the rice processing. Antioxidant activities of T‐AOC, DPPH, and ABTS showed a same trend with phenolic profiles for the two rice varieties. Conclusions The phenolic profiles, dietary fiber, and antioxidant activities for Dao Huaxiang and Jiangxi Indica rice decreased significantly with milling degree increase during rice processing. Therefore, it is recommended that the milling and polishing degree should be reduced during rice grain processing, in order to achieve the purpose of not only satisfying the edible quality of rice but also retaining the nutritional characteristics as much as possible. Significance and novelty The rice samples in this study were from the actual industrial production industry, and the Dao Huaxiang rice and Jiangxi Indica rice were from northeast China and south China, respectively, which were representative and could provide specific and practical data for reducing milling degree in rice industry and reducing the removal of bran layer. These findings indicate that the milling degree should be reduced or controlled for retention of nutrients and acceptable sensory quality in rice.

Background and objectives Wholegrain foods have gained great attention due to their benefits on health. However, the texture, taste, and cooking quality of wholegrain foods are not good because of the bran in wholegrain. The objectives of this study were to improve the quality of brown rice noodles with rice bran that was treated by extrusion cooking. In this study, brown rice noodles with extruded rice bran (BRN‐ERB) were prepared to improve their quality compared to white rice noodles (WRN) and brown rice noodles with un‐extruded rice bran (BRN). Findings The total phenolic, flavonoid, anthocyanin, and dietary fiber contents in BRN‐ERB were 44.87 mg GAE, 36.15 mg RE, 0.11 mg Cy‐3‐O‐G, and 4.48 g per 100 g, respectively, significantly higher than those in BRN and WRN. The BRN‐ERB had the highest antioxidant activities of DPPH, ABTS, and T‐AOC, the highest resistant starch content, and the lowest starch hydrolysis rate among the three types of rice noodles. Seven phenolics, six flavonoids, and three anthocyanins were individually detected in these rice noodles, and BRN‐ERB exhibited higher contents of protocatechuic acid, p‐coumaric acid, ferulic acid, and daidzein than BRN and WRN did. The cooking and textural qualities of BRN‐ERB were improved with lower optimum cooking time and cooking loss, and higher hardness, tensile strength, and elasticity compared to BRN. Conclusions The brown rice noodles with extruded rice bran had higher contents of nutritional components than brown rice noodles with un‐extruded rice bran and white rice noodles, and better cooking and textural properties than brown rice noodles with un‐extruded rice bran. Significance and novelty The results provided the evidences that brown rice noodles prepared with extruded rice bran might become functional foods from the sources of staple rice products.

In this study, cooked brown rice (BR), germinated brown rice (GBR), fermented brown rice (FBR) and white rice (WR) were prepared by traditional cooking techniques, and extruded brown rice (EBR) was obtained by extrusion processing technology. The nutritional, cooking and sensory properties of different BR products were investigated. The results indicated that the soluble dietary fiber (SDF) content, free total phenolic content (TPC), total flavonoid content (TFC) and antioxidant capacity (DPPH, ABTS, T-AOC) in processed BR products were significantly higher than those in cooked BR and WR. The values of SDF, free TPC, TFC and T-AOC in EBR increased by 38.78%, 232.36%, 102.01% and 153.92%, respectively, compared with cooked BR. Cooked FBR and EBR had more nutrients, required less cooking time, had a softer texture and were whiter than cooked GBR and BR, especially EBR. In addition, the water absorption rate of EBR was 14.29% and 25.41% higher than that of cooked FBR and GBR. The hardness of EBR was significantly lower than that of cooked FBR and BR, even lower than that of cooked WR. However, there was no significant difference between the hardness of cooked GBR and that of cooked BR. The flavor compounds in EBR were similar to that of cooked WR, while those in cooked GBR and FBR did not differ greatly compared to cooked BR. Collectively, cooked FBR and EBR had better nutritional value, cooking and sensory properties than cooked BR, and the comprehensive value of EBR was higher.