Rice Bran: From Waste to Nutritious Food Ingredients

Abstract

Rice (Oryza sativa L.) is a principal food for more than half of the world’s people. Rice is predominantly consumed as white rice, a refined grain that is produced during the rice milling process which removes the bran and germ and leaves the starchy endosperm. Rice bran is a by-product produced from the rice milling process, which contains many bioactive compounds, for instance, phenolic compounds, tocotrienols, tocopherols, and γ-oryzanol. These bioactive compounds are thought to protect against cancer, vascular disease, and type 2 diabetes. Extraction of rice bran oil also generates various by-products including rice bran wax, defatted rice bran, filtered cake, and rice acid oil, and some of them exert bioactive substances that could be utilized as functional food ingredients. However, rice bran is often utilized as animal feed or discarded as waste. Therefore, this review aimed to discuss the role of rice bran in metabolic ailments. The bioactive constituents and food product application of rice bran were also highlighted in this study. Collectively, a better understanding of the underlying molecular mechanism and the role of these bioactive compounds exerted in the rice bran would provide a useful approach for the food industry and prevent metabolic ailments.

Role of Microbial Fermentation in the Bio-Production of Food Aroma Compounds from Vegetable Waste

“…Rice bran is, in fact, a by-product of rice milling and is generally used as an animal feed ingredient or as raw material for the production of fertilizers [53]. However, it has potential for being valorised because it is a good source of dietary fibre, vitamins, minerals, protein, lipids, and some phytochemicals such as ferulic acid, γ-oryzanol, and tocopherol [54].…”

Modified rice bran arabinoxylan as a nutraceutical in health and disease—A scoping review with bibliometric analysis

“…In 2021, the global rice production was 787 million metric tons, with approximately 80 million tons of rice bran being generated [ 1 ]. Traditionally, rice bran was considered an agricultural waste with only limited usage as animal feed [ 2 ]. Disposing such a high volume of industrial food residuals is a substantial undertaking and, without proper management, can pose significant environmental and public health issues [ 3 ].…”

“…Disposing such a high volume of industrial food residuals is a substantial undertaking and, without proper management, can pose significant environmental and public health issues [ 3 ]. Consequently, much research has been devoted to finding sustainable ways to recycle and reuse rice bran, most notably as a functional and nutritional food ingredient, by leveraging on the many bioactive compounds, such as phenolics, tocotrienols, tocopherols, and γ-oryzanol [ 2 ]. Moreover, rice bran is also a rich source of dietary fibre, comprising 8.5% arabinoxylans, which acts as a prebiotic for promoting gut health through stimulating beneficial gut microbial species to improve immune health and prevent chronic disease [ 4 , 5 ].…”

Bioprocessed Black Rice Bran Potentiates the Growth Inhibitory Activity of an Immune Checkpoint Inhibitor against Murine Colon Carcinoma

“…Indeed, Suttiaporn et al [2] demonstrated the anti-leukemic cell activity of phytosterols and triterpenoids isolated from black rice bran. A review by Tan et al [3] suggests that bioactive compounds from rice bran waste produced during the milling process, which removes the bran and germ and leaves the starchy endosperm, can benefit nutrition and health. Although thermal cooking decreases anthocyanin content and antioxidative activity, it does not affect the anti-inflammatory activity of black rice [4].…”