Optimization of rice bran stabilization by infrared‐vacuum process and storage stability

Rice bran as a potent ingredient: unveiling its potential for value-added applications

Rice bran production significantly contributes to global environmental deterioration, yet its potential remains underutilized. This review discusses the nutritional composition, bioactive compounds, health benefits, limitations, and potential application of rice bran in both food and non-food sectors. While minor variations exist between pigmented and non-pigmented rice bran, the former is abundant in phytochemicals, which offer therapeutic benefits. The primary limitations hindering rice bran's food application include rancidity, toxic heavy metals, and antinutrients. Effective stabilization is crucial to extend rice bran's shelf life. Despite these challenges, rice bran holds significant potential for value-added products. Hence, its rich composition and diverse applications underscore its importance as a valuable resource for sustainable production practices.

Rice Bran Extraction and Stabilization Methods for Nutrient and Phytochemical Biofortification, Nutraceutical Development, and Dietary Supplementation

Rice is a global staple food crop for nearly half of the world's population. Rice bran along with the germ are essential components of whole-grain rice and have immense potential for enhancing human nutrition. Rice bran has a unique composition and distinct requirements for processing before it can be consumed by humans when compared with other cereal brans. The comprehensive overview and synthesis of rice bran processing include extending the shelf life for functional food product development and extraction of bioactive components. This narrative review highlights established and innovative stabilization approaches, including solvent extraction and enzymatic treatments, which are critical methods and technologies for wider rice bran availability. The nutrient and phytochemical profiles of rice bran may improve with new cultivar development and food-fortification strategies. The postharvest agricultural practices and processing techniques can reduce food waste while also supporting growers to produce novel pigmented cultivars that can enhance nutritional value for human health.

Rice Bran: From Waste to Nutritious Food Ingredients

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.

High Value Compounds and Bioactivity of Rice Bran, Rice Bran Protein: A Review

Rice bran and rice bran protein are important sources of minerals, energy, and vitamins. Other bioactive compounds are abundantly available to exert therapeutical activity. Healthpromoting activities of high-value compounds of rice bran were significant, as observed in recent studies. A variety of bioactive components present in rice bran and rice bran extract are responsible to exhibit therapeutical potential like chemopreventive, cardioprotective, hepatoprotective, immunomodulatory, neuroprotective, and lipid-lowering activity. Several bioactivity representative compounds like γ-oryzanol, ferulic acid, caffeic acid, tricin, protocatechuic acid, vanillic acid, coumaric acid, phytic acid, isoferulic acid, gallic acid, γ-amino butyric acid, sinapic acid, saturated and unsaturated fatty acids, vitamin E complexes, β-sitosterol, stigmasterol, campesterol, cyanidin-3-glucoside, peonidin-3-glucoside, quercetin, rutin, kaemferol, β-carotene, lutein, vitamin B and lycopene are known to display significant health benefits. The bioactive components produced therapeutical effects by regulation of different mechanisms like increasing faecal excretion, reducing oxidative stress, reducing the level of malondialdehyde (MDA), regulation of NF-kb activation, reduction of proinflammatory cytokines production, suppression of SREBP-1, reduction in the expression of anti-apoptotic protein Bcl-2, elevated the expression of proapoptotic protein Bax, up-regulating P53 expression and suppressing COX-2. Several research engines like PubMed, google scholar, science direct, etc. were used to collect the data on the mentioned keywords. Recent scientific works were included in this article. In this review paper, we profiled the high-value compounds and focused on their antioxidant, anti-hyperlipidemic, antidiabetic, and anticancer activity with their possible mechanism of action.

The Effects of Thermal Treatment on Lipid Oxidation, Protein Changes, and Storage Stabilization of Rice Bran

Rice bran is a nutrient-rich and resource-dense byproduct of rice milling. The primary cause of rice bran utilization limitation is oxidative deterioration and inadequate storage facilities. Improving stability to extend the shelf-life of rice bran has thus become an utmost necessity. This study aimed to stabilize raw fresh rice bran (RB) by using dry heat methods at 120 °C (233, 143, and 88 min) and 130 °C (86, 66, and 50 min). The results indicated that after dry heat pretreatment, peroxidase levels were at 90%, and the storage stability of dry-heat-stabilized RB was better. However, with an increase in treatment temperature and time, the peroxidase activity improved while the lipase activity decreased to a certain extent without significant changes. The total saturated and unsaturated fatty acids were significantly unchanged during storage, while oleic/linoleic acid increased substantially by 1% at 120 °C for 88 min. The increase in treatment time and temperature was beneficial in controlling the fatty acid values. However, extended treatment time caused an increase in the peroxide value and MDA. The essential and non-essential amino acid ratios, which evaluate a protein's nutritional value, remained relatively stable. The essential subunit of rice bran protein was not affected by the temperature and time of dry heat treatment and storage time.

Transcriptomics View over the Germination Landscape in Biofortified Rice

Hidden hunger, or micronutrient deficiency, is a worldwide problem. Several approaches are employed to alleviate its effects (e.g., promoting diet diversity, use of dietary supplements, chemical fortification of processed food), and among these, biofortification is considered as one of the most cost-effective and highly sustainable. Rice is one of the best targets for biofortification since it is a staple food for almost half of the world’s population as a high-energy source but with low nutritional value. Multiple biofortified rice lines have been produced during the past decades, while few studies also reported modifications in germination behavior (in terms of enhanced or decreased germination percentage or speed). It is important to underline that rapid, uniform germination, and seedling establishment are essential prerequisites for crop productivity. Combining the two traits, biofortified, highly-nutritious seeds with improved germination behavior can be envisaged as a highly-desired target for rice breeding. To this purpose, information gathered from transcriptomics studies can reveal useful insights to unveil the molecular players governing both traits. The present review aims to provide an overview of transcriptomics studies applied at the crossroad between biofortification and seed germination, pointing out potential candidates for trait pyramiding.