Brown rice

About: Brown rice is a research topic. Over the lifetime, 8180 publications have been published within this topic receiving 81079 citations.

Substitution of wheat flour with wholegrain flours affects physical properties, sensory acceptance, and starch digestion of Chinese steam bread (Mantou)

Abstract: This study investigated the effects of partial replacement of wheat flours with wholegrain flours on the physical characteristics and starch digestion of Mantou. Mantou was made with wheat flours partially substituted with brown rice or oat flours at the levels of 10% or 30%. Physical characteristics, including adhesiveness, hardness and springiness, of Mantou were significantly affected with substitution due to the disruption of dough structure. SEM observation evidenced that wholegrain incorporation resulted in discontinuous and irregular structure of Mantou. Sensory evaluation found that lower wholegrain incorporation of Mantou with lighter color exhibited higher score. Correlation analysis between physical parameters and sensory evaluation showed that appearance attraction negatively correlated to b* (yellowness-blueness) value. Compared with Mantou without substitution, wholegrain postponed starch digestion. Oat exerted particularly stronger effect because hydrolysis index (HI) decreased from 121 to 74 and 67 as the incorporation brown rice and oat at the level of 30%, respectively. In conclusion, our results revealed that wholegrain levels affected physical characteristics, sensory acceptance and nutritional quality of Mantou. Although the acceptance score of Mantou incorporated with oat flour was around 5 (neither dislike nor like), oat incorporation with a lower HI may provide an alternative choice for health concern.

Brown rice-specific γ-oryzanol as a promising prophylactic avenue to protect against diabetes mellitus and obesity in humans.

Abstract: Chronic overconsumption of animal fats causes a variety of health problems, including diabetes mellitus and obesity. Underlying molecular mechanisms encompass leptin resistance, a decrease in rewarding effects of physical activities, xanthine oxidase-induced oxidative stress in vasculature and peripheral tissue, impaired activation of incretin signaling, deviation in food preference, and dysbiosis of gut microbiota. Based on our clinical observation that daily intake of brown rice effectively ameliorates bodyweight gain, impaired glucose tolerance/insulin resistance and dependence on fatty foods in obese, prediabetes men, a line of research on brown rice (rice bran)-derived γ-oryzanol in mice experiments, cultured cells and human clinical trials is underway in our laboratory. Our works in mice showed that γ-oryzanol, an ester mixture of ferulic acid and several kinds of phytosterols, acts as a molecular chaperone, thereby attenuating the strong preference for animal fats through suppression of endoplasmic reticulum stress in the hypothalamus. In pancreatic islets from both high-fat diet-induced and streptozotocin-induced diabetic mice, γ-oryzanol ameliorates endoplasmic reticulum stress and protects β-cells against apoptosis. Noticeably, γ-oryzanol also acts as a potent inhibitor against deoxyribonucleic acid methyltransferases in the brain reward system (striatum) in mice, thereby attenuating, at least partly, the preference for a high-fat diet through the epigenetic modulation of striatal dopamine D2 receptor. Because dopamine D2 receptor signaling in the brain reward system is considerably attenuated in obese humans and rodents, γ-oryzanol might represent a unique property to ameliorate both hedonic and metabolic dysregulation of feeding behavior, highlighting a promising prophylactic avenue to protect against metabolic derangement.

Physicochemical properties of germinated brown rice (Oryza sativa L.) starch

Abstract: Physicochemical properties of white rice (WR), brown rice (BR) and germinated brown rice (GBR) starches from a mixed variety of MR219 and MR220, commonly consumed Malaysian varieties, were compared in this study. The granular size of the starch particles, measured using scanning electron microscope (SEM), varied from 2 to 8 µm for all starches and appeared in polyhyedral shapes. Amylose content in WR, BR and GBR as analysed using colorimetric method was found to be 25.77, 23.83 and 21.78%, respectively. The amylose content of GBR was significantly lower than that of WR or BR. Results also show that germination affected gelatinization and pasting properties. This study has profound implications for future studies on functional properties of GBR and may help us understand what role changes in physicochemical properties, brought about by germination, play in determining functional effects.

Ohmic heating for cooking rice: Electrical conductivity measurements, textural quality determination and energy analysis

Abstract: In this study, an innovative technique, namely ohmic heating was applied in rice cooking and compared with conventional method using electric rice cooker Four types of rice samples including white rice of two varieties (KDML105 and Sao Hai), brown rice and germinated brown rice of one variety (KDML105) were used Electrical conductivities of mixtures between rice samples and 01 M salt solution at various ratios were measured Empirical models were developed for predicting electrical conductivities of rice samples as a function of temperatures Textural properties of cooked rice samples and energy consumption were compared between ohmic and conventional cooking methods The purposes of this work were to (1) study the possibility of applying ohmic method in rice cooking and (2) compare between cooking rice by ohmic and conventional method The results revealed that it is possible to apply ohmic method for cooking all rice samples by using 01 M salt solution in the mixtures The electrical conductivities of white rice (KDML105), white rice (Sao Hai), brown rice and germinated brown rice (KDML105) mixtures were 0246–0900, 0375–1005, 0617–1370 and 0485–1182 S/m respectively The rice cooked by ohmic method had significantly different textural properties from that cooked by electric rice cooker The magnitude of difference depended on the rice types The electrical energy consumption of ohmic cooking system was approximately 73–90% of energy required for conventional rice cooker

Ethanol production by Zymomonas mobilis CHZ2501 from industrial starch feedstocks

Abstract: The optimal conditions of ethanol fermentation process by Zymomonas mobilis CHZ2501 were investigated. Brown rice, naked barley, and cassava were selected as representatives of the starch-based raw material commercially available for ethanol production. Considering enzyme used for saccharification of starch, the ethanol productivity with complex enzyme was higher than glucoamylase. With regards to the conditions of saccharification, the final ethanol productions of simultaneous saccharification and pre-saccharified process for 1 h were not significantly different. The result suggested that it is possible for simultaneous saccharification and fermentation as a cost-effective process for ethanol production by eliminating the separate saccharification. Additionally, the fermentation rate in early fermentation stage was generally increased with increase of inoculum volume. As the result, optimal condition for ethanol production was simultaneous saccharification and fermentation with complex enzyme and 5% inoculation. Under the same condition, the volumetric productivities and ethanol yields were attained to 3.26 g/L·h and 93.5% for brown rice, 2.62 g/L·h and 90.4% for naked barley, and 3.28 g/L·h and 93.7% for cassava, respectively.