Microwave (MW) Energy in Enzyme Deactivation: Stabilization of Rice Bran from Few Widely Consumed Indigenous Rice Cultivars (Oryza sativa L.) from Eastern Himalayan Range

Abstract

Rice bran which is an industrial cereal processing waste/by-product has great economic potential towards developing nutraceuticals and functional foods to combat life style related diseases because of several health beneficial biomolecules and micronutrients present in it. Utilization of food processing waste or byproducts through sustainable development into new food has been regarded as a potential thrust area in recent years. To exploit rice bran commercially in this area, it is of utmost importance to stabilize freshly milled rice bran to enhance its shelf-life as it develops rancidity within few hours of its milling due to the action of lipase and lipoxygenase (LOX) enzymes present in it. Hence stabilization of freshly milled rice bran through inactivation of these enzymes has been a subject of much interest to food chemistry researchers. Considering the importance of rice bran for its potential use as nutraceuticals, food supplement and functional food, coupled with green technology associated with microwave (MW) energy in food science and technology, we report here an expedited and convenient stabilization process of rice bran with special reference to some of the indigenous rice cultivars grown abundantly in North East India situated in the Eastern Himalayan Range, which is one of the global hot spots of biodiversity. The work further highlights the efficacy of MW energy in deactivating lipase and lipoxygenase enzymes present in rice bran to give it longer shelf-life for its potential exploitation as nutraceuticals and food supplements. Keywords: Cereal processing waste, rice bran, microwave, stabilization, lipase, lipoxygenase, nutraceutical, functional food.