Submitted to: Agricultural Engineering International Conference
Publication Type: Proceedings
Publication Acceptance Date: December 11, 2010
Publication Date: January 20, 2011
Citation: Shih, F.F. 2011. An update on the use of rice in value-added food products. Meeting Proceedings. Agricultural Engineering International Conference Proceedings. 3:45-53. Interpretive Summary: In addition to the polished white rice, various by-products, including rice bran and broken rice, are generated during the milling of rice. In spite of plentiful supply and high nutrition, rice bran, and to a lesser extent, broken rice kernels, are under-valued and under-utilized. The present review focuses on selected examples in developing methods to promote the use of and add value to these by-products. Rice products with up to 91% protein were prepared, which could be used in health food and infant food formulations. Rice flour and its starch component was modified for improved functional properties, and then used to prepare batters that compared favorably to traditional wheat batters in general qualities, but absorbed much lower oil during frying.
Technical Abstract: Because of the huge quantity of rice produced annually, milled-rice co-products; such as, rice flour, rice bran, rice wax, and rice hull are plentiful and readily available. These co-products could be valuable sources of food ingredients, but they have been vastly under-utilized. This is a report summarizing research efforts at the Southern Regional Research Center (SRRC, New Orleans, LA, USA) that are dedicated to convert rice and its co-products into value-added food products. Rice bran and rice flour contain rice proteins, at about 20% and 8%, respectively. When treated with carbohydrate-hydrolyzing enzymes, they yielded high-protein products; which are nutritious, hypoallergenic, and widely used in health food and baby food formulations. Rice flour contains more than 90% rice starch (RS), which is gluten-free and has unique physico-chemical characteristics. Functional properties of RS were modified to suit the needs for a wide range of food applications. The addition of small amounts of phosphorylated RS esters, or pregelatinized rice flour, to rice batters was found to impart to the resulting fried product superior sensory characteristics, and a lowering of the oil-uptake by up to 50%, as compared with those of the traditional wheat counterparts. Similarly, other rice-based low oil-uptake and gluten-free fried foods; such as, cake donuts, and pancakes were also developed. Treatment of RS with octenylsuccinic anhydride (OSA) produced OSA-RS esters with balanced hydrophilic-hydrophobic characteristics, useful as emulsifying agent for the encapsulation of lypophilic compounds.