An update on the processing of high‐protein rice products

Abstract

The component of protein in rice, at 7-9% by weight, is relatively low, but the total amount of rice protein potentially available is significant because the production of rice worldwide, at 380 million tons annually, is huge. Rice proteins are recognized as nutritional, hypoallergenic, and healthy for human consumption, and rice protein products have been in demand in recent years. However, because of difficulties in the processing, rice protein products, particularly high-protein content ones, have not been readily available. Two of the main sources of rice protein, rice bran and, to a lesser extent, broken rice kernels, have been under-used and under-priced. This report provides an update on the processing of these sources for rice proteins. Methods of protein processing are highlighted including the traditional alkaline extraction, enzyme-assisted extraction, and the novel uses of physical treatment prior to water extraction. Also discussed are effects of processing on the functional and nutritional properties of rice protein.

Physicochemical properties and molecular structures of Korean waxy rice starches

“…Endosperm of rice grain is composed of protein body between starch granules; however, most of protein bodies are contained glutelin, which is soluble in alkaline solution. Due to isolated starch using alkaline solution, the protein content of isolated starch is very trace (23). The moisture contents ranged from 6.55-7.18%; the ash and crude protein contents of Nunbora starch were higher than those of other starches (p<0.05).…”

Effect of succinylation on functional and morphological properties of starches from broken kernels of Pakistani Basmati and Irri rice cultivars

“…Starch is the major component of rice kernel and is almost 90% of the total kernel weight (Shih, 2003). Rice starch is a combination of novel characteristics.…”

Physical and flow properties of rice protein powders

“…Although the protein content of rice is relatively low, its total food protein production per hectare is second only to that of wheat among cereals (Childs, 2004). Rice flour from milled rice or broken rice kernels and rice bran represent the two main sources of rice proteins, and various treatments have been evaluated for their extraction, including alkaline, enzymatic and physical methods (Fabian and Ju, 2011;Shih, 2003). Rice proteins are generally regarded as hypoallergenic (Helm and Burks, 1996) and rice has been estimated to have a higher protein digestibility and biological value compared to other cereals (i.e., wheat, corn, barley, millet and sorghum), the latter being due to the higher content of lysine (Eggum, 1979), i.e., the first limiting amino acid among cereal proteins (Young and Pellett, 1994).…”