Functional properties of protein hydrolysates from Riceberry rice bran. (16th February 2016)

• Record Type: Journal Article
• Authors: Thamnarathip, Parichart; Jangchud, Kamolwan; Jangchud, Anuvat; Vardhanabhuti, Bongkosh
• Is Part Of: International journal of food science & technology. Volume 51:Number 5(2016)
• Page Start: 1110
• Page End: 1119
• Publication Date: 2016-02-16
• Subjects: Emulsification properties -- functional properties -- heat stability -- rice bran protein hydrolysate -- solubility -- zeta potential; Food industry and trade -- Periodicals; 664
• DOI: 10.1111/ijfs.13071
• Languages: English
• ISSNs: 0950-5423

Abstract

Summary: Protein hydrolysate from pigmented Riceberry rice bran has great potential to be used in food products due to its protein content and antioxidative activities. In this study, characteristics, solubility, heat stability and emulsification properties of protein hydrolysates from the bran fraction of two rice cultivars, commercial rice bran (CBH) and Riceberry bran (RBH), were investigated. Both CBH and RBH showed the lowest solubility near their isoelectric point between pH 2 and 3. Solubility of RBH increased with increasing pH as the hydrolysates became more negatively charged; however, solubility of CBH was less dependent on pH. Heating did not significantly affect solubility of both hydrolysates which could be due to reduced aggregation of low‐molecular weight peptides and/or the exposure of charged and polar groups after hydrolysis. Oil‐in‐water emulsions stabilised by RBH were more stable compared to those stabilised by CBH. Maximum stability was achieved with RBH at pH 6 where no creaming was observed after 14 day storage. Higher stability could be due to increased surface protein coverage, more negative charge and higher viscosity of RBH‐stabilised emulsions. In addition, higher carbohydrate content and the presence of flavonoid could also contribute to an increase in stability. These results can be applied in food products using rice bran protein hydrolysate as nutritional ingredients. Abstract : Stability of oil in water emulsions stabilized by bran protein hydrolysates from Riceberry rice or commercial rice. O/W emulsions contained 2.5% w/w and 0.5% w/w protein and were at pH 2 to 9.