2024 Technical Program
Protein and Co-Products
Sustainable Protein
Nikitha Modupalli
Post Doctoral Research Associate
University of Arkansas
Fayetteville, Arkansas, United States
Mahfuzur Rahman
Assistant Professor
University of Arkansas
Fayetteville, Arkansas, United States
The USA produces approximately 18 million cwt of rice bran containing 12% protein every year, and this resource is highly underutilized as a source of plant protein. To popularize rice bran protein (RBP) in the alternative plant protein market, this study aims to improve RBP extraction yield and functionality for food applications. The conventional method of alkaline extraction (pH 9.0) and isoelectric precipitation proves to be less effective in terms of both yield and quality of RBP. This study explores the suitability of acidic extraction at pH 2.0 and alkaline (pH 9.0) + acidic (pH 2.0) extraction (AA) followed by isoelectric precipitation at pH 4.5 (IEP) and IEP + heat coagulation at 90℃ for better yield and protein functionality. The alkaline + acidic extraction followed by IEP + heat coagulation (IH) yielded 78.18% protein isolate, while alkaline and acidic extractions followed by IH resulted in comparatively lower yields of 58.18% and 18.18%, respectively. This shows that heat coagulation following IEP can increase the yield of RBP significantly. The alkaline extraction followed by IH showed a purity of 87.14%, whereas 56.69% for alkaline + acidic extraction with IH precipitation. The IH precipitated samples of alkaline extraction also exhibited better solubility (%) and water holding capacity of 60% and 240%, respectively. Therefore, heat coagulation coupled with IEP can enhance RBP yield and functionality. The evaluation of other functional attributes, such as emulsification and foaming properties, is underway. Additionally, further studies are being conducted on the role of atmospheric cold plasma on the functional properties of extracted rice protein.