Optimization of Extraction Process Parameter for Rice Bran Protein Concentrate and its Utilization in High Protein Biscuit Formulation

In the present study rice bran protein concentrate (RBPC) was extracted from defatted rice bran by alkali extraction method and the extracted protein concentrate was characterized and utilized in biscuit production. Protein concentrate was extracted from rice bran at different rice bran water ratio (25.86-54.14) and solution pH (8.09-10.91). The extraction parameters were optimized by response surface methodology. Optimum conditions for protein concentrate extraction ratio were 1:40.77 bran/water and 9.55 pH of solution. At the optimum conditions the extraction yield of protein concentrate was 11.76% and protein content was 36.29% where native rice bran contained 20.78% protein. RBPC contained most of essential amino acids except tryptophan and phenylalanine, among them arginine was the highest 2.27 mg/100g and the lowest was histidine 0.59 mg/100g. RBPC also contained non-essential amino acid like aspartic acid, serine, glutamic acid, alanine, glycine and tyrosine. The emulsifying capacity, emulsion stability, water absorption capacity, bulk density and oil absorption capacity of RBPC were 56 percent, 36 min, 3.02 g/g, 0.49 g/ml and 1.72 g/g respectively. A 5% rice bran protein concentrate supplemented biscuits upgrade the total protein content in biscuits from 7.54 to 9.13. Therefore, utilization of RBPC can be beneficially achieved through formulation of protein enriched biscuits with enhanced nutritional value especially for malnourished or undernourished people.