Optimization for Extracting Iraqi Rice Bran Proteins Cultivar Yasmin and study some of Its Functional Properties
Study of the chemical composition of whole rice bran, and defatted rice bran for Iraqi rice cultivar Yasmine, which was obtained from province of Najaf, showed that the moisture, ash, fat, carbohydrates and protein were 15.8%, 7.9%, 23.5%, 41.1% and 11.7% respectively, for full bran, and 20.9%, 11.2%, 5.5%, 44.25% and 18.15% respectively, for defatted bran. The results of this study showed that the best conditions in the preparation of protein extract from defatted rice bran were by extraction with distilled water after equalized pH to 11 with a ratio bran: water of 1:4 (w : v ) for 60 min at agitation speed of 600 rpm.min-1. At these conditions protein percentage were 59.4%. This study revealed that of solubility, emulsifying activity, emulsion stability and foaming capacity and stability of the protein extracted from the defatted rice bran, were highest at pH 11, compared with other pH values with the values of 74.8% , 0.637, 68.8 min and 47% respectively, while the lowest was at pH 4 with the values of 19.3%, 0.057,21.1 min and 7% respectively. The study also showed that the holding capacity of water and fat of the protein concentrate from defatted rice bran was 2.3 ml water . g -1 protein and 2.1 ml oil. g -1 protein respectively.