Optimization for Extraction Proteins from Pulp of Watermelon Seed

The study was carried out in the laboratories of the Faculty of Agriculture / University of Tikrit to the period 2017/11/7 - 1/5/2018. The study of watermelon seed pulp the local variety, to obtain protein isolates of the graft after removal of fat. The results showed chemical composition of the imported and local variety the percentage of moisture was 2.9%, 2.5%, ash 4.2%, 3.8%, fat 41%, 40.2%, carbohydrates 19.4%, 18.5% respectively. The result show that the percentage at important and locally were 32.5% and 35%, respectively. The watermelon seeds (imported and local) showed that the moisture 4.2% and 4%, ash 1.9% and 2.5%, fat 23.5%, 21.8%, carbohydrates 49.2%, 48.4%, protein 21.2%, 23.3% respectively. The results of this study showed that the best conditions in the preparation of protein extract from defatted pulp of watermelon seed, were by extraction with distilled water after equalized pH to 12 with ratio bran: water of 1:10 (w:v) for 60 min ,at agitation speed of 500 rpm/min, followed by sedimentation at the isoelectric point .