Enzymatic proteins with good sensory properties and functional characteristics were obtained from Tilapia skin. Enzymatic proteins were prepared from Tilapia skin by Alcalase. Hydrolysis degree was controlled by pH-stat method. Effect of hydrolysis degree on the yield of enzymatic protein, solubility, emulsifying properties and sensory properties of protein power were studied. The results showed that in the range of the experiment(DH=2%~10%), the yield of hydrolyzed protein and purity protein powder increased, and solubility and emulsifying properties of hydrolyzed protein powder decreased with increased degree of hydrolysis. Sensory evaluation results showed that,for different samples, significant different fishy smell and color was observed, and insignificant bitterness was tasted. For protein powder of 2% hydrolysis degree, the highest solubility and emulsifying properties were obtained with corresponding high impurity and inferior sensory quality. Comparatively, the best sensory properties was obtained for hydrolyzed protein of 5% hydrolysis degree with heat processing before enzymatic hydrolysis. High purity hydrolyzed protein with good sensory properties and functional characteristics could be
prepared by controlling of the lower hydrolysis degree (e.g. DH=5%) from Tilapia skin. |