Flavored-functional protein hydrolysates from enzymatic hydrolysis of dried squid by-products: Effect of drying method

Abstract Dried squid head is an abundant–low value by product from dried squid snack industry. The head is consisted of high protein content with the abundant sweet-umami amino acid, glutamic acid (7.45 mg/100 mg). The major volatile compounds found are trimethylamine and toluene along with the 15 important compounds exhibited dried squid flavor. Enzymatic hydrolysis with Flavourzyme ® was performed at the optimal pH and temperature in order to produce flavored-functional protein hydrolysate. The supernatant was collected at 0, 30, 60, 90, 120, 150, 180 and 210 min of hydrolysis. The sweet-umami hydrolysate solution with the highest liking score at 6.64 was obtained after 180 min of hydrolysis. This sample was subjected to dry using freeze drying and foam-mat drying and investigated the changes of flavor compounds and functional properties. The freeze dried sample had umami taste and light brown color, and possessed the various types of volatile compounds. It contained protein at 76.42%, and EAI at 22.00, while the foam-mat dried sample had the highest ESI (15.27) and FS (29.87). The antioxidant property of the freeze dried sample (ABTS scavenging activity at 14.77 mg/g, FRAP scavenging activity at 5.93 mmol Fe 2 SO 4 7H 2 O/g and DPPH scavenging activity at 19.51%, respectively) was higher than that of the foam-mat dried sample. Hence, it could be used as flavored-functional ingredient in foods.