89B-17 |
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J. S. KIM, Division of Marine Bioscience/Institute of Marine Industry, Gyeongsang National University, 445 INPYEONG, TONGYEONG, KYEONGNAM, 650-160, South Korea and J. W. Park, Dept. of Food Science and Technology, Oregon State Univ. Seafood Laboratory, 2001 Marine Drive #253, Astoria, OR 97103. Today consumers demand safe foods with nutritionally or functionally enhanced characteristics. Protein hydrolysates have various functional properties, such as antioxidation and angiotensin I converting enzyme (ACE) inhibition. Protein hydrolysates like soy sauce and fish sauce are prepared by long fermentation periods at high salt concentration, whereas enzymatic fish hydrolysate results in a bitter taste. Enzymatic hydrolysate, however, can be prepared from animal gelatin in a few hours without a bitter taste. Solid byproducts from surimi processing contain significant amounts of collagen and with recent outbreaks of BSE, fish gelatin is receiving attention as a consumer-friendly resource of protein hydrolysates. Our objectives were to examine the proteolytic conditions of gelatin from surimi byproduct based on its functional characteristics and to prepare gelatin sauce with functional components. Skin collected from a deboning machine and tendon/connective tissues from a refiner were isolated for evaluation. For digestion of fish gelatin, three proteases, Alcalase, Neutrase and Flavozyme were used. Gelatin was dissolved in water, hydrolyzed with protease at a ratio of protein substrate to enzyme (100 to 1, w/w) for 1-6 h in a batch reactor before heating (98 C, 10 min). The resulting hydrolysate by a single enzyme or combination of two was assayed for hydrolysis degree, antioxidative and ACE inhibitory activities, molecular weight, amino acid, and other functional characteristics. Gelatin hydrolysate by the combination of Flavozyme and Neutrase was the highest in hydrolysis degree, antioxidative and ACE inhibitory activities, and the major molecular weight of the hydrolysate was 1.5 kDa and 4.5 kDa. Gelatin sauce with functional components was prepared by dissolving 100 g salt in 1000 mL of the hydolysate treated by the combination of Flavozyme and Neutrase, which resulted in no bitter taste. These results indicate that gelatin sauce can be a good food condiment with functional characteristics.
Session 89B, Aquatic Food Products: Surimi, gels and by-products
2005 IFT Annual Meeting, July 15-20 - New Orleans, Louisiana |