Optimization of Cooking Process of Skipjack Tuna Tsukudani and Composition Analysis of Seasoning Solution
ZHANG Jianyou, FEI Lifeng, SUN Lei, WANG Zhen, Lü Fei, DING Yuting
1.Key Laboratory of Marine Fishery Resources Exploitment and Utilization of Zhejiang Province, College of Food Science and Technology, Zhejiang University of Technology, Hangzhou 310014, China; 2.National R&D Branch Center for Pelagic Aquatic Products Processing (Hangzhou), Hangzhou 310014, China; 3.Collaborative Innovation Center of Seafood Deep Processing, Dalian Polytechnic University, Dalian 116034, China
Abstract:The optimal cooking process of skipjack tuna tsukudani was determined based on color difference, texture properties and sensory evaluation, and its nutritional quality was evaluated by measuring its reducing sugar and protein content and pH value, etc. Furthermore, the changes of reducing sugar and amino nitrogen content in the seasoning solution were analyzed. The results showed that the sensory score of tsukudani prepared by boiling with gradient sugar concentrations was highest (92.5 points), and the contents of reducing sugar and non-protein nitrogen in it were high (6.22 and 3.63 g/100 g, respectively). The content of salt soluble protein in tsukudani prepared by boiling with gradient (product A) and non-gradient sugar concentrations (product B) was 15.18 and 14.65 g/100 g, respectively, significantly higher than that in tsukudani prepared by immersing the fish in the seasoning solution (product C). In addition, the content of alkali soluble protein in product A was 43.22 g/100 g and significantly higher than those in products B and C, indicating that the protein content in product A, which had low nutrient losses and the best flavor quality, changed little after gradient sugar tsukudani. The texture quality of product C was better with good elasticity and chewainess. There was no significant difference in pH value among the three products. The reducing sugar in product A provided sufficient carbonyl compounds for the Maillard reaction, which promoted the formation of good color and flavor, and the small change in the content of amino nitrogen verified that product A had good nutritional quality. The results collectively showed that the quality of product A was best, which had good color, protein nutritional quality and texture.