Effect of Water Activity-Lowering Agents on the Quality of Semi-Dried Blunt Snout Bream
FANG Xiaoyu, XUE Yike, XIONG Shanbai, YIN Tao, LIU Ru, YOU Juan
1. College of Food Science and Technology, Huazhong Agricultural University, Wuhan 430070, China; 2. National R&D Branch Center for Conventional Freshwater Fish Processing (Wuhan), Wuhan 430070, China
Abstract：The effect of different water activity (aw)-lowering agents on the water state and quality of semi-dried blunt snout bream was studied by measuring its aw, water state, total viable counts (TVC), yeast count, total volatile basic nitrogen (TVB-N) content, thiobarbituric acid reactive substances (TBARS) value, and sensory scores. The results showed that the type and amount of aw-lowering agents had a significant impact on the aw, water state and physicochemical indicators of semi-dried blunt snout bream, the latter effect being more pronounced than the former one. Trehalose, sorbitol and glycerol reduced the aw, glycerol being the most effective among the aw-lowering agents. When 6% glycerol was added, the aw was reduced from 0.917 to 0.873. With increasing amounts of added trehalose, sorbitol and glycerol, the T22 significantly decreased (P < 0.05), but the T23 did not significantly change. The proportion of immobilized water increased significantly (P < 0.05), whereas the proportion of free water decreased significantly (P < 0.05). Relative to the control group, the TVC, yeast count, TVB-N content, and TBARS value were significantly reduced (P < 0.05) with increasing addition of aw-lowering agents, and the optimal values of these parameters were obtained with the addition of 6% glycerol. To sum up, the addition of aw-lowering agents could effectively reduce water freedom and fluidity and slowed down the quality deterioration of semidried blunt snout bream.
2024, Vol. 38 
