Changes in taste characteristics of shellfish by cooking and during storage - Why raw cockle is not eaten ? -

研究了海扇足部分经蒸煮和4℃冷藏10天后的理化变化。在85℃下蒸煮15 s，原料样品失重27%.在冷藏10天期间，生的和熟的样品都以22- 23%的相同程度损失了它们的重量。ATP和相关化合物以及游离氨基酸的水平在生的样品比熟的样品更高，虽然前者的感官评价发现有更强的鱼腥味。原始样品在冷藏5天后开始降低ATP含量，在5天和7天后分别显示18%和42%的K'值。在冷藏过程中，原始样品的Hunter标度颜色评价的L值增加，显示其原始紫灰色逐渐消失。同时，煮熟的样品的L值在冷藏期间保持恒定。煮熟的样品的拉伸强度显着高于两个原始样品之前和之后的冷藏，表明增加韧性cooking. Effect的湿度稳定片含有甘油，纸浆，和吸收聚合物在冷藏过程中对生海扇脚也进行了检查。由于脱水，包裹在湿度稳定片材中的原始样品在4℃下储存10天期间失重32%。然而，包装样品的L值在储存期间保持恒定。ATP和相关化合物的水平和新鲜度指数的变化表明，包裹在片材中的样品上级那些没有包装。通过感官评价，包裹在片材中的样品比没有包裹的样品保持其新鲜外观的时间更长。

Physicochemical changes of Japanese cockle foot parts occurring by cooking and during cold storage at 4℃ for 10 days were examined. Raw samples lost their weight by 27 % during cooking process at 85℃ for 15 s. Both raw and cooked samples lost their weight at the same extent of 22-23 % during the cold storage for 10 days. The levels of ATP and related compounds as well as those of free amino acids were higher in raw than cooked samples, although the former sample were found by the sensory evaluation to have stronger fishy odor. Raw samples started decreasing ATP content after 5 days of the cold storage, showing the K' values of 18 and 42 % after 5 and 7 days, respectively. The L value in Hunter scale color evaluation increased during the cold storage of raw samples, revealing the gradual disappearance of its original purple grey color. Meanwhile, the L value of cooked samples remained constant during the cold storage. The tensile strength of cooked samples was significantly higher than those of both raw samples before and after the cold storage, indicating increased toughness by cooking.The effects of humidity stabilizing sheet containing glycerol, pulp, and an absorbing polymer on raw cockle foot during cold storage were also examined. The raw samples wrapped in the humidity stabilizing sheet lost their weight by 32% during storage at 4℃ for 10 days because of dehydration. However the L value of wrapped samples remained constant during storage. Changes in the levels of ATP and related compounds and in the freshness indices indicate that samples wrapped in the sheet were superior to those without wrapping. Samples wrapped in the sheet remained their fresh appearance for a longer time than those without wrapping by the sensory evaluation.