Department of Food Science and Technology, Tokyo University of Marine Science and Technology, Konan 4-5-7, Minato-ku, Tokyo 108-8477, Japan.
General Foods Laboratory, Natori Co., Ltd, Toshima 8-3-3, Kita-ku, Tokyo 114-0003, Japan.
Food Res Int. 2017 Jul;97:231-239. doi: 10.1016/j.foodres.2017.04.018. Epub 2017 Apr 18.
To clarify why mantle meat from Japanese common squid (Todarodes pacificus) dried products discolor dramatically when processed by air-drying, the role of endogenous protease(s) on browning during the processing of dried squid products was studied. The involvement of endogenous protease(s) in the generation of Free Amino Acids (FAAs) participating in the Maillard reaction was characterized. The browning and myosin heavy chain degradation during air-drying were obviously mitigated by the addition of metalloprotease inhibitors, especially EGTA and 1,10-phenanthroline, followed by serine proteinase inhibitor, especially PMSF. The amount of total FAAs in dried products increased by only 0.17% with the addition of 1,10-phenanthroline and 5.0% with added EGTA. In autolysis models, protein autolysis was almost completely inhibited by 1,10-phenanthroline. The addition of, 1,10-phenanthroline inhibited the increase in total FAAs including arginine (Arg), followed by EGTA and PMSF. The results indicated that endogenous metalloproteases and serine proteases might influence the generation of FAAs including Arg, and contribute to product discoloration during air-drying.
为了阐明日本真鱿（Todarodes pacificus）干制品在风干过程中 mantle 肉为何会剧烈变色，研究了内源性蛋白酶（s）在干鱿鱼制品加工过程中褐变的作用。研究了内源性蛋白酶（s）在生成参与美拉德反应的游离氨基酸（FAAs）中的作用。通过添加金属蛋白酶抑制剂，特别是 EGTA 和 1,10-菲啰啉，以及丝氨酸蛋白酶抑制剂，特别是 PMSF，明显减轻了风干过程中的褐变和肌球蛋白重链降解。添加 1,10-菲啰啉可使干制品中总 FAAs 仅增加 0.17%，添加 EGTA 则可增加 5.0%。在自溶模型中，1,10-菲啰啉几乎完全抑制了蛋白质自溶。添加 1,10-菲啰啉抑制了包括精氨酸（Arg）在内的总 FAAs 的增加，随后是 EGTA 和 PMSF。结果表明，内源性金属蛋白酶和丝氨酸蛋白酶可能影响包括 Arg 在内的 FAAs 的生成，并导致风干过程中产品变色。
