Abstract
Muscle softening or mushiness of shrimp occurs generally during storage and distribution in ice. This
phenomenon is caused by the muscle protein degradation due to the proteolytic activity. The purpose of this
study was to understand quality improvement for P. vannamei by soybean powder. Soybean powder
improved texture and yield of heat-treated P. vannamei. Based on inhibitor study, SBTI (soybean trypsin
inhibitor) showed the highest inhibition at pH7.0 and pH9.0, while Pepstatin A exhibited the higher
inhibition at pH3.0. Autolysis in P. vannamei meat could be inhibited mainly by SBTI and partially by a
cysteine protease inhibitor, and EDTA at neutral and alkaline pH values.
