Quality improvement of high temperature-heated shrimp via pretreatment

In order to prevent the blackening and texture softening of heated shrimp, the pH was adjusted by soaking shrimps in acidic and alkali solutions, and their qualities were evaluated. The lightness of shrimps pretreated with 0.2% (w/w) citric acid and 0.05% (w/w) ascorbic acid solution increased by 20% compared to that of the control. The strength of mechanical hardness of shrimps soaked in acetic acid and phosphate solution (pH 6.0) was significantly higher (1209 g_f) compared to that of untreated shrimp (801 g_f; p<0.05), and the overall preference of texture was 0.4 points higher than that of the control in the descriptive sensory evaluation (p<0.05). In contrast, soaking in solution of pH 8 exhibited a weak texture hardening effect (855 g_f). Additionally, the hardness of the heated shrimp after soaking at an adjusted pH of 4.0 increased to 4046 g_f, but the yield based on weight decreased to 38% compared to that of untreated shrimp (70%; p<0.05).