A Predictive Model on Moisture and Yield Loss in Phosphate-Treated, Cooked Tiger Shrimp (Penaeus monodon)

Physical properties of shrimp are economically important, and affected by size of shrimp, pre-treatments, used cooking time and temperature, cooling methods and other processing conditions during thermal processing. Phosphates are commonly used in shrimp industryto reduce moisture and yield losses in processing. Isothermal experiments were conducted to measure the changes in yield loss and moisture content of shrimp after treatment with sodium tripolyphosphate (STP) solutions, 3-cooking temperatures (75, 85,95), 3-cooking times (3.4, 2.1, 1.6 mins), and 2-cooling methods (direct ice slush and indirect ice slush). All these processing conditions were found to have a significant effect on yield and moisture losses (p < 0.001). The experimental data observed for yield and moisture loss as affected by cooking temperature/time, and STP solutions were fitted to nonlinear polynomial equations. These data were used in a mathematical model of temperature distribution to predict the yield loss of shrimp in thermal processing. The model predictions and experimental results showed close agreement. This mathematical model can be used to determine the yield loss of STP-treated shrimp for different processing conditions provided that the experimental yield loss data for different conditions are available.