Abstract:Effects of different saccharides, viz. sugar, inulin and trehalose on the glass transition temperature and state diagram of Penaeus vannamei meat (PV) were investigated to improve the storage stability of Penaeus vannamei meat. Moisture adsorption isotherms of PV and Penaeus vannamei meat with addition (w/w) of 10% sugar (PV-S), 10% inulin (PV-I) and 10% trehalose (PV-T) were determined at 25℃ by using the gravimetric method. Differential scanning calorimetry was employed to determine the glass transition temperature (Tg) and freezing point (TF) of samples equilibrated at various water activities. The state diagram was composed of the glass transition line and freezing curve, which were fitted according to Gordon-Taylor model and Clausius-Clapeyron model, respectively. 〖JP3〗The results showed that the adsorption behaviour of Penaeus vannamei meat (PV, PV-S, PV-I and PV-T) 〖JP〗displayed type III isotherms. The GAB model statisfactory described the adsorption behavior of PV, PV-S, PV-I and PV-T. The equilibrium moisture content of PV, PV-S, PV-I and PV-T increased with increasing water activity (aw). Moisture content of PV-S, PV-I and PV-T at a given aw was lower than that of PV. The monolayer moisture content decreased with the addition of saccharides. Tg of PV, PV-S, PV-I and PV-T decreased with increasing moisture content. Tg increased with the addition of saccharides. The state diagram yielded maximallyfreezeconcentrated solutes at 73.2%, 73.4%, 72.6% and 73.4% solids with the characteristic temperature of glass transition being -71.35℃, -64.76℃, -58.36℃ and -59.36℃ for PV, PV-S, PV-I and PV-T, respectively. The corresponding unfreezable waters for PV, PV-S, PV-I and PV-T were 26.8%, 26.6%, 27.4% and 26.6%, respectively. The storage stability and shelf life of meat can be markedly improved by addition of saccharides especially inulin and trehalose.
