Equilibrium water and salt contents of sardine sheets during osmotic dehydration

Our objectives were to experimentally determine the equilibrium water and salt contents and compare the performance of prediction according to the models of Zugarramurdi and Lupin, and Azuara et al. for osmotic dehydration of sardine sheets using brine at different concentrations (0.15-0.27 g NaCl/g) and temperatures (32-38 degrees C). The high regression coefficients (R-2 > 0.92) indicated the acceptability of both models for determining the equilibrium contents. The coefficients of determination and the modulus of mean relative errors for both models indicated that Zugarramurdi and Lupin model could be advantageous in estimating the equilibrium water and salt contents. Multiple comparison of means showed that equilibrium water and salt contents predicted by the model of Zugarramurdi and Lupin were lower than those by the Azuara et al. model, at all concentration and temperature conditions. The values differed by 9.4-46.9% for equilibrium water content and by 3.5-44.1% for equilibrium salt content. (C) 2005 Published by Elsevier Ltd. on behalf of Swiss Society of Food Science and Technology.