Optimization of Osmotic Dehydration Coupled to Hot Air Drying for the Production of Tomato Powder and Reconstituted Concentrates

Abstract

The brine temperature (X1), the NaCl concentration (X2), the drying temperature (X3), and the drying time (X4) were the 4 parameters explored in this study, which aimed to model the OD-Drying coupling of fresh tomato. A 4 factors Box-Behnken experimental design associated to the response surface methodology (RSM). A transformation of the usual quadratic model was necessary to fit the experimental results. From the obtained models, relationships between the studied factors and the followed responses were establish. From the multicriteria optimization, the following conditions were found as optimal: X1 = 65 ℃, X2 = 5%, X3 = 43.88 ℃ and X4 = 24h. The tomato powder obtained by reproduction of optimal conditions showed better properties than the tomato powder produced by local farmer by sun drying, but similar characteristics as the concentrate prepared from it. From the fresh tomato to the tomato powder obtain using the optimal conditions, the overall quality lost is relatively low.