Berinjela osmodesidratada para a obtençao de conserva: otimização e cinética de secagem.

Abstract

This work was developed with the objective of processing the eggplant (Solanum melongena L.) using combined techniques of osmotic dehydration and convective drying, aiming at obtaining a new product for the food industry. The "in natura" eggplant slices, dried and dried were characterized as physical-chemical parameters (total soluble solids, ash, total solids, titratable total acidity, pH and sodium), physical (water content, water activity, color and texture) and chemical (minerals). The slices of eggplant "in natura" presented little acid, with the pH much closer to the neutral one compared to the slices of eggplant, the dried and dried, with predominance of the increase in the ash content in the course of the process. The best process condition found for osmotic dehydration of eggplant slices was at the osmotic dehydration temperature 30 ° C; 3% NaCl concentration and immersion time of 120 min. The convective drying was carried out in a tray dryer at temperatures of 50, 60 and 70 ºC, with air velocity of 1.2 m / s. The experimental data obtained in the drying provided the evaluation of the drying curves, which were adjusted according to the models of Page, Henderson and Pabis, Lewis, Midilli and Cavalcanti Mata. The models of Midilli and Cavalcanti Mata were the ones that best fit the drying kinetics of eggplant slices. The microstructures of slices of eggplants without dehydration and also the slices modified and dried at 70 ° C were analyzed by scanning electron microscopy, where it was possible to observe that the combination of processes in the eggplant slices caused a greater destruction of the cellular structures, as well as a greater disorganization of the cells, resulting from the collapse, becoming a typically amorphous product. The sample of preserved eggplant (olive oil, chilli pepper, parsley and rosemary) was more widely accepted for the appearance, aroma, color, flavor and texture of the eggplant preserves samples than the other canned samples.