| The objective of this work was to determine the most appropriated chemical treatment to be used to dry grapes cv. Rubi for raisin production. Drying curves for convective drying with air at 50ºC, in a tray drier, were obtained for grapes submitted to chemical pretreatments with different concentrations of potassium carbonate and olive oil, and different dipping times, according to factorial designs. Convective drying curves were also obtained for grapes pretreated in aqueous suspensions of soybean lecithin, at varied lecithin concentrations and dipping times. Page model was adjusted to the experimental drying curves, and the calculated drying times showed that the best pretreatment consisted in dipping grapes for 2 minutes in a 5% olive oil and 6% K2CO3... |
