Crimson Seedless (Vitis vinifera L.) is one of the most important seedless varieties of grape, due to having attractive medium-sized bunches and large, dark-pink berries. It presents excellent sensory characteristics because of its firm, crisp texture, a flavour which varies from sweet to neutral, and uniform colouring. Osmotic dehydration is seen as a good alternative for reducing water activity in this grape, allowing it to be stored for long periods and improving its stability and quality. The objective of this research was to describe the influence of different parameters on the efficient osmotic dehydration of this fruit so as to reduce post-harvest losses and offer new alternatives to the producer. In order to optimize osmotic dehydration, an experiment was conducted in a 2³ factorial design employing the independent variables: temperature (30-50 ºC), time (1-4 hours) and concentration (40-50 ºBrix), with consistant bleaching (30 seconds) and perforation (8 perforations cm-2). The dependent variables used were: ML (Mositure Loss), IS (Incorporation of Solids ) and DEI (Dehydration Efficiency Index). The best conditions for osmotic dehydration, using the DEI as parameter, were the use of bleaching, an osmotic solution of 42 ºBrix, an immersion time of 1.6 hours and a temperature of 46ºC. The response surface models obtained were predictive for ML and IS, but not for IED. The selected product demonstrated the best fit for the Page equation (R² = 0.995).
Dehydration Efficiency Index; Vitis vinifera L.; Dehydration by osmotic solution
