Deshidratación osmótica del zapallo (Cucurbita maxima Duchesne)

Abstract

Pumpkin is a very healthy and nutritious vegetable but its direct consumption as fresh fruit is not very popular, so research in this field has focused in the finding of alternative industrial processing methods more adequate to preserve the natural content of this product. The present work aimed to study the optimal industrialization parameters of pumpkin (Cucurbita maxima Duchesne) submitted to osmotic dehydration. Hipertonic solution was obtained by means of passion fruit juice and honey. This mixture has a high content of carbohydrates, vitamins and minerals. Experimental plot consisted in a two factorial design: honey concentration (30, 40 and 50 ºBrix) and drying temperature (60 and 70 ºC). It were taken into account the following parameters in order to control the process: weight reduction (%) and water loss/solid gain ratio (WL/SG). After osmodehydration, a final air drying step was employed, using a flow rate of 6.75•10-3 m3•s-1. From this step, the effective diffusivity was calculate (m2•s-1). From the sensory point of view, optimal conditions for product development were obtained with the use of a hypertonic solution of 50 ºBrix and a subsequent air drying process at 70 ºC. Final product was rich in carbohydrates and antioxidant capacity, and reached a shelf life of 60 days at room temperature, with a calculated production cost of 0.42 USD per portion 100 g.