Influence of the dehydration method on the quality of round summer squash snacks [Cucurbita maxima var. Zapallito (Carr.) Millán)]

Abstract

The growing interest in snacks of non-starchy vegetables, prepared without frying is explained by its lower caloric density, compared to dehydrated and fried potatoes. Occasionally, conventional high-temperature drying methods may cause losses of bioactive components. Consequently, there is interest in the search for new processing methods that reduce such losses. In this work, the quality of round summer squash snacks (phenolic antioxidants, carotenoids, sugars, acidity, color, sensory acceptability and hygroscopicity) obtained by two different methods was evaluated: 1) hot air drying (SAC) or 2) by combined method of osmotic dehydration (DO) with NaCl followed by a hot air drying stage (DO + SAC). Depending on the concentration of NaCl used, the DO stage allowed to reduce the initial humidity of this vegetables by 15-30%. The incorporation of a DO pre-treatment before hot air drying did not affect product acidity, sugars and phenolic compounds. The snacks obtained by the combined DO + SAC method, showed better color and sensory acceptability, higher level of extractable carotenoids and lower hygroscopicity than those produced by SAC. Results show that combining osmotic dehydration with hot drying, improve the physical, nutritional and sensory properties of vegetable snacks.