Determinación del punto óptimo de cosecha de zapallo (Cucurbita maxima) para la elaboración de chips por fritura al vacío

Abstract

The purpose of this research was to determine the optimum harvest stage of squash (Cucurbita maxima) for obtaining chips using vacuum frying technology. The study was carried out on the macre variety, and external maturity indicators were determined for the two harvest stages (100 and 120 days). The hardness of the rind was determined by a penetrometer in N, in the apical, middle and basal zone. In the 120-dayold pumpkin a force of 84.86 N, 64.05 N and 53.65 N was exerted in the 3 zones respectively, while the pumpkin harvested at 100 days showed a lower force of 71.05 N, 64.1 N, 47.6 N. The changein color of the rind is very noticeable at both stages of harvest to determine its coloration, the Munsell chart of plant tissues was used, which showed colors between green to light green (100 days) and green with reddish tones (120 days). The change in color of the peduncle is another external indicator of maturity, because it changes from yellow-green to light yellow tones in the first stage of harvest, while in the second stage of harvest the peduncle shows lighter yellow tones. This process is due to the fact that the peduncle begins to lignify, preventing the passage of sap, turning from greento light yellow, the peduncle becomes corky and loses weight. The 120-day-oldfruit welghs 198g and the 100-day-old fruit 209.33g. The characteristic color of the pumpkin pulp is orange due to the high content of carotenoids and vitamin C, and physicochemical analysis was carried out on the fresh material. For vacuum frying, 3 frying times were established (12, 13 and 15 min), with a temperature of 100%C at a pressure of -0.64 bar and a centrifugation time of 3 min. Physicochemical and sensory analyses of the pumpkin chips were carried out. However, some nutrients were lost in this process. In the 120-day-old pumpkin, 57% protein, 9.09% starch and 73% vitamin C were lost; in relation to fiber, a gain of 10.12% to 25% was obtained. Finally, a sensory test was carried out to determine the best treatment by 10 panelists, using a scale with a 5-point rating. T5 achieved a higher score (120 days, 13 min) retains better organoleptic and nutritional characteristics in terms of protein 3.99%, fiber 27.00%, ash 5.21%, ethereal extract 12.1%, nitrogen free extract 51.70%, total sugars 43.90% and starch 30.66%. Therefore, the application of vacuum frying technology helps to preserve the organoleptic and nutritional characteristics of the chips and contributes to provide benefitsto the consumer by offering healthy products, helping his health, and to the farmer by avoiding post-harvest losses and improving the quality of life. Key words: harvest, maturity, pumpkin, vacuum frying, chips. Finally, a sensory test was carried out to determine the best treatment by 10 panelists, using a scale with a 5-point rating. T5 achieved a higher score (120 days, 13 min) retains better organoleptic and nutritional characteristics in terms of protein 3.99%,fiber 27.00%, ash 5.21%, ethereal extract 12.1%, nitrogen free extract 51.70%, total sugars 43.90% and starch 30.66%. Therefore, the application of vacuum frying technology helps to preserve the organoleptic and nutritional characteristics of the chips and contributes to provide benefits to the consumerby offering healthy products, helping his health, and to the farmer by avoiding post-harvest losses and improving the quality of life