Influence of ultrasound and ethanol as a pretreatment on papaya infrared and convective drying characteristics and quality parameters

This study aimed to evaluate the effectiveness of pretreatments on papaya drying behavior and quality parameters. The pretreatment consisted of submerging the samples in ethanol or distilled water for 20 min. The ultrasonic step was conducted in an ultrasonic bath (25 kHz). Samples were dried in an infrared dryer and a convective oven at 60 & DEG;C. The material pretreated with ultrasound and ethanol and submitted to infrared drying presented the shortest drying time (84 min). The two-term exponential model was the most predictive for the drying data fitting. All dried samples showed water activity values below 0.60. Among the pretreatments performed, the use of ultrasound associated with ethanol was more effective in reducing losses of total phenolics, ascorbic acid, and antioxidant activity of dried papaya when compared to the use of water. Infrared drying of the fruit pretreated with the combination of ultrasound and ethanol resulted in no significant difference from the untreated papaya concerning the evaluated quality parameters.Practical applicationsThe consumption of tropical fruits and their derived products has increased in national and international markets, due to the growing recognition of their nutritional properties and subsequent use in the food industry. The presence of nutrients such as bioactive compounds, demonstrates their potential for use in different sectors, increasing the added value of the cultivar. Thus, this study represents a contribution to society, recognizing and valuing the consumption of fruit, contributing to the nutritional conditions of the population, favoring food and nutritional security, and conservation of the species. It also allows, with the use of pretreatments and different types of drying, advances, and information about food preservation methods that have a low environmental impact and the exploration of new forms of fruit consumption, increasing its shelf life and facilitating their transport and marketing.