Effect of pretreatments on drying of red dacca in a single slope solar dryer

Abstract

AbstractPretreatment of fruits normally increases moisture loss and reduces the overall drying period. The combination of pretreatments and drying assures the least color difference, excellent preservation, and better antioxidant activity. Pretreatment of Red Dacca is soaked in four different solutions, namely honey, lemon juice, sugar syrup, and ascorbic acid, for 10 min. The best solution for pretreatment is investigated among the selected samples. The results indicated that dipping the red dacca in ascorbic acid and lemon juice had a higher impact on moisture loss. The moisture content of the red dacca control samples reduced from 74 to 14% on a wet basis within 8 hr, whereas pretreated red dacca reaches an equilibrium moisture content of 14% within 6 hr. The ascorbic acid dipped samples have shown the best drying rate. The lemon juice samples have the best sensory appeal, whereas honey samples have the best taste over the other samples. The effect of pretreatment on drying characteristics is experimentally investigated on a single slope dryer in both natural and forced convection mode. Pretreated red daca drying is investigated for the first time and the enhancement in performance is compared with three kinds of drying modes.Practical applicationsDue to a lack of processing facilities, the farmers have to sell their products at very low prices. Red dacca is a popularly consumed fruit and it contains various nutritional and health benefits to humans. The drying process is playing an important role in heat‐sensitive product dehydration. Solar drying is a better choice to reduce the loss and produce good quality red dacca after harvesting. In this research, the best drying and pretreatment method for red dacca is identified from existing literature. The finding obtained from this research work will help to increase the shelf life of food samples by reducing the overall drying time without altering the dryer design.