Experimental study on drying kinetics of ivy gourd using solar dryer

摘要

Vegetable preservation through drying technology is an effective method to minimize wastage while satisfying the essential nutrition requirements. It is necessary to expand the existing technologies to preserve seasonal and regional specific vegetables. The present study is intended to find suitable conditions to increase preservation capacity through solar drying. A single slope solar dryer (SSSD) is designed, fabricated and ivy gourd is taken as a vegetable sample. Experiments are carried out in the highest temperature region in South India at 10.925 degrees N latitude, 79.838 degrees E longitude. The safe moisture content of the passive and active mode solar dryer was attained in 9 and 7 hr whereas it took 11 hr in sun drying. During the dehydrating process, the temperature of the system varied from 35 to 71 degrees C. Existing kinetics models are used to optimize the "goodness of fit" and proposed a novel model to suit India's environmental conditions. Exergy analysis and thin layer drying kinetic studies are performed and studied the influence of various parameters in the dehydrating of ivy gourd. The study revealed that the air temperature, RH, global radiation, and airspeed, significantly influence the drying kinetics. However, all the above four drying parameters are interconnected to enhance the drying process and which in turn enhance the drying kinetics process. Obtained results are explained with suitable discussions.Practical Application Almost 40-50% amount of food items annually are rotten all over the global due to deficiency of proper preservation methods. Solar drying is found as a sustainable approach for food preservation; however, the food items dehydrated under sun dehydrating lose their nutritional, medicinal properties due to slow and nonuniform dehydrating rate. In this article, the newly designed SSSD is developed and a thin-layer dehydrating mathematical correlation for freshly harvested ivy gourd is conducted. The results showed that forced convection solar drying setup could enhance the product quality of ivy gourd and also decrease the dehydrating time.