Solar drying of fruits – A comprehensive review

Abstract

Developing an efficient and economic solar dryer for continuous drying of agricultural food products has become potentially a viable substitute for fossil fuel in developing countries like India. Drying is a process of removing moisture content from the most important agricultural products like fruits and vegetables. This process is widely used for preservation and storage of agricultural products. The fruits and vegetables must be maintained at good quality because it has very high nutrition. The best way to maintain its nutritional value is to keep the items as fresh. Multiple methods are available for this preservation, but drying is the most common way of preserving food because the storage life is increased. Solar power is used for drying fish and agricultural products such as cocoa, coffee, rubber, cotton, tobacco, corn, tea. There are various types of solar drying systems were available for agricultural food products. Therefore, in this review paper, an attempt has been made to summarize the previous and current research in the field of solar dryers for drying of agricultural food products. Solar tunnel drier architecture, solar drier testing with drying vegetables, economic analysis and dried crop quality analyzes were discussed. In some cases, the moisture content of these items reaches 90%. The quality of water is considered the main cause for the development of microorganisms contributing to decomposition. The efficiency of a solar dryer with both a natural and a forced convection solar drier for fruit and vegetables were analyzed and compared in this article. Drying rate, weight losses and humidity removal were discussed.