Recent efforts in developing agricultural product drying processes using solar energy

Dried foods, especially fruits, have become a requirement of many fields in most societies not limited only to developing countries that often preserve food for periods of drought. Consequently, there has become a development in the concept of dried foods for many people, and this is reflected in the methods of producing and drying fruits, in particular, there is rapid development in the methods of production and manufacturing, it has recently become a prevailing trend in the whole world on the necessity of limiting and saving in non-renewable energy. The current work presents and discusses some efforts in developing agricultural product drying processes. Solar drying and other methods, spray drying, freeze-drying, Refractance Window, and microwave drying, as well as several pre-treatment techniques, were assessed in terms of performance, product quality, and economic feasibility. Furthermore, the solar drying methods have been classified based on the solar dryer type into, absorber plate solar collector-based dryers, tube solar collector heater-based dryers, and solar dryers with thermal storage. Accordingly, a CO₂ reduction of 135.04 tons was indicated by utilizing an evacuated tube solar heater for drying ginger.