Chapter 9 - Solar applications for drying of agricultural and marine products

Abstract

Food drying has been an ancient and low-cost technique of preserving food for a long time. Since solar energy is abundant and free, adopting solar drying technology can be the best solution for drying agricultural and marine products in which the moisture content of products is reduced, assisting in their long-term preservation. There are several solar drying methods including direct, indirect, and mixed-mode. In the direct method, food products are placed in direct exposure to sunlight for drying due to which color, aroma, and nutrients of the dried product may be affected after drying, while in the indirect method, generally, solar energy is used to produce warm air which is used for drying food products. Additionally, in the mixed method, a combination of direct and indirect methods is utilized for drying. In recent years, several technical advancements in the field of drying agricultural and marine products have been made, resulting in more efficient energy use and the production of high-quality final dried products. In this chapter, the principle, technical advancements, and economy of various solar drying methods to dry agricultural and marine products are presented and discussed and some commercial solar drying projects are introduced. In the end, the main barriers and prospects of solar drying technology are explored.