10 - Infrared drying

Abstract

Drying is one of the oldest preservation methods used to protect food from spoilage. It is primarily aimed at removing water from food products. Drying provides several advantages, including enhanced shelf life, reduction in weight, volume, and space for storage, and easier manipulation of the products, thereby decreasing transportation costs. The selection of a suitable drying method is very important for final product quality and operation cost. The conventionally used hot air drying is timeconsuming and also does not guarantee a high-quality product and has low energy efficiency. Several new drying methods, including microwave, fluidized bed, spouted bed, infrared (IR), solar, simple convective and desiccant, heat pump, freeze, osmotic, vacuum, pulsed electric field, high hydrostatic pressure, and IR drying, were developed. IR drying has several advantages over conventional drying and has been increasingly used in drying food products. This chapter briefly describes the principle of IR heating mechanism, heat and mass transfer in IR heating, application of IR drying in drying of cereals, fruits, vegetables, and nuts, commercial scale IR dryers, and also provides recommendations for future research needs in the field of IR drying of food crops.