Advances in intermittent batch drying of foods

Longer time consumption, lower energy efficiency and poor quality attributes are associated with convective drying. To overcome these traditional problem of convective drying, intermittent drying is the best option. The main advantages of intermmitent drying include enhanced diffusion of heat and mass transfer, development of internal moisture gradients which enhance the drying rates without increasing surface temperatures. The aim of this chapter is to highlight the recent advances of intermittent drying techniques, discuss its advantages and disadvantages, and explore the applicability of intermittent drying techniques in drying of different types of materials. The performance of the intermittent drying systems, in terms of drying effeciency, energy consumption and food quality is evaluated and compared to conventional drying method. The different popular intermittent drying methods including intermittent convective, variation of energy source, superheated steam and fluidized bed drying are discussed in detail, and their effects on energy effeciency and food quality parameters ares also presented