Abstract: Drying is one of the most popular and common fruit preservation technique. Fruits are dried to extend storage life and reduce transport weight. The use of microwaves in drying has been growing in recent years. Now a days microwave drying is the most common method for fruits. In resent research on microwave drying have some limitations like excessive heating at the edges and corners of the product. Due to this scorching problem are occurred also it causes the off-flavor. To reduce the energy wastage and operational cost new dimensions came up in drying techniques. The advantages of MW combination drying techniques include shorter drying times, improved product quality and Flexibility in producing a wide variety of dried products. The drying rate can be significantly increased; the nutritional value, color, and original flavor can be largely maintained; puffing, drying, and sterilization are accomplished simultaneously to enhance the overall product quality; heat loss is decreased because the drying time is shortened and the difference in temperature between the inside and outside of the equipment is small; energy absorption is proportional to the residual moisture content and can be easy controlled; and MW drying can be performed at lower temperatures suitable for processing heat-sensitive materials.

Keywords: Microwave, vacuum Drying, Energy saving, conventional heating.