Recent Advances in Dehydration of Fruits and Vegetables

Drying is the oldest method of food preservation.

- Arshi Siddiqui and Khan Chand

INTRODUCTION

Fruits and vegetables have essential dietary nutrients such as vitamins, minerals and dietary fibers which are considered important for a balanced diet. These nutrients reduce the risk of possible deficiencies and help to maintain a healthy lifestyle. Fruits and vegetables have a high moisture content of more than 80%. These are classified as highly perishable commodities and are more prone to spoilage. Drying is a suitable alternative to preserve food in a stable and safe condition by reducing water activity, extending the shelflife much longer than that of fresh produce. Due to the perishable nature of fruits and vegetables, it is necessary to preserve them and drying is one such method for post-harvest management especially in developing countries like India where cold storage facilities are poorly established. Dried foods are tasty, nutritious, lightweight, easy to prepare, easy to store and use.

Since prehistoric times the preservation of fruits and vegetables is done by the sun and solar drying techniques. But due to the poor quality and product contamination, the alternate drying technologies are developed. The most applicable method of drying includes freeze, vacuum, osmotic, microwave, infrared and hybrid drying.

MODERN DRYING TECHNIQUES

Osmotic drying