Recent advances in drying and dehydration of fruits and vegetables: a review

J Food Sci Technol (JanuaryFebruary 2010) 47(1):1526 15

J Food Sci Technol (JanuaryFebruary 2010) 47(1):1526

REVIEW ARTICLE

Empowering the Food Professional

Recent advances in drying and dehydration of fruits and vegetables: a review

Sagar V. R. . Suresh Kumar P.

Revised: 2 September 2008 / Accepted: 29 April 2009 Association of Food Scientists and Technologists (India), Mysore

Abstract Fruits and vegetables are dried to enhance storage stability, minimize packaging requirement and reduce transport weight. Preservation of fruits and vegetables through drying based on sun and solar drying techniques which cause poor quality and product contamination. Energy consumption and quality of dried products are critical parameters in the selection of drying process. An optimum drying system for the preparation of quality dehydrated products is cost effective as it shortens the drying time and cause minimum damage to the product. To reduce the energy utilization and operational cost new dimensions came up in drying techniques. Among the technologies osmotic dehydration, vacuum drying, freeze drying, superheated steam drying, heat pump drying and spray drying have great scope for the production of quality dried products and powders.

Keywords Superheated steam drying . Heat pump drying . Fruits and vegetable dehydration . Freeze drying . Spray drying . Pulsed electric eld

Introduction

Fruits and vegetables are important sources of essential dietary nutrients such as vitamins, minerals and bre. Since the moisture content of fresh fruits and vegetables is more than 80%, they are classied as highly perishable commodities (Orsat et al. 2006). Keeping the product fresh is the best way to maintain its nutritional value, but most storage techniques

require low temperatures, which are difcult to maintain throughout the distribution chain. On the other hand, drying is a suitable alternative for post harvest management especially in countries like India where exist poorly established low temperature distribution and handling facilities. It is noted that over 20% of the world perishable crops are dried to increase shelf-life and promote food security (Grabowski et al. 2003). Fruits, vegetables and their products are dried to enhance storage stability, minimise packaging requirements and reduce transport weight. Nonetheless, in India hardly any portion of perishables are dried which leads to enormous loss in terms of money and labour besides steep rise in prices of commodities...