REVIEW OF OSMOTIC DEHYDRATION OF FRUITS AND VEGETABLES FROM THE PERSPECTIVE OF ITS POTENTIAL APPLICATION IN FOOD PROCESSING IN NIGERIA

Traditional sun and hot air drying appear to be the major preservation methods employed in Nigeria owing to poor energy system and slow advancement in technological development. Excessive dependence of traditional sun drying on climatic conditions has made the method inadequate as an effective response to recurrent post-harvest losses encountered yearly in the country. Besides, evidence abounds to the effect that conventional drying of fruits and vegetables affects their physical and biochemical status leading to shrinkage and alterations in nutritional and organoleptic properties. The relationship between consumption of fruits, vegetables and health necessitated the need for particular attention not only to be focused on their nutritional composition but also on the continual  development of technological processes that are more effective for preserving these products in a form most acceptable to consumers. Osmotic dehydration is a process which partially removes water from cellular materials. This method has recently been receiving increased attention as a potential pretreatment to conventional processes such as terminal drying for quality improvement of fruit products and for energy consumption reduction in such processes. In particular, the effectiveness of the osmotic drying process at ambient temperature may, from the point of view minimizing energy demand, be one of the most powerful indications of its appropriateness in food processing Nigeria. In this paper, the potentials of incorporating osmotic dehydration as a complimentary processing step in the processing of foods in Nigeria are explored