Quality properties of fruits as affected by drying operation

ABSTRACT

The increasing consumption of dried fruits requires further attention on the quality parameters. Drying has become necessary because most fruits are highly perishable owing to their high moisture content and the need to make them available all year round and at locations where they are not produced. In addition to preservation, the reduced weight and bulk of dehydrated products decreases packaging, handling and transportation costs. Quality changes associated with drying of fruit products include physical, sensory, nutritional, and microbiological. Drying gives rise to low or moderate glycemic index (GI) products with high calorie, vitamin and mineral contents. This review examines the nutritional benefits of dried fruits, protective compounds present in dried fruits, GI, overview of some fruit drying methods and effects of drying operations on the quality properties such as shrinkage, porosity, texture, color, rehydration, effective moisture diffusivity, nutritional, sensory, microbiological and shelf stability of fruits.

KEYWORDS:

• Thermal processing
• shrinkage
• porosity
• rehydration
• nutrients
• sensory properties
• pretreatment
• dried fruits

Funding

We want to acknowledge the financial support from the research fund and the work study programme of the University of Venda, Thohoyandou, South Africa.