Drying kinetics and selected physico - chemical properties of fresh cranberries preserved with microwave – vacuum process

Abstract

A one stage drying process for dried cranberry production, employing a vacuum microwave technique, is proposed. The process consists of a specific sequence of microwave energy dosage at a given vacuum level. During the 60 minute process, three sub-stages can be identified: osmotic dehydration, intensive water evaporation and stabilization. Mass transfer, as well as quality changes during the process, has been described, and the final product quality compared to purchased control. The proposed method of dried cranberry production resulted in a microbiologically stable product  (aw=0.62) of a decent sensory quality, with an antioxidant potential three times higher than traditional products. Keywords: Vaccinium macrocarpon; microwave-vacuum drying; ready-to-eat snack