The Use of a Hybrid Drying Method with Pre-Osmotic Treatment in Strawberry Bio-Snack Technology

Abstract

AbstractThe aim of this study was to determine the effect of osmotic pre-treatment on physical and sensory properties of dried strawberry. Frozen strawberries were dehydrated in sucrose solution with/without 5 or 15 % concentrated chokeberry juice. Then, samples were dried in hybrid (convective-microwave-vacuum) and freeze-drying method. The chokeberry juice concentrate addition to the osmotic solutions had no effect on the mass transfer of dehydrated strawberries but changes in sensory properties, also after storage. Initial osmotic treatment in sucrose solution with 5 % of chokeberry juice concentrate resulted in improved colour, when 15 % addition caused the darkening of the dried strawberries. Strawberries dried by hybrid method exhibited greater hardness and brittleness than by freeze-drying, which were slightly higher evaluated in the sensory analysis. Storage for 3 months resulted in an increase in the hardness of the samples, the reduction of colour parameters and sensory quality.