Evaluation of drying methods on osmotically dehydrated cranberries.

摘要

Since cranberry skin is thick and has low porosity, skin pretreatments were considered before drying in order to facilitate water diffusion. Mechanical and chemical pretreatments were considered, by cutting the fruits in half, by making pin holes in each cranberry, and by dipping the fruits in an alkaline solution.;A second pretreatment seemed necessary when drying cranberries in order to reduce their tartness. Cranberries were osmotically dehydrated, by immersing them in osmotic solutions of sucrose or high fructose corn syrup.;Once the pretreatment conditions were selected, four drying methods were tested on the pretreated cranberries. These methods included hot air drying, freeze-drying, vacuum drying and a combination of hot air and microwaves. A quality evaluation of the dried samples was also performed, including evaluation of overall appearance, taste, color, water activity, rehydration capacity and texture. (Abstract shortened by UMI.).