Emerging Technologies for Food Processing, 2nd Edition

11.3. Effect of Process Parameters on Mass Transfer and Structure

The rate of dehydration also increases with an increase in both the concentration and temperature of the osmotic solution. Agitation is indeed one of the key factors, and an adequate level of agitation ensures reduction or elimination of liquid-side mass transfer resistance and provides a constant driving force.

At low solid-to-solution ratios, as dehydration progresses the osmotic solution becomes increasingly dilute, and the driving force for further release of water decreases. It is necessary to have a solid-to-solution mass ratio of around 1:20 in order to ensure a more or less uniform driving force. It is reported that an increase in fruit-to-sugar syrup ratio (from 1:1 to 1:4.5) ...