Stability of Fructooligosaccharides in Convectively Dried Fruits After Initial Osmoconcentration

Abstract

The aim of this study was to determine the effect of temperature and time of convective drying on the content of fructooligosaccharides (FOS) in apples, plums and strawberries to which FOS had been introduced by osmoconcentration. The share of oligosaccharides in total sugars was analyzed. In apple tissue, fructooligosaccharides were stable in the temperature range 40–80 °C during drying for up to 8 h. Convective drying of osmotically dehydrated strawberries caused FOS losses; the FOS retention after 8 h at 80 °C was 40%. In the case of plums, 40% retention was recorded after just two hours at 80 °C. Therefore, in the case of some fruits, obtaining a satisfactory level of fructooligosaccharides in the dried material with the assumed level of dry substance requires the determination of appropriate process parameters.