ABSTRACT
This chapter discusses the effectiveness of vacuum impregnation (VI) in modifying composition and structure of porous fruits with different kinds of solutes, combined with water removal as well as their influence on some physical and structural properties. It analyses the possibility to enhance product stability during freezing-thawing processes on the basis of the changes promoted in the water behavior in non-equilibrium state at subzero temperatures. VI technique can offer interesting prospects in developing pre-treatments to modify the initial composition of porous fruits, introducing cryoprotectant solutes and making them more suitable for resisting damages caused by the frozen-thawing processes. The key to cryoprotection lies in controlling the physical state of the freezeconcentrated amorphous matrix surrounding the ice crystals in a frozen system, where deteriorative reactions mainly occur. If the impregnation solution is hypertonic, cryostabilization is obtained by using the combination of vacuum impregnation and osmotic dehydration.
