Results and discussion
3.1 Process variables modulation
Freshly cut apples were treated by VI with different pressures (from 857 to 50 mbar) at constant time (10 s) by using water as impregnating agent; the mass transfer parameters, expressed by total mass change (ΔM0t), water mass change (ΔMwt) and soluble solids change (ΔMsst) are reported in Table 1.
Table 1. Mass transfer parameters, soluble solids (°Brix) and pH of apples vacuum impregnated at different pressure and time values.