Rehydration behaviours of five freeze-dried fruits, namely, pineapple, mango, guava, acerola and papaya were investigated and related to the structural changes during drying and glass transition temperature. After freeze-drying performed under vacuum conditions (13 kPa) and initial sample temperature near to 30 C, fruits were allowed to rehydrate at 25 C in distilled water for 6 hr. The Exponential, Peleg and Weibull equations were applied to fit the experimental data using non-linear regression analysis. The statistical criteria used to evaluate the goodness of fit of each equation were the coefficient of determination(R2), the standard error of estimate (SEE) and the mean relative percentage deviation modulus(MRD). The Weibull equation was found to be the most adequate for describing the rehydration kinetics, since it gave the higher R2 values and lower SEE and MRD values for all fruits examined in this study.From indices that take into account the quantity of water absorbed and the losses of solutes, it was
possible to fully characterize the rehydration process of the freeze-dried fruits. Their water uptake
capacity was affected not only by injuries during moisture removal but also by structural collapse
induced by the rehydration process itself, which was explained using the glass transition concept.