Study of the rehydration kinetics of nixtamalized corn by using two nixtamalization methods

The present work aimed to study the rehydration kinetics of previously nixtamalized and dried corn. Nixtamalization was carried out by two methods: using wood ash (classical method) and using calcium hydroxide (Ca(OH)2) (traditional method), after the samples were sun-dried. The rehydration kinetics was described using six mathematical models (Fick, Peleg, Weibull, Page, Ibarz et al. and first-order model) in which the possible interpretation of its parameters and the goodness of fit was evaluated. As results, it was obtained that the nixtamalization with wood ash obtained better rehydration properties. The kinetic parameters values of all the used models showed that the rehydration in this treatment was the fastest. In addition, this treatment also reached a high moisture content (49.22 ± 2.10% w.b.) compared to other treatments (Control and Ca(OH)2). The evaluation of the models fit suggests that the first-order model is not adequate to describe the rehydration in any treatment here evaluated, while Fick is suitable to describe the rehydration of Control samples (without treatment), and the models such as Page, Peleg or Weibull are suitable for describing rehydration in samples processed by nixtamalization, especially with ash.