Experimental Analysis and Mathematical Modelling of the Effect of Starch Gelatinization on Chestnuts Rehydration

摘要

The paper presents an experimental and modeling study of the rehydration process ofrnair-dried chestnuts. Sorption curves are obtained for chestnuts dried at 40, 60, and 80 oCrnimmersed in water at 90 oC and differential scanning calorimetry (DSC) measurementsrnare performed to characterize the evolution of the starch gelatinization process on therntransport of water during rehydration. In this way, stages of the rehydration processrngoverned by different physical mechanisms are identified. A large growth in thernabsorption rate is observed at intermediate times due starch gelatinization while slowrnabsorption is found at large times due to the swelling of the sample. A mathematicalrnmodel is therefore presented enabling to describe the effect of diffusion, swelling andrnstarch gelatinization. Parametric estimation of the model parameters is performed byrnnonlinear regression techniques providing indications on how to select processingrnconditions so as to achieve desired characteristics of the final product..