Modelling water absorption of pasta during soaking

Rehydration of pasta at 20, 40, 60 and 80 °C was examined using Fick’s Second Law of Diffusion to describe the rehydration kinetics. The process was characterized by two effective diffusion coefficients ( D 1, D 2). The effect of temperature on D was interpreted using the Arrhenius relationship. Application of the Peleg and Weibull models were investigated for predicting water absorption of penne pasta. It was shown that the Peleg constants k 1 and k 2 decreased with temperature. The Weibull parameter, α, was constant with temperature, while the kinetic parameter, β, decreased with increasing temperature (40–80 °C). On rehydration, dry pasta changed from a homogeneous, porous structure with few visible starch granules, to a porous structure containing swollen starch granules held within a protein matrix. At an elevated temperature (80 °C), the structure then developed into an open network of coagulated protein. Sample diameter increased on rehydration, with the magnitude of the volume increase increasing with temperature and time.