Modeling mass transfer in brine salting of chickpea

Abstract

Salted chickpea (Cicer arietinum L.) is increasingly used in snack production and in home cooking by soaking in brines. Order to achieve better quality and higher nutrient content, it is important to model and understand the mass transfer processes during this operation. In this work, brine salting of chickpea was studied at 1, 5 and 20% salt concentrations, at temperatures of 25, 50, 75 and 100 °C. Water uptake, salt uptake and non-ash solids loss over time were modeled using the Peleg, Fickian diffusion and anomalous diffusion models. Salt content of brines significantly affects the changes occurring during chickpea soaking. At 1% salt content, the volume gain is larger than when soaking in water, while at 5 and 20% swelling decreases, with a lower solids’ loss. The fit of each model to experimental data was assessed using the Coefficient of Determination, the Root Mean Square Error, the Akaike Information Criterion, and the errors of the fitted parameters of each model. The results show that the Fick model is at least as good as the Peleg model in predicting the mass transfer of each considered component, but the influence of the equilibrium parameter is more clear on the Peleg model, resulting in better forecasts of the kinetic parameter. The anomalous diffusion model was not adequate to fit neither the water, the salt nor the solids loss, resulting in large errors in both the diffusion coefficient and the equilibrium parameter.