A Semi-Empirical Model for Mass Transfer in Carbohydrate Polymers: A Case of Native Cassava Starch Hydration Kinetic in Hot Water Media

Despite several works in the literature that approach modifications of starch to obtain hydrophobic characteristics, few studies have the objective of understanding and modeling the mechanisms of water absorption in starch. This paper aims to determine the parameters of a model based on mass balance to represent the process of native cassava starch hydration. For that purpose, experimental data on the hydration of natural starch subject to different temperatures are collected. Next, a semi-empirical model obtained by the differential balance of the amount of hot water in the sample is adjusted for each temperature, and model parameters are studied. Results reveal that the mass transfer constant of the model does not suffer from a significant influence of temperature on hydration. However, the equilibrium moisture content is affected by this temperature. Through this study, it is concluded that: i) the hydration of natural starch profile has a logarithmic behavior over time, and ii) the correlation that best describes the behavior of equilibrium moisture content is linear. Results allow the construction of a generalized model for the range of studied temperatures. Finally, it is suggested the replication of the methodology applied in this paper to analyze other starch modifications.