Moisture adsorption is considered a critical factor during production and shelf-life of puffed corn cakes (PCC). This study aims to develop and validate an instrumental method and a mathematical model for the characterization of the textural modifications caused by the moisture adsorption in PCC. For that purpose, PCC were stored at different relative humidities to achieve a wide range of water activities (from 0.1 to 0.8 at 22 ± 1 °C). A flexion-compression test was successfully validated in order to characterize the average textural properties of a PCC batch. A mathematical model considering consecutive elastic and plastic zones satisfactorily fitted (average VAR 99.65% and MRE 3.29%) the average stress-strain profiles of PCC and reported useful textural parameters, such as the deformability modulus (E), critical strain (εc), and n curvature parameter. The structural modifications caused by moisture adsorption led to the reduction in E and n and the increase in εc. Even minor changes on the PCC moisture content involve remarkable modifications of the textural properties, which has to be considered for industry and retail distribution.
Keywords: flexion–compression test; modelling; moisture adsorption; puffed corn cake; texture; water activity.