GIRS 2021
Assessment of Physicochemical Properties of Cacao Powders by Inverse Gas Chromatography and Dynamic Vapor Sorption


The characterization of cacao is challenging due to its multi-component structure. Cacao powders contains a mixture of crystalline and amorphous components. Measuring the glass transition temperature by differential scanning calorimetry is rather difficult. In addition, environmental conditions of temperature and humidity are known to affect particle properties at the surface. Interactions at the surface are the first ones to respond to external variables. Thus, water sorption and diffusion are important to understand and control for a desirable performance. In this study, cacao particles with various lipid content at the surface were studied in order to assess the physicochemical properties by inverse gas chromatography (iGC) and dynamic vapor sorption (DVS) at different temperature and relative humidity conditions. Diffusion coefficient, partial molar enthalpy of sorption, lipid phase surface transition, Arrhenius activation energy of diffusion, and surface energetics parameters were obtained by surface characterization methods. The evaluated properties can be related to predict stability and performance base in thermodynamic parameters for cacao processing and formulations considerations.