This proposal outlines a study to determine the sorption isotherms of star fruit (Averrhoa carambola) and African star apple (Chrysophyllum albidum) at various temperatures between 30°C and 60°C. The objectives are to determine physicochemical properties, measure sorption isotherms, evaluate commonly used sorption models, and develop empirical models. Understanding the sorption behavior could help reduce loss and waste during transportation by informing proper packaging and storage conditions. Materials, methods, and models to be used are described for measuring moisture content, proteins, fats, ash, carbohydrates, and creating water activities to plot the sorption isotherms.