Sorption Isotherms for Triticale Seed

Abstract. Triticale is being evaluated as a substitute for corn in animal feed and as a forage crop for Florida. Storage of triticale seed is difficult in Florida’s hot and humid climate, and more information about the relationships between equilibrium moisture content (EMC) and equilibrium relative humidity (ERH) at constant temperature (sorption isotherms) of triticale is needed to develop improved storage methods. Therefore, the primary research objective was to measure the EMC for triticale seed at different ERH values at three different constant temperatures (5°C, 23°C, and 35°C) using six desiccation jars containing different saturated salt concentrations. The secondary objective was to determine the best fit equation describing these relationships. The six saturated salt solutions provided relative humidity (RH) values of 11%, 23%, 33%, 58%, 75%, and 84% at 25°C. An average of ten weeks was required to reach equilibrium when the initial moisture content (MC) of the seed was 13.35% (wet basis). The results of this experiment were used to develop three prediction equations, (modified Henderson, modified Chung-Pfost, and modified Oswin equations) representing the relationship between ERH and EMC. The results show that the modified Chung-Pfost equation represented this relationship most accurately, with a standard error of 2.4% and a coefficient of determination obtained from the scatter plot for the predicted vs. measured RH (R²) equal to 0.99. Overall, this result will aid the development and improvement of drying and storage methods for triticale seed.