Effects of maltodextrin and pulp on the water sorption, glass transition, and caking properties of freeze-dried mango powder

Effect of maltodextrin on the water sorption behavior and glass transition temperature (T-g) of freeze-dried mango solute (water-soluble mango material) was investigated. In addition, the caking property of freeze-dried mango puree and mango solute with and without maltodextrin was investigated. The T-g of mango solute (32 degrees C) increased discontinuously with maltodextrin weight fraction with a step-point between 0.6 and 0.7. The pulp of mango decreased the hygroscopicity and increased the T-g of mango powder to 49 degrees C. The degree of caking was reduced by the additions of maltodextrin and pulp because of the increased T-g. The powder samples except for maltodextrin showed a small degree of caking (below 13%) even below their T-g. An empirical model to predict the effect of water content on T-g was applied to the mango solute-maltodextrin mixtures. The predicted T-g values were in good agreement with the measured values (coefficient of determination = 0.919).