Some physical properties and adsorption isotherms of vacuum-dried honey powder with different carrier materials

Abstract

This study was aimed at determining effects of different carrier materials and temperatures on water adsorption properties and net isosteric heat of vacuum-dried honey powders. The particle size and Carr index of samples were between 100.04 and 169.29 mu m. and 23.03-26.59%, respectively. The adsorption isotherms of samples were type II and the Caurie and Peleg models were found to be best for evaluating the adsorption properties of samples. The mean X-0 values and adsorption surface areas of samples with maltodextrin, gum Arabic and whey protein isolate were 4.43, 4.76 and 4.22 g/100 g dry matter and 74.89, 65.51 and 68.76 m(2)/g, respectively. Increasing the temperature decreased the number of adsorbed layers and adsorption surface area of samples. Additionally, the net isosteric heat of samples decreased from 10.09 to -0.78, 20.02 to -0.53 and 7.30 to 0.04 kJ/mol when the moisture content increased by 3-50 g/100 g dry matter in samples with maltodextrin, gum Arabic and whey protein isolate, respectively.