Effects of moisture content, molecular weight, and crystallinity on the glass transition temperature of inulin

Effects of moisture content molecular weight (MW) and crystallinity on the glass transition temperature (T-g) and freeze-concentrated glass-like transition temperature (T'(g)) of a fructan (inulin) were investigated using differential scanning calonmetry The T-g of inulin samples decreased with increasing moisture content The T-g of semi-crystal inulin was higher than that of amorphous inulin These results were fitted to the Gordon-Taylor equation and k values reflecting the sensitivity to the water plasticizing effect were obtained The k value was plotted against anhydrous T-g and the relationship of amorphous inulin was described with a linear function T-g of anhydrous inulin samples and T'(g) of inulin-water mixtures Increased with increasing MW and the results were described empirically by a stretched exponential equation These results will help to predict T-g and T-g of mulin depending on the moisture content MW and crystallinity (C) 2010 Elsevier Ltd All rights reserved