Amount and Size of Ice Crystals in Frozen Samples as Influenced by Hydrocolloids

Measurement of the heat of fusion of frozen hydrocolloid-water solutions and of ice cream mix by differential scanning calorimetry indicated that hydrocolloids, when incorporated at a concentration of 2% (wt/wt) or less, cause only a small reduction (usually less than 3%) in the amount of ice formed. Based on the microscopic appearance of the ice cream mix, with and without gelatin, it was concluded that gelatin at a concentration of .28% (wt/wt) does not have a significant effect on: 1) the amount of ice that forms in ice cream mix, 2) the size and shape of the ice crystals existing soon after freezing, or 3) the rate at which recrystallization of ice occurs during a 2-wk period at −15 ± 2°C. It would appear likely that gelatin exerts a desirable influence on the sensory texture of frozen desserts by some mechanism other than control of ice crystal size or altering the amount of ice formed.