Freezing behavior of water as influenced by ice cream stabilizers.

摘要

The milk cryoscope has been successfully adapted for study of the freezing behavior of solutions and for distinguishing the abilities of stabilizers in delaying ice crystal growth. The hypothesized mechanism of stabilizers preventing heat shock by acting as ice crystal nucleaters is rejected. The high viscosity caused by stabilizers resulting in the suppressed convection rate of the model ice cream solution. The amount of freezable water as influenced by ice cream stabilizers in both water and model ice cream systems is determined by DSC. The stabilizer is shown to have a significant effect in binding water, which makes water unavailable for freezing. Diffusion is postulated as an important kinetic property in controlling ice crystal growth. Carboxymethylcellulose (CMC) is examined to have greater effect than sucrose in controlling diffusion of water molecules in the solution.; The main mechanisms of ice cream stabilizers on preventing heat shock investigated in this study are water binding and diffusion control. Among the three stabilizers, guar gum, locust bean gum and CMC, evaluated in this study, guar gum is the most effective one in delaying ice crystal propagation and water binding. These mechanisms can be applied in more efficient formulation of stabilizers mix for better heat shock prevention of ice cream.