Recrystallization of ice during bulk storage of ice cream

Ice recrystallization was studied in 1.9 L containers of ice cream stored so that surface temperature of ice cream was controlled with fluctuations of +/-1.0 degrees C. Core and surface samples were taken at regular intervals and analyzed for ice crystal size by cold-stage microscopy and image analysis. Mean ice crystal size plotted vs. time(0.33) resulted in a straight line, with a slope equal to recrystallization rate (mu m day(-0.33)). Storage temperatures between -15 and -5 degrees C were studied. Recrystallization rate increased with storage temperature and extent of temperature fluctuations. Within a single container, mean ice crystal size grew significantly larger in ice cream at the outside wall than near the core of the package. Recrystallization rates determined in this study were compared to those found at identical temperature conditions, but in an accelerated storage study. Recrystallization was more rapid in the accelerated study for fluctuating temperature, but slower for constant temperature. Copyright (C) 1996 Elsevier Science Limited.