Ice crystals are comparatively unstable, and during frozen storage, they undergo changes in number, size, and shape, called collectively as recrystallization. This is probably the most important reaction leading to eminence losses in all frozen foods. Some recrystallization happens sensibly at constant temperatures, but by far the majority of problems are created as a result of temperature fluctuations. If the temperature during the frozen storage of ice cream increases, some of the ice crystals, mainly the smaller ones, melt and consequently the amount of unfrozen water in the serum phase increases. Conversely, as temperatures decrease, water will refreeze but does not renucleate. Rather, it is deposited on the surface of larger crystals, so the net result is that the total number of crystals diminishes and the mean crystal size increases. Temperature fluctuations are common in frozen storage as a consequence of the cyclic nature of refrigeration systems and the need for automatic defrosts. However, mishandling of product is probably the biggest culprit. The sight of ice cream sitting unrefrigerated on a loading dock, in the superstore aisle, in a shopping cart, or in someone's grocery bag is too general. If one were to track the temperature history of ice cream throughout distribution, retailing, and lastly consumption, one would find a great number of temperature fluctuations. Each time the temperature changes, the ice to serum content changes, and the minor ice crystals disappear while the larger ones grow even larger. Recrystallization is reduced by maintaining low and stable storage temperatures.