Why do food manufacturers recommend that frozen food should not be refrozen ?
Refreezing is bad for three reasons. First, by refreezing food you multiply the damage to it–any cells that escaped rupture the first time the food was frozen are at risk of being ruptured the second time. Second, when food has been frozen and thawed out, it has larger pockets of liquid within it than the first time due to the ruptured cells. When the food is refrozen, the larger pockets of liquid can freeze into much larger ice crystals, which can lead to more damage to the food. Manufacturers use flash-freezing, which produces smaller ice crystals, minimal cell damage. Third, and most important reason not to refreeze is the increased risk of spoilage due to micro organisms growing.
