crystallizes, enzymes and other reactive molecules become unusually concentrated and react abnormally The other damage is physical disruption caused by the water crystals, whose edges puncture cell walls and membranes When the food is thawed, the cell fluids leak out of the cells, and the food loses crispness and becomes limp and wet Producers of frozen foods minimize the size of the ice crystals, and so the amount of damage done, by freezing the food as quickly as possible to as low a temperature as possible, often –40ºF/–40ºC Under these conditions, many small ice crystals form; at higher temperatures fewer and larger crystals form, and do more damage Home and restaurant freezers are warmer than commercial freezers and their temperatures fluctuate, so during storage some water melts and refreezes into larger crystals, and the food’s texture suffers Although freezing temperatures generally reduce enzymatic and other chemical activity, some reactions are actually enhanced by the concentrating effects of ice formation, including enzymatic breakdown of vitamins and pigments The solution to this problem is blanching In this process the food is immersed in rapidly boiling water for a minute or two, just enough time to inactivate the enzymes, and then just as rapidly immersed in cold water to stop further cooking and softening of the cell walls If vegetables are to be frozen for more than a few days, they should be blanched first Fruits are less commonly blanched because their cooked flavor and texture are less appealing Enzymatic browning in frozen fruit can be prevented by packing it in a sugar syrup supplemented with ascorbic acid (between ẳ and ắ teaspoon per quart, 7502,250 mg per liter, depending on the fruits susceptibility to browning) Sugar syrup (usually around 40%, or 1.5 lb sugar per quart water, 680 gm per ...reduce enzymatic and other chemical activity, some reactions are actually enhanced by the concentrating effects of ice formation, including enzymatic breakdown of vitamins and pigments The solution to this problem is... In this process the food is immersed in rapidly boiling water for a minute or two, just enough time to inactivate the enzymes, and then just as rapidly immersed in cold water to stop further cooking and softening of the cell walls... cooking and softening of the cell walls If vegetables are to be frozen for more than a few days, they should be blanched first Fruits are less commonly blanched because their cooked flavor and texture are less appealing