What Is Freeze Concentration?

At present, the frozen food center temperature is generally around -15 ° C. At this time, most of the water contained in the food is frozen. At this temperature, the percentage of frozen water in food as a percentage of total water is called the freezing rate.

At present, the frozen food center temperature is generally around -15 ° C. At this time, most of the water contained in the food is frozen. At this temperature, the percentage of frozen water in food as a percentage of total water is called the freezing rate.

Freezing rate calculation formula

Freezing rate = (1-food freezing point temperature / food temperature) * 100%

If the freezing point of a food is -1 ° C, and its core temperature is lowered to -5 ° C, at this time, the freezing rate = (1--1 / -5) * 100% = 80%, that is, the food at -5 ° C 80% of the water in it has been frozen ^[1]

As different salts are dissolved in the water contained in food, the more salt there is, the lower the freezing point is. Therefore, when the water in the food juice gradually precipitates and freezes to become ice crystals, the remaining juice has a higher salt concentration and a lower freezing point. The less juice left in the food, the greater its concentration and the lower the freezing point of the juice. In this way, the continued freezing of food must be carried out under conditions where the temperature is greatly reduced. It can be seen that the amount of frozen water that freezes in food increases with the extension of freezing time and the decrease in freezing temperature ^[2] .