Quick frozen generally refers to the use of modern freezing technology in the shortest possible time, to reduced the food temperature to below the freezing point of a certain temperature, so that it contains all or most of the moisture content with the food outside the formation of scattered heat to become reasonable tiny ice crystals minimize the life activities of microorganisms in food and the liquid moisture necessary for the biochemical changes of food nutrients to achieve a maximum level of preserving the original natural quality of food.
General Individual Quick Freezing foods should have the following five elements
1. Frozen to a -30 ~ -18 ℃, and should be completed in about 20 min;
2. Temperature rapidly reduced to microbial growth activity temperature, is conducive to the inhibition of microorganisms of the activities and enzymatic biochemical reactions;
3. Frozen food center temperature to reach below -18 ~ a 15 ℃, the frozen food moisture to form numerous needle-shaped ice crystals, its diameter should be less than 100μm, to avoid the formation of larger particles in the intercellular space ice crystals;
4, The distribution of ice crystals is similar to the distribution of liquid water in the raw materials, which has little damage to the cell structure;
5. When the foods are thawed, the ice crystals can quickly be re-absorbed by the cells without loss of juice.
In general, Quick frozen foods should have the following advantages:
1. Avoiding the formation of large ice crystals between the cells;
2. Reducing the extracellular moisture in the cells, reducing the loss of juice when the foods are thawed;
3. Concentration of residual water decreased the risk;
4. The food temperature rapidly reduced to the growth of microorganisms, activity temperature is conducive to the inhibition of microbial growth and biochemical reactions;
5. Food in the frozen equipment residence time is short, help to improve the utilization of equipment and continuous production.
Disadvantages OF Individual Quick Freezing: a one-time investment in equipment, the product cost is relatively high