Freezing food is the process in which the Strewberries temperature is reduced by freezing water in the cellular juices and interfacial distances of the tissue and converting it into ice crystals, which results in the concentration of dissolved substances in the non-freezing water and this reduces the water activity in theStrewberries and the materials resulting from the freezing with deep temperatures of - 20 to -40 degrees Celsius.
It remains without physical or chemical changes for a long time, the preservative factor in this technique is by combining both low temperature and low water activity (Arising from the concentration of dissolved substances in a small amount of non-freezing water) and the steps that occur before freezing, such as boiling.
To preserve Strewberries for a long time by preventing the growth of microorganisms at (-10C) or stop the chemical reactions and enzymatic activity at (-18C) and this may be available in household freezers, but when freezing on a commercial scale, the temperature is reduced to (-29C), so that the frozen food can be obtained in high quality.
The freezing industry has spread for a number of reasons:-
1) Preserve extra products from Strewberries.
2) Availability in the off-season.
3) Easy operation, save time and cheap.
4) Improving the properties of the product during its preparation in terms of cleaning, peeling and sorting. Strewberries especially those eaten cooked represent a large sector of frozen food. Egyptian standards specify some general conditions that must be met in the final frozen product.Strawberries are inspected and washed in an international dishwasher. They move to a double bar, where the stems and petals are removed.
It is placed on the bottom strip. The peeled strawberries go to the dryer to remove the surface moisture.
At the end of the dryer, strawberries are collected in suitable boxes, arranged in aggregates