When cooking for the freezer it is important to use only quality fresh food. Freezing will not improve food and food to be frozen must be of the best quality, hygenically prepared, and correctly packed and stored. Keep all utensils, materials, work surfaces and hands scrupulously clean and work quickly, handling the food as little as possible.
For best results, cool food as rapidly as possible before freezing, in order to preserve it in prime condition and to avoid contamination by harmful bacteria.
All materials or containers used for packaging must be moisture and vapour proof. Packaging must also protect food from damage during storage and be durable at low temperatures. All glass containers and serving dishes should be tested for toughness at low temperatures. To do this, fill them with water, leaving a 2.5 cm/1 inch headspace, place in a freezer bag and freeze. (Always pack glass in a freezer bag, in any case; should the container shatter, the pieces will be held safely in the bag.)
Correct and careful packaging of food is essential. One of the results of bad packaging is dehydration, which takes place if air is not completely excluded from the packaging before freezing. Moisture and juices are lost from the food and in extreme cases freezer burn appears on the surface of the food in the form of greyish or brown patches. These are not harmful and can be removed when the food is thawed. Oxidation is another result of bad packaging and occurs in products with a high fat content. Oyxgen penetrates animal tissues, causing fats to go rancid. Correct wrapping and the removal of air from packages prevents oxidation occuring.
Always overwrap highly spiced or strong-smelling foods in freezer bags or heavy-duty foil. Insufficently wrapped foods containing garlic and onions, for example, will transfer their flavours to foods nearby.
When liquid freezes it expands, so it is neccessary to leave room for this expansion in the package. A headspace of 2-2.5cm/or 3/4-1 inch per 600ml/1 pint/2 1/2cups of liquid is usually sufficient, but a little more is required for tall narrow containers.
Pack food in usuable quantities and label all packages clearly, giving the date of freezing. It is important to keep a record of the contenets of the freezer to ensure that food is not kept beyond its recommended storage time.
Many frozen cooked fooods can be reheated without thawing, either in the oven or microwave.
When reheating soups, stews or casseroles always make sure that the cooked food is heated throughly before serving.