Packaging of frozen food

The most important aspect of freezing food is the packaging in which it is to be frozen. Appropriate packaging is essential to prevent any damages to the food in freezing, prevent mixing of flavours and also to easily distinguish foods and separate them for storing. For this very important function of packaging the frozen food, the type of packaging and the quality of packaging is an important factor.

The prime purpose of packaging is to keep food from drying out and to preserve nutritive value, flavor, texture and color. A good packaging material should have the following characteristics:

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• Moisture/vapor-proof or at least moisture resistant.

• Made of food grade material, i.e. designed to be used for food products.

• Durable and leak-proof.

• Doesn't become brittle and crack at low temperatures.

• Resistant to oil, grease or water.

• Protect foods from off flavors and odors.

• Easy to fill and seal.

• Easy to mark and store.

The packaging to be done will depend on the type of food to be frozen, personal preference and availability. The various types of packaging include:

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Type of Packaging	Note
Ordinary waxed paper and paper cartons from ice cream and milk	Packaging not sufficiently moisture/vapor-resistant for long-time freezer storage.
Rigid containers are made of plastic, glass, aluminum and heavily waxed cardboard	Suitable for all packs. These are often reusable.
Glass jars	Should be made for the purpose. Do not use regular, narrow-mouth canning jars for freezing foods packed in liquid, as expansion of the liquid could cause the jar to break at the neck.
Cans	Shortening and coffee cans are good for packaging delicate foods. Line the can with a food-storage bag and seal the lid with freezer tape because they are not airtight.
Baking dishes	Can be used for freezing, heating and serving. Dishes may be covered with a heavy aluminum foil taped with freezer tape.
Ice cube trays	Good for freezing foods in small amounts. Freeze food until firm and then transfer to freezer bags.
Bags and sheets of moisture/vapor-resistant materials and heavy-duty foil	Suitable for dry packed vegetables and fruits, meat, fish or poultry. Bags can also be used for liquid packs. Protective cardboard cartons may be used to protect bags and sheets from tearing and to make stacking easier.
Laminated papers	Made of various combinations of paper, metal foil and/or cellophane. These are suitable for dry packed vegetables and fruits, meats, fish and poultry. Laminated papers are also used as protective over-wrap.

The essentials of packaging and storing:

• Cool all foods and syrup before packing. This speeds up freezing and helps retain natural color, flavor and texture of food.
• Pack foods in quantities that will be used at one time.
• Most foods require head space between the packed food and the closure for expansion as the food freezes. Loose packing vegetables, such as asparagus and broccoli, bony pieces of meat, tray-packed foods and breads, do not need head space.
• Pack foods tightly to cut down on the amount of air in the package.
• Run a nonmetal utensil, such as a rubber scraper handle, around the inside of the container to eliminate air pockets.
• When wrapping food, press out as much air as possible and mold the wrapping as close to the food as possible.
• When packing food in bags, press the air from the bags. Beginning at the bottom of the bag, press firmly moving toward the top of the bag to prevent air from re-entering or force the air out by placing the filled bag in a bowl of cold water taking care that no water enters the bag. Seal either method by twisting and folding back the top of the bag and securing with string, good quality rubber band, strip of coated wire or other sealing device. Many bags may be heat sealed, and some have a tongue-in-groove seal built in.
• Keep sealing edges free from moisture or food so they’ll make a good closure.
• When using tape, it should be freezer tape, designed for use in the freezer. The adhesive remains effective at low temperature.
• Label each package with name of product, date, amount and any added ingredients. Use freezer tape, freezer marking pens or crayons, or gummed labels made especially for freezer use.
• Freeze foods at 0 F or lower. To facilitate more rapid freezing, set the freezer at minus 10 F about 24 hours in advance of adding unfrozen foods.
•  Freeze foods as soon as they are packaged and sealed.
• Do not overload the freezer with unfrozen food. Add only the amount that will freeze within 24 hours. Overloading slows down the freezing rate, and foods that freeze too slowly may lose their quality.
• Place packages against freezing plates or coils. Leave space between packages so air can circulate freely. After freezing, store packages close together.
• Arrange packages so you use those that have been in the freezer the longest first.

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Post by Faiz Lahori