The lining is placed against the food. Heavyweight aluminum foil, plastic, cellophane, pliofilm and polyethylene are also moisture and vapor proof, pliable and durable. Plastic freezer bags may be protected with a cardboard box or stockinette to keep from tearing. Rectangular cartons will stack easier and make better use of freezer space than irregularly shaped packages. Secure plastic bags by tying the end in a knot or by using a rubber- band, covered wire twist or string.
Rigid containers hold their shape, stand upright and stack well.
Be sure they have tight-fitting lids. They may be plastic containers, which are available in square and round shapes. Heavily waxed cardboard containers, with plastic or waxed lids, are also good to use. Canning-freezing jars are best because they are tempered to withstand both extreme cold and heat. Handle glass carefully because rough handling or sudden change in temperature can break the glass.