Freezers should be set at -17.8 degrees Celsius for optimal food preservation. The temperature should never reach above 0-15 degrees C. Many freezers have internal thermometers indicating the temperature. If your freezer doesn't have one, place one inside the main freezer compartment to monitor temperature levels.
Chest freezers consist of one large space for frozen foods, with hanging baskets for smaller items, and a top-lifting lid. This style is typically more energy-efficient than other styles, keeps food colder easier and offers the most usable space for the size of freezer. However, it can be difficult to access items buried below others in the depths of the freezer, and the chest style takes up a lot of floor space, as well as posing a safety hazard for young children who can become trapped inside.
Upright freezers resemble refrigerators in style, with a full-length door and inner shelves and bins. The upright style has a smaller footprint than the chest style, making it a better fit for smaller homes. Upright freezers provide convenient access to their contents, but the shelves and other organizational features reduce the usable space significantly compared with a chest freezer. An upright freezer is also generally more expensive and is less energy-efficient than a chest freezer.
Combined Refrigerator and Freezer
Most refrigerators have a freezer either above or below the refrigerator compartment. If the freezer has a separate door, it can maintain its temperature reasonably well, but because it is more frequently opened, it is more difficult to keep the temperature at 0 degrees than with chest and upright freezers. Some refrigerators have a small freezer compartment within the main fridge space. These freezers generally cannot maintain an optimal temperature, and any food kept in them should be used within a week.
No matter what type of freezer you own, the way you package your food and use the freezer impacts how efficiently it preserves the food. Wrap food in freezer paper, freezer bags, vacuum-sealed bags and other air- and moisture-proof products to prevent freezer burn. Freeze food rapidly, allowing space between it and other items in the freezer until it is fully frozen. Then pack the food close together for storage. A full freezer is more efficient than a half-empty one. Label packages with names and dates to make it easy to identify what you need and to rotate food so the oldest packages are used first.