I have been using my large chest freezer as a cool room for storing my grains and dry goods. In this humid climate, especially in summer, it's truly been a very good way of making sure bugs and mildew don't spoil our food and thus we avoid wastage. Using the freezer this way I wasn't concerned if the electricity went off, I knew that no matter what, that food would be fine.
However, since we started eating a little bit of meat each week, I now have a small amount of meat in the freezer and I have changed my cavalier attitude towards the contents of the freezer. Now I see it as an active part of my food preservation and have been freezing more. I would be much happier with my freezer if we had our solar panels, but I have to deal with what we have now, so I don't think about what I hope to have in the future and make sure my freezer doesn't use more electricity than necessary. I do this by not putting warm or hot food in the freezer and keeping it full, even if it's with containers of frozen water.
Freezing is a very good way of preserving food. It does not sterilise food, like a water bath or pressure canner does, but it slows down changes in food and retards the growth of microorganisms due to the extreme cold. It doesn't require special equipment, except the freezer itself, and it doesn't take much time. It's much faster than using a water bath and if treated properly, the food usually retains its nutrition, texture and colour. I believe freezing is the best method of preserving food but it does cost money to keep the freezer going and you run the risk of losing the food to spoilage if your power is cut for a length of time. Our freezer is very efficient and since our local transformer was replaced a few years ago, we very rarely have power cuts.
For the best results, keep your freezer below minus 18 C (minus 0.04F). While freezing will not kill the bacteria that causes botulism, if the bacteria is present, it cannot multiply and produce harmful toxins in a freezer kept at under minus 18C. The top of your fridge freezer isn't cold enough for long term storage. It will freeze food but not at a temperature low enough to keep food for months. When we know we will add new foods to our freezer, I set the temperature lower 24 hours before adding the food. That allows the food to freeze faster. The faster food freezes, the less damage there is to the cell wall structure of the food.
There are two main points I always take care with when freezing food I want to store for a long time: blanching and wrapping. Blanching vegetables before freezing them inactivates enzymes that can spoil the food and it helps kills some micro-organisms on the surface of the vegetables. Blanching will also collapse the vegetables and that helps pack more food into a small space. I tend to blanch all vegetables I freeze because generally I don't know when they'll be used. But if you know you'll only store something for a couple of weeks, it doesn't need to be blanched.
Blanching vegetables <- click for information from the National Center for Home Food Preservation
Wash all the vegetables thoroughly. Prepare a deep pot of boiling water and have a colander and tongs ready. Fill your kitchen sinks or large bowls with cold water and ice. Blanch small amounts and time them from the moment the water returns to the boil after the vegetables have gone into the water. There is a chart here for the times most vegetables need. When blanching is complete, remove them from the boiling water and plunge the vegetables into the iced water to prevent overheating. When the vegetable is cool, drain in a colander, wrap and place in the freezer.
I always use freezer bags for vegetables. Place the vegetable into the bag and press gently to expel as much air as possible. If you can move the contents of the bag around a little to make a flat square package, do that because it will stack well in the freezer. Small packs are better than big ones. Make sure you mark the bag or container with the type of food and the date it was added to the freezer.
Freezing soup or sauce
This can be packed into a plastic container, suitable for freezing. Some plastic containers will crack when subjected to very low temperatures so make sure you have the right kind of container. Don't freeze glass, most of it will break.
Fill the container almost to the top. Food expands when it freezes so make sure you leave some headspace, just as you would when you're canning/bottling. The larger the container, the more headspace you'll need. For example, about 500 mls (one pint) will require a headspace of about 13mm (½ inch) and the same food in a 1 litre pack (1 quart) needs about 25 mm (1 inch). If you're freezing commercial milk, you might need to take a little bit out of the bottle to allow for expansion. Defrost milk in the fridge.
It's a very good idea to keep a record of what you have in your freezer. This will allow you to manage your frozen food effectively. A freezer, particularly a chest freezer, is a difficult space to manage and a record of what goes in, with the date, and what comes out, will give you an accurate freezer inventory at any time without you having to unpack it to see what's at the bottom.
If the power goes off
If you know the power will be off on a particular day, turn up the power the day before. Then, when the power goes off, unplug the freezer and cover it with blankets or quilts to insulate it. Don't open the freezer until the power comes on again. When the power comes back on, plug the freezer in again and switch it on. A freezer will usually be able to keep food safe this way for two days.
Position of a freezer
If your freezer is under a window, make sure the sun doesn't shine on it. If sun comes through that window, put up a curtain.
Having a deep freezer will allow you to store all manner of raw and cooked foods for several months, depending on the food. You'll be able to take advantage of buying meat in bulk and store harvests from your garden, or cheap buys at the markets, for the months to come. If you're new to freezing, it would be a good idea to find a book on the subject at the library so you know the ins and outs of it. If you do, you will make food storage in your home a safe and easy option.
I am looking forward to reading the ways you freeze food, particularly leftovers.