1. Put your food stuffs in jars in a pressure cooker (required to get a sufficiently high temperature), different foods will take varying amount of water and seasoning if desired.
2. Place vacuum lids on top of jars.
3. Apply heat for as long as it takes to kill all the bad bacteria (check google).
4. Vaccuum will form in jars and seal lids as they cool.
5. Screw on tops. These protect the lids from being knocked loose. They are not their to provide a seal.
When you open a jar, ensure that the vacuum seal is still good. If not discard. Metal vacuum lids cannot be reused.
Most grocery stores carry mason jars. Wash them with heat in the dishwasher before you use them.
Don’t recommend canning corn. Steam, cut off cob and freeze.
It is now recommended that you can tomatoes using a pressure cooker. I think the reason is that many of the new varieties of tomatoes are not as acidic as they once were.
The best way to can is to check your home extension office in your county. They usually have up to date canning information on their websites. There are alot of great canning websites on the internet.
It depends on what you want to can as to which method you are using. I’ve canned jams, jellies, salsa, tomato soup, spaghetti sauce, vegetable and chicken soups, tomatoes, bbq sauce, pickles, and various fruits and pie fillings over the years. There are some things we prefer frozen. Green beans for example taste entirely different frozen than they do canned. I prefer the frozen as they taste more like fresh green beans.
The advantage to canning over freezing is that canned goods last longer and do not rely on electricity to maintain. It also frees up room in your freezer for storing other things that cannot be frozen like fresh meat and make ahead meals etc.
Buy good equipment. A good pressure canner and hot water bath enamel canner. Use only jars made for canning. I prefer always buying wide mouth as they are easier to get some things into like pickles and pears. Size of jars depends on what you are canning. Jams & jellies I do in half pints, tomatoes in quarts. I use alot of pints for applesauce and salsa. And new fresh tops are used every time you can. You can reuse the rings. You’ll need a jar lifter and a magnetic lid lifter to get the lids out of the hot water that you soak them in before using. Follow all directions and times exactly. Ball makes a good canning book and they sell it on their website.
I love canning and made my own dill pickle relish last year. Great stuff!
Some sites I use for both recipes and advice but always follow extension recommendations:
www.canningusa.com
http://www.recipecottage.com/preserving/
http://www.mountain-breeze.com/kitchen/canning/index.html
http://www.homecanning.com/
http://www.pickyourown.org/allaboutcanning.htm
http://www.geocities.com/Heartland/Acres/1012/canning.html
The new Ball canning site:
http://www.freshpreserving.com/
An example of a University Extension canning website:
http://edis.ifas.ufl.edu/TOPIC_Canning_Food
Have fun!