Canning is making a comeback. It may be one of the few businesses that are doing well with the economic downturn.

Bernardin, the home canning supplier, reports sales were up 12 per cent last year and 24 per cent in the first part of this year.

Before you join in and dig out grandma's old canning equipment, be aware of new techniques to keep food fresher and prevent Botulism.

See related links: BC Centre for Disease Control and Botulism risk

The recommended heat processing time for making jam is now 10 minutes. That's up from five.

All canned food must be heat processed, the acidity of food determines what device you need to use.

Low acid foods like vegetables need a pressure canner that will heat the food in the jars to 240 degrees Fahrenheit or 116 degrees Celsius.

Take note that tomatoes are no longer considered high acid and now need special care when canning.

That means adding lemon juice or citric acid to each jar as you fill it.

The seal is very important. Once the jar has cooled for 24 hours, check the seal by pressing on the lid.

If it's concave and doesn't move, the seal is good.

If it makes a clicking sound, the seal is not right. And that's a Botulism risk. Botulism is fatal 10 per cent of the time, even if treated properly.

So if you have any doubt about your home canned food just throw it out.

With a report by CTV British Columbia's Chris Olsen