RECIPES: Jam session

Many cooks have a bit of trepidation about canning. And with good cause — canned low-acid foods such as vegetables, meats and some tomatoes can harbor harmful organisms if not processed properly. But high-acid foods, including most fruits, pose little risk.

Almost all bacteria, yeast and molds will die when exposed to temperatures between 175 degrees and 210 degrees. The exception is botulinum toxin. Food-borne botulism is rare, but it can be fatal. Which leads us back to the fear that shrouds home canning. While botulinum toxin can survive high heat and little oxygen, it cannot grow below a pH of 4.6.

The good news is most fruits used for jam and jelly making are high acid.

Jordan Champagne's book It Starts With Fruit, includes a handy chart that lists the pH of common fruits as well as pectin levels.