- Select fruit in its prime. Make sure not to can underripe or overripe fruit.
- Cook the fruit in a heavy-bottomed pan to avoid burning.
- Skim off the foam during cooking if you like, but you don’t have to; it won’t affect the taste.
- Choose easy-to-fill wide-mouth mason jars that close with flat caps and screw-on rims. Two good brands are Ball and Kerr.
- Buy new caps for every new sealing.
- Use a big pot with a fitted rack to boil the canned fruit, so the jars don’t touch the bottom.
- Be sure the jars fit easily in the pot. You will get better results if the rims don’t touch.
- Consider investing in a home pressure canner, which cuts the processing time in half. They are available at specialty kitchenware shops from about $60.
- Store preserves in a cool, dark place; sunlight can bleach out the color.
- Refrigerate canned foods after opening.