Pressure cookers are used for canning.
Pressure canning extends the lifetime of pasta sauces for 2-5 years. Although some sources list high-acid foods as only being good for 18 months, that's because they assume they were boil-canned, not pressure canned. Tomatoes in season aren't expensive, so even if you haven't grown your own tomatoes, canning can still save money. Canning foods in season is also "green," since it promotes eating local produce and reduces the man-hours and fossil fuels needed to transport fresh produce.
Instructions
1. Clean canning jars and bands with hot soapy water and rinse thoroughly. Always use fresh lids.
2. Heat the jars and lids in a pan. This is not to sterilize them, but to keep the jars from breaking when you fill them with hot tomato sauce. Turn the jars upside down in a pan with three inches of water in it. Boil the water and then turn the heat off. Leave the jars in the pan until you're ready to fill them.
3. Cook your sauce according to your recipe. If you don't have a time-tested or family tomato sauce with meat, you'll find plenty of recipes in Italian cookbooks or online recipe sites.
4. Remove one jar at a time and fill it with sauce, leaving one inch of space at the top of the jar.
5. Clean the neck of the jar to remove any spilled sauce that could block a tight seal. Place the lid on the jar and hand tighten the band on the jar.
6. Put four inches of water in the pressure cooker and then put in the jars.
7. Put the lid on the pressure cooker and turn on the heat. Leave the vents open for 10 minutes to remove the air from the inside. If you have a weighted canning pressure cooker, leave the weight off for those 10 minutes. After that, close the vents and add the weight if applicable.
8. Reduce the heat, but keep the cooker at pressure. Follow your manufacturer's instructions on do that.
9. Leave the pressure canner at pressure for 60 minutes for pints of sauce and for 70 minutes for quarts. When the time is up, turn off the heat and allow the pressure cooker to equalize. Once that's done, remove the jars using a jar lifter and place them somewhere to cool completely, often overnight.
10. Check the seal after the jars have cooled by pressing down on the center of the lid; it shouldn't move and should already be sealed. Remove the bands and store the jars.
Tags: pressure cooker, turn heat, fill them, heat Leave, inches water, tomato sauce