We’ve dealt with water bath canning tomatoes and peppers safely here before. The tomatoes used lemon juice. The peppers were pickled in vinegar. When water bath canning lower acid produce, the heat of the boil does a fine job of knocking out most bacteria, molds and enzymes. Just not quite all of them. The addition of acid in the form of vinegar or citric acid (lemon or lime juice) will lower the pH, making it less hospitable to bacterial growth.
The same rule applies to canning salsa, of course. Fortunately, vinegar and lime juice both play very well with the bold and beckoning flavors of a well-made salsa. It stores well, travels well, and it’s pretty enough to put a bow on and tuck under some lucky salsa lover’s tree this holiday season.
Variations on this recipe include roasting the tomatoes before use, experimenting with herbs or leaving some or all of the seeds in when adding the jalapeno to bring the heat. If adjusting the recipe, though, be attentive to the ratio of tomatoes and other vegetables to the acidic elements (vinegar and lime juice). Balance is essential for a safe and successful preservation of the low-acid harvest.
1 cup jalapenos, seeded and chopped
1 1/2 cup bell peppers, seeded and chopped
1 1/2 cup onion, chopped
4 cloves garlic, minced
1/2 cup fresh parsley, chopped
1 tablespoon salt
1/2 cup cider vinegar
1/4 cup lime juice
Combine all ingredients in a large, heavy pot and bring to boil at medium-high heat.
Reduce heat to medium and simmer 10 minutes.
Ladle salsa into sterile pint jars, leaving 1/2” headspace.
Seal jars with bands and lids and process 15 minutes in water bath.
Originally: How to Can Salsa