JL,

The problem with not enough acid is that the jars could develop botulin toxin. If they do, it is not always immediately apparent. Over time the jar lids will swell and may leak, indicating active organisms. But before it becomes noticeable, an infected jar can seem normal.

Botulism is a serious disease, not often fatal these days–if you know what you’ve got, and it’s correctly diagnosed and treated. If the attack is severe, but doesn’t result in death, the recovery period can take years–basically it attacks your nervous system and you may have to learn to talk again, etc. All of this is intended not to scare the pants off you, but to information you that it is not something you want to play with.

You could open the jars, add the acid, add new lids, and rep-process. However, I would also recommend that you boil the tomatoes for 10 minutes, then put in (clean) jars with acid and new lids, and then re-process. It’s a bit of work, but better than tossing the tomatoes out or risk botulism poisoning.

If the tomatoes were organically field grown and are a traditional canning variety (roma or stupice), they are more likely higher in acid than more modern varieties grown with fertilizers and you may not necessarily need extra acid. But you really have no way of knowing. Since guessing can lead to serious health issues, it’s really best to be safe.

Good luck. I’m processing about 40 lbs of tomatoes today.

Hi JB,

No, you cannot substitute citric acid for vinegar in a salsa recipe. The addition of onions and peppers (low acid vegetaables) requires that you use a carefully tested salsa recipe for canning. PNW0395 is a booklet of salsa recipes specifically formulated to be safe for canning; some use vinegar and some use bottled lemon or lime juice. Download this booklet here: http://oregon.4h.oregonstate.edu/sites/default/files/home_economics/pnw0395.pdf.

Alternatively, you could can tomatoes (whole, quarters, or diced) with citric acid, and use them to make this simple recipe one batch at a time:

Quick and Easy Blender Salsa
Yield: 2 cups

2 cups peeled whole, diced, or crushed fresh or canned tomatoes
1/2 cup coarsely chopped white or green onion
1-2 fresh jalapenos, stemmed, seeded and chopped or 1-2 tablespoons chopped pickled jalapenos
1 clove minced garlic
2 tablespoons coarsely chopped fresh cilantro or parsley or a combination
1 tablespoon fresh lime juice. or to taste
1/2 teaspoon ground cumin, or to taste
1/2 teaspoon salt, or to taste
1/4 teaspoon cayenne, or to taste

1. In a blender or food processor, place all ingredients in the order listed. Cover and pulse the sauce (turn motor on and off) until the texture is chunky or as smooth as desired.
2. Taste and add additional lime juice, cumin, salt, or cayenne. Salsa can be range from mild and sweet to tangy and hot, as preferred.
3. Transfer to a glass or other non-reactive bowl (glazed pottery or wood). Cover and refrigerate until ready to use.

Notes: For best flavor, do not use metal bowls or utensils with salsa as the sauce can take on a “metallic” taste and/or may spoil more quickly. When serving salsa, remove only the amount you intend to use or replenish your dip bowl frequently; keep any unused portion refrigerated.

This salsa recipe may be frozen. It is not tested for canning. For canned salsa, prepare a recipe specifically developed for canning.

Hi Lauren,

Tomatoes have become less acidic due the changes in the way they are grown. So 30 years ago, we did not need to add acid. But, now we do to be safe.

For quart jars, try 2 teaspoons granulated sugar and/or 1 teaspoon salt per jar. For pints, use half those amount. I didn’t like sugar in mine, but many people do. It’s strictly a personal preference things. It also depends on the types of tomatoes you use. I like to can San Marzano (plum type tomato) when doing whole or diced tomatoes. For sauce, another good tomato is Stupice.

I’m glad you and your daughter are canning. I’m glad the younger generation is getting interested in preserving, so we keep the knowledge going.

Christine, The flavor usually develops fully at about 6 weeks. Yes, I’ve had many people say the lemon is very disagreeable. Good thing there is citric acid.

Hi Crystal,

I assume it was pickled pears and melon balls. You cannot can melon balls unless they are pickled, because they are too low in acid. Here is a recipe:

Pickled Melon: Select melons that are full size but green and firm to the touch, including stem area. Wash, halve, and scoop out seeds. Cut about 2 pounds washed melon into 1-inch slices, remove peel, and cut into 1-inch cubes; or, use a melon baller to scoop out balls of melon. In a saucepan, combine 2 ¼ cups cider vinegar, 1 cup water, and 2 ounces fresh peeled and sliced ginger slices, and bring to a boil. Reduce heat, and simmer 5 minutes. Pour hot liquid over melon cubes. Cover and refrigerate melon for 12 to 18 hours. Strain vinegar solution into a large saucepan. Stir in 2/3 cup granulated sugar, 2/3 brown sugar, and ½ teaspoon crushed red pepper (optional), and bring to a boil. Add melon and ginger slices, and return to a boil. Reduce heat, and simmer 1 hour, or until melon turns translucent. Fill hot canning jars with the hot melon chunks and pickling liquid; adjust headspace to 1-nch. Process pickled melon pints for 15 minutes (at 0 to 1,000 feet).

Variation with pears: substitute half of the melon with firm, slightly underripe pears that have been peeled and cored, then cut into 1-inch pieces.

You can buy the book on Amazon: http://www.amazon.com/The-Home-Preserving-Bible-Living/dp/1615641920

You can buy the book on Amazon: http://www.amazon.com/The-Home-Preserving-Bible-Living/dp/1615641920. I assume they will ship to the UK. Not sure the book is available in UK bookstores; any bookstore in the U.S. can order it easily if they don’t have it. So check with a good bookstore in the UK and see if they can, too. Or, send me a plane ticket and I’ll bring one over! LOL

Hi Tori,

No, the amount of vinegar is twice as much as lemon juice:

Quart jars: Add 1⁄4 cup cider vinegar, 2 tablespoons bottled lemon juice, or 1⁄2 teaspoon citric acid powder per quart. To counteract acid flavors or as a matter of preference, add 2 teaspoons granulated sugar and/or 1 teaspoon salt per quart.

Pint jars: Add 2 tablespoons cider vinegar, 1 tablespoon bottled lemon juice, or 1⁄4 teaspoon citric acid powder. To counteract acid flavors or as a matter of preference, add 1 teaspoon granulated sugar and/or 1⁄2 teaspoon salt per pint.

Hi Angelia (what a pretty name!),

The only thing I can think of is you are boiling or heating your lids and you shouldn’t be heating newer lids at all (both Kerr and Ball) . Newer lids use a plastic material that weakens and can fail during storage. Read the box instructions to be sure. If it says simply wash and set aside, then do that…without simmering as we used to do.

Argh. That’s frustrating, since they’re testing sealed, but failing later. But yeah, the sealing compound on the lids was changed some time ago and neither company said a peep. I’ve had a higher than normal seal failure rate–it used to be a rare thing, and now it happens fairly often. Not every batch, but every couple batches there’s 1 or 2. Hopefully NOT heating the lids will do the trick.

Hi Jessica, To acidify tomatoes to make them safe for canning, add 1⁄4 teaspoon to pint jars and 1⁄2 teaspoon to quart jars. You just add the citric acid to the jar, and then fill with tomatoes using the packing method you have chosen (e.g. crushed tomatoes hot pack, whole peeled tomatoes cold pack, or whatever).

Along with citric acid, you may also want to add salt and/or sugar. (Personally, I add some salt, but I don’t like added sugar. Both are a matter of personal preference. Both help told color and flavor, but do not affect safety). If you want to add either one, try 1/2 tsp. salt per pint and/or 1-1/2 tsp. sugar. Keep notes (I simply write it on the lid–no guessing!) and then adjust next year depending on your preferences.