Posted on 22 October 2009 by

Reader Question: Canning Tomato Juice

tomato-juice2By Vanessa Richins

Jim says:

“In the canning process, it calls to add 2 Tbl lemon juice to quart jars, totally blew it and forgot.  They are all sealed correctly. Should it be thrown away? Can I reprocess with the lemon juice, or reboil and go through processing again?”

Hi Jim! First, we should explore why they’re asking you to add lemon juice to your tomato juice.

The main culprit you’re trying to battle when you’re canning foods is a bacteria called Clostridium botulinum, which occurs in the soil and is the cause of botulism, a paralyzing illness.

There are two basic styles of canning – boiling and pressure. The method you use is determined by what you are canning. If you are working with highly acidic (below 4.6 pH) fruits and vegetables (which includes many tomatoes), you can use boiling, since the acidity itself is enough to prevent the Clostridium botulinum from growing. If the pH is above that, high heat pressure canning needs to be used.

Not all tomatoes are created alike.

As the University of Minnesota Extension office points out, “Unfortunately, a few varieties may have a pH above or close to 4.6. These include Ace, Ace 55VF, Beefmaster Hybrid, Big Early Hybrid, Big Girl, Big Set, Burpee VF Hybrid, Cal Ace, Delicious, Fireball, Garden State, Royal Chico, and San Marzano.”

As a precaution, the USDA now recommends you always add some acid, like lemon juice, to any variety of tomato product you are canning. You can balance it out with a little sugar if needed.

My research shows that you can safely redo jars within 24-48 hours by going through the whole process again with newly sterilized jars. You could also put them in the refrigerator during that period until you are ready to re-can, as Ball advised you. Otherwise, I would have to unfortunately advise that you throw them away to be safe.

Good luck!

Leave a Reply

Recent Comments