pear tart said:
Okay, so yesterday my husband and Ispent afruitful afternoon canning tomatoes and learning the ropes (so to speak)of pressure canning. Now we‚’re wondering, what did we do wrong, and did we just waste 20 lb. of plum tomatoes?
How full were the jars? It's important to leave enough headspace in the jars for expansion to happen during the heat up phase. And, yes, 1.5 hours is extraordinarily long. Can you send me the page reference you got that from? I think 1.5 hours is for a 1 liter jar of conductive food. For a 1 liter jar with tomatoes, which are acidic, I would estimate 10 to 15 minutes once the pressure has come up.
Here‚’s what we did: We packed raw tomatoes into one-litre jars, added the recommended amount of lemon juice, filled the jars with boiling water, sealed them, then processed them for 1.5hr. Ithink that‚’s an extraordinarily long processing time, but according to Modernist Cuisine, it‚’s afail-safe to ensure that everything reaches optimal temperature for killing any possible toxins. The instruction book that came with our pressure canner recommends 10minutes at 10 lb. pressure.
Here‚’s what we got: Bottles are only about 3/4 full, and there‚’s evidence of leakage into the canner. After they came out of the pressure canner, the tomatoes were floating near the top of the jars, but have since settled to the bottom. The liquid and tomatoes fill only about 3/4 of the jars. They‚’ve also discoloured, indicating, to me at least, that they‚’re seriously overcooked.
A photo would help, but is sounds like air has remained (or leaked) in the jars and combined with the long, high temperature cooking you have degraded the lycopene (red pigment) of the tomato. I would guess the color is brick red to brown now, yes? This almost certainly occurred because the jars started out as much too full and overflowed during the heat up, preventing a good seal from forming during the cool down phase.
Okay, so Iknow that we didn‚’t pack the tomatoes tightly enough. Ihave another case of tomatoes to can today, so will address that problem. What Ineed to know is, are the ones we‚’ve already canned safe to eat? Or is the air space likely to harbour any nasties, and should we just discardthem?
If you have refrigerated the failed jars then, yes, the tomatoes are fine for consumption. If not, the only ones I would use would be those that have a very firm seal when you open them, which indicates that you have a sterile seal.
edit: formatting