Recently i started to do some home-made canning. The procedure I use is

  1. Use a pressure cooker to build the jars (cristal ones) for about 10 minutes at 120C.
  2. Cook my vegetables (normally tomatoes, garlic, capsicum, eggplant, zuchini) the whole mix surely has a ph over 4.6 which is where the Clostridium botulinum lives.
  3. Put the cooked vegatables in the cristal jars (which will still be hot), close them, and put them back into the pressure cooker.
  4. Cook the closed jars for 20-25 minutes at 120C

My understanding is that botulism is a very serious disease, the most concerning part is that it does not alter the taste, color or texture of the food.

Currently I consume my canned food within 1 week.

The question is, given that I use 120C degrees when cooking, can I be reasonably safe? Is there a significant risk?

Follow up question: I would like to not only store my cooked vegetables, but also cook them with tofu or chicken and then preserve them using the same procedure, however I have not done so as I know tofu has quite a high PH. Would it be safe to use vegetables + tofu/chicken in the preserves?

  • Also, it's better to ask one question per... well.. question as we don't charge extra for multiple questions and the more questions you ask in one question the less likely it is for you to find an expert that can answer all if your questions in one go ;-)
    – Fabby
    Commented Sep 16, 2018 at 7:45

1 Answer 1


I recommrnd you pressure cook for 30 minutes at 120C, not your current 20 to 25 minutes. Regardess of pH, low or high, you have already killed the spores and the high temperature is needed to destroy the residual toxins. Your food should be safe to consume for at least least two years after you canned it.

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