Preserve it! Series: "Dry Canning," an Internet Sensation, is Inherently Dangerous
Dry canning vegetables doesn't ensure even heating.
Another “homemade” canning method (in other words, someone made it up themselves) has been making the internet rounds recently, which involves pressure canning vegetables without any added liquids. The food, either cooked or raw, is simply put in a jar and then processed according to a recipe’s pressure and time specifications. It may seem appealling – proponents say that the lack of added liquid results in a firmer vegetable after canning. Unfortunately, this is an unsafe practice and it can be potentially hazardous. Don’t do it.
Why is it unsafe? The pressure canning process is designed to destroy the spores of Clostridium botulinum, which can produce a toxin that causes botulism – a disease that can be fatal. To kill these spores and ensure a safe product, liquid is required along with the vegetable pieces so that heat can circulate properly and penetrate throughout the entire jar. Further, bacteria and their spores are more sensitive to wet heat than dry heat. Without liquid, the bacteria would be killed off much more slowly. Studies would be needed to determine if “dry canning” vegetables could be done safely and if so, what processing adjustments would be necessary.
But what about folks who have used the dry canning method and not gotten sick? It is, of course, possible to improperly process food and not get sick. But this is merely luck. Bacteria are randomly distributed throughout our environment. You could process one batch of food and have no problem, but another time bacteria could be present that can make you ill – or worse. Why rely on luck?
To be safe, always use a current research-based recipe from a reputable source and carefully follow all steps in the process, including preparing the food, filling the jars, and using the stated time and pressure (adjusted for altitude as necessary).
For further information visit the National Center for Home Food Preservation (NCHFP) or visit your local Cooperative Extension office.
Brought to you by the UC Master Food Preservers of El Dorado County
Last updated July 2025