I have a small Presto pressure cooker (this model). It's intended for cooking food, not for canning. It has a 15 pound pressure regulator. I've used it for canning green beans (it fits four pint jars) because it's the only one I have. My first question is about safety. The BBB recipe says to process pints for 20 minutes at 10 pounds of pressure. I process them for 20 minutes, even though it's 15 pounds of pressure. Is this okay? I've assumed it is, since it is achieving a higher temperature with the extra 5 pounds of pressure.

The only downside I see is that my cooker only fits 4 pint jars. Is there any other reason why I should buy a product that is intended specifically for canning?

Thanks very much for your advice.

-Anne

Technically, no. They would be considered under-processed. Plus the texture/quality is affected. To insure safe consumption you will need to boil them for at least 10 mins after opening the jar.

Is there any other reason why I should buy a product that is intended specifically for canning?

Most definitely. Small cookers are not approved for canning for several reasons but the most important one is because the processing times are computed based on the larger canners and the heat up time and cool down times are calculated into those processing times.

The small cookers heat up and cool down substantially faster so the food is held at pressure for a shorter period of time than is recommended. That voids all the recommended processing times. The time would have to be increased to compensate but how much to increase is unknown and would vary from pot size to pot size.

Green beans are nothing to risk with as they are one of the more common sources of botulism toxicity.

The minimal size of pressure canner recommended by the guidelines must be able to hold and process 4 quarts jars for the processing times to be valid.

Your choice.

Dave

You said if I boil them for at least 10 minutes after opening, they are safe to eat. So, if I have a recipe that calls for baking them in a casserole (in the oven for 30 minutes, say), I still boil them first? I'm thinking yes, since the center of the casserole wouldn't get enough heat.

Thanks as always!

Please note that the guidelines recommend pitching them jars and all un-opened to avoid cross-contamination. Most of us find that to be a bit extreme but care is warranted when dealing with them.

Dave

I'm glad I asked the question. I'm going to order a 16-qt pressure canner, which will be nice anyway. Only being able to can 4 pint jars at a time is kind of a drag.

I really appreciate the information and advice. Thanks again!