Sorry for being too late for a helpful answer...
My suggestion - FOLLOW INSTRUCTIONS...
"Open the canner and remove the jars at once to a clean, dry place, out of drafts, padded by folded dry towel."
Is it OK if I just pull the canner off the burner when it is "done", and let it cool down on it's own overnight and just take the jars out in the morning? Or do I really need to open it once it is depressureized and cooled?
My understanding is that you're not supposed to do this because you can end up with a flat sour.
"Flat sour spores are not directly pathogenic to people. These organisms only cause spoilage in canned foods if the product is not cooled properly. If not cooled properly, the organism has the potential to grow and decrease the shelf life of the canned foods. A food spoiled by flat sour organisms will produce a sour smell and taste. Flat sour spore testing is of most interest for food processors that want to ensure a long shelf life of a product and to prevent early spoilage." [Environmental Microbiology Laboratory]
I have done it as I am sure lots of others have - ONCE... Was treated with 40% unsealed jars and 60% overcooked. But fortunately no flat sour.
I know - 2:30 or 3:00 in the morning after lots and lots of canning and it is sooooo tempting to do, but PLEASE don't...
Besides, why deprive yourself of that final satisfaction of seeing all your splendid canned food all lined up!
You can tough it out for just those few minutes more.. Really you can.
This ONLY applies to glass canning jars - with tin cans it is entirely different - Pop that valve - Drop that pressure, cool 'em down as quick as possible. BUT DON'T EVEN THINK OF IT WITH GLASS JARS!!!
“My understanding is that you’re not supposed to do this because you can end up with a flat sour. “
Is this something that alters the taste?
“I think I remember DW saying once not to leave them in the canner. But I don’t know why because it’s also been said that the slower they cool, the better.”
I remembered reading something about them being left in the canner, unfortunately, I remembered the wrong thing.
I heard them all pinging in the canner, but left them in overnight. They all look fine, but I guess I should open one and taste them. I used the raw canning option, not preheating/cooking the beans before going in the jars. I noticed the canner stayed really hot for a long time, it was still slightly warm this morning. I wonder if it will have overcooked the beans. Live and learn - that’s what it takes sometimes. Well, now that I’ve done it once, it won’t be so intimidating the next time.