I wouldn't trust those commercial jelly jars for storing on the shelf. They are meant to be used once under industrial processing, and not intended for multiple use under home canning methods.

They might be OK for the freezer though. But do use proper home canning jars with the lids/rings meant for home processing in the future.

I've been canning for 30 years. I know the difference between safety recommendations and what is actually safe in my individual conditions. I can gauge the safety of my jams. Considering older jam makers just added a layer of grease to the top of their crockery preserves, i think I will survive. I would not recommend this to a novice who doesn't know the science behind the food safety or what can and does go wrong. I don't work for the USDA nor am I in teaching mode right now. I knew when I posted this the safety police would jump on it. Again, what is recommended for the general public is what makes it absolutely safe for anyone who might make any possible mistake. So by all means follow that guideline. But I am happy to be able to do what I did. Also, folks used to follow the old paraffin seal rules and use all kinds of jars. The only reason they stopped recommending it is because it is not fool proof and hot wax is tricky. Air can get in and molds can form and folks can ignore both conditions and eat the jam . . .

Edited to add the crocks were not sealed with "grease." That was my shortcut phrase. It was tallow which is rendered beef fat. The rendering clarified it from all the impurities (proteins, etc.) that could cause it to go rancid. Still, the seal could be compromised and there could be problems. High sugar content and acidity deals with some of that. Still, preserved fruit was a luxury and usually eating with a special spoon from a special cut glass dish. Drying was the more common preservation method. And a lot of monotony of apples, apples, apples.

It's all good :) and my apologies- when you said this:

"Last take away was how easily I could reuse old glass jam jars, with the lids. They sealed up fine and no breakage issues during processing. I don't often buy commercial jam, but now when I do I'm saving the jars to can with."

It sounded like this was a recent discovery to you that you started doing, not that you have been reusing commercial jars for the last 30 years.

I'm not really a food safety police- I let my accreditation expire a couple years back when I moved to the boonies :) Didn't need to keep doling out the training and recertification fees out here.

Sorry for my knee jerk reaction. Here's the science behind my comment. It is always recommended NOT to use commercial jars because they are not of the same heft/thermal shock resistance as jars sold specifically for home canning. The risk with the glass part of the jar from a random store product, is that it is much easier to break under the wide variety of boiling water and freezing conditions that it might be put to in a home canning situation by the average home canner. Small cracks and chip can also compromise the seal. I myself am an inveterate jar dropper/jar jostler, and have had a few memorable thermal shock mistakes in my day . . .

The second problem is the lids. The enamel or metal coating is thin and could get nicked or broken, causing the seal to fail or rust to get a foothold. They are not designed for reuse.

However, as someone who has canned for 30 years and also studied and used old canning tools and techniques, I find myself being cynical and disappointed at how increasingly wasteful the process has become. I have seen canning jars and lids get thinner over the years, with obvious research going in to just how thin they can make the lid coatings and rubber gasket and jar, so that it can withstand one use, but is likely to fail upon a second or god-forbid a third . . . Quite frankly modern lids have such thin rubber that I am starting to find seal failures upon first use occasionally.

I've also seen in recent times, glass, which is a relatively easy product to recycle, become un-recyclable due to China stopping accepting it. That is pretty ironic during times we decry the loss of American jobs. But we have been conditioned to not want or like the recycled glass products by the plastics industry, so they are no longer economical. And what good are canning jars and rubber gasket that you can re-use for thirty years, where's the profit in that? Hence the development of new safety rules and the disappearance of the older jars and seals from the market. Always with the sly safety reference, but if you understand the science, it's mostly marketing. Some are a little less "fool-proof" than the newer methods, but then why have we become such a group of fools? (Rhetorical and exaggerated comment). Not saying it's not great to develop easier canning methods, for those novice or wanting to extend as little effort as possible, but that doesn't make older methods unsafe when employed by someone who knows what they are doing.

Not pooh poohing real safety science mind you. But what is no longer or never rigorously tested, is not necessarily safe or not safe. We can no longer say because there is no data . . .

I rarely buy commercial jams. So when I did due to just having a canning dry spell, and also a canning jar shortage, I looked at the jars from some recently purchased jams, and said, "No reason I can't reuse these. Glass looks thick enough and jar lids are fresh, good rubber, and have pop top so I can monitor the seal. Not saying this is going to become my "go to" way of doing it, but at least two glass jars were kept from the landfill!

Bon Maman peach preserves is my favorite jam/jelly and how nice you have some of your own!

I love their preserves too., (Bon Maman). I save those jars too, but I use them with kids/students for catching bugs . . . easy to get them inside due to the large opening . . .the bugs not the kids . . . :)