I do my best to post only safe canning recipes here. If I suggest that you put something in a jar and seal it, that means I believe it to be a high-acid mixture safe for canning in a hot water bath. High acidity prevents botulism, and most jams and jellies easily qualify.
That said, I am not a chemist or a certified food-safety expert. Before I make or publish a recipe, if I have any concerns about whether or not it is safe for water bath canning, I do my own research and also discuss it with those who may know more than I do, including master food preservers and food scientists. (I never expected that I would know so many such people!)
I recommend the same to you. If you have any questions about the safety of a canning recipe, take steps to check it out. If you aren’t buddies with a master food preserver, one easy thing to do is contact your state’s cooperative extension office and ask to speak with a canning expert. They are there to help you get the safety information you need.
If you have general questions about how to put food in jars or about safe canning practices, you can contact your co-op extension or check out the National Center for Home Food Preservation website. If you decide not to play by official rules, please be sure you’ve got darned good science and experience backing you up.
Now go get some fruit and have a good time!