I thought I remembered a thread on jam-making, but now can't find it.  So, a new thread to ask my jam questions.

We went to a u-pick area last weekend, and it's truly amazing how much fruit two enthusiastic children can pick in about fifteen minutes.  So, I set out to make jam, a first for me.  How hard could it be, right?  I got a box of Sure-Jell and some jars and lids.  Much success - really, it isn't hard.  My only complaint was that I found the jam (strawberry with 1 cup of boysenberries subbed in) too sweet for my tastes.  So, now enthusiastic about jam-making, still in possession of my mother's giant pot and steamer insert, and still with several flats of fruit to use, I got a box of the low-sugar Sure-Jell and made a peach-strawberry jam.  Also much success.  (just did the low sugar recipe; no artificial sweeteners, perish the thought). 

My question is about these stern warnings about following the recipe *exactly*, even cautioning you to level the cups of sugar with a flat edge.  Really?  Really? Wouldn't one batch of strawberries to the next vary enough in natural sugars, natural pectin, and natural acids that some variation in the added sugar would be okay?  Isn't that the point of using the Sure-Jell, so it surely jells?  I'm not talking about arbitrarily halving the sugar or anything, but surely some variation can be accomplished without throwing off the chemistry that badly, right? 

Now, I know the answer to that already, because I did tweak their recipes and still got jam.  Am I just being cocky because I had success?  With the peach strawberry, I was going for color (they were white peaches), and just did my best to guesstimate on sugar adjustments with subbing in one cup of mashed strawberries instead of one cup of mashed peaches (the sugar to fruit ratios were different for 100% peach vs. 100% strawberry, plus peach added lemon juice). 

I guess my questions are:  despite their warnings, how forgiving is making jam with Sure-Jell?  Did I just get lucky?  Are there any sort of guidelines to follow on how much a jam recipe can be tweaked? 

despite their warnings, how forgiving is making jam with Sure-Jell?  Did I just get lucky?  Are there any sort of guidelines to follow on how much a jam recipe can be tweaked? 

Despite the natural variation you mentioned, the volume of sugar in the Sure Jell overwhelms the variation.  In my experience, you need to be pretty tight when you follow their recipes.  That said, the risk is that your jam won't jell and you will either end up with a syrup or just need to reboil with a bit more sugar.

Freezer jams are more foregiving and less sweet, but they don't have the same shelf life.

Ok, Anne here so some help with jammin. I have made hundreds of mason jars of jam of all kinds over the yers, my basement is full of them. In my opinion, toss the pectin, sure-jell additive junk, you don't need it.  You need one recipee book only, Blue Ball cooking book, comes in most stores that sell canning supplies.  Basically, you tkae your fruit, toss in sugar, the longer you cook, the more thick the jam will be when it cools. For jam you want to cook till the hot jam in the pot just hardly oozes off the spoon. You can also stick some on a plate and place in the fridge for 5-10 minutes to cool to see what it will end up like. You do need to add sugar but I find you can cut back some, you ust may have to cook longer.  I hate the sure-jell idea becasue you take you nice fresh fruit picked from the garden and then add the additive to it that you don't need. Oh well, that is my advice.

can you re-can jam ?

I have and will have a bunch of different jams canned in pints and I was thinking of making a sampler variety pack in the cute 4 oz jars for Xmas gifts and stuff if I could just fill with jam and water bath process for 5-10 min.