On Sunday, I worked my way through preserving the peck of peaches that I had picked up at a local orchard. Since peach jam is one of my favorite flavors, that was definitely on the list.
Generally speaking, when I make jam, I use the old fashioned "boil-down" method as opposed to using commercial pectin. This process takes advantage of the fruit's natural pectin to produce the gelled "set" you expect from good jam and you can often get away with much less sugar. It makes for a richer cooked fruit taste and is a bit on the soft spreadable side.
In the case of peach jam, I've used commercial pectin in the past and I really like the results. The peach chunks keep their vibrant orange color and the yield is much higher because you don't have to boil it down to mush. However, the volumetric sugar-to-fruit ratio for commercial pectin recipes is usually almost 1:1 or sometimes even more sugar than fruit. That's a bit much, if you ask me. You end-up with a product that's candy-sweet and guaranteed to make your blood sugar soar and then plummet.
Since every recipe for commercial pectin jams warns that altering the delicate sugar balance might cause the jam not to set, I turned to a "less sugar needed" version of Sure-Jell's flagship pectin product (in the pink box). From what I can tell, they've added some acid to the pectin packet and tinkered with the recipes a bit to be able to use at least 25% less sugar. I wasn't quite sure how this would work out but I went into it with my fingers crossed, hoping I wouldn't ruin my beautiful fruit.
I can only say that it's a fantastic product. Instead of nearly 6 cups of sugar, the recipe called for just over 4 cups and the resulting product is even better than the original. It set-up just fine, had a bright peach flavor, and wasn't candy-sweet like last year's batch.
I highly recommend using "less sugar needed" pectin if you're making jam.