It should set, but it will be very bland, perhaps tart, even. I am diabetic. I use Splenda and also unsweetened frozen apple juice concentrate. I use Pomona's pectin.
The apple juice adds some sweetness, but also a more rich tasting jam or jelly.

As mentioned, you can use no Splenda, but it will definately be bland. To help improve flavor, try addding a frozen concentrate (undiluted) like 100% grape or 100% apple juice. These still have natural sugar. If you find a decent tasting combo for a sugarless jelly, I suggest that you also try the Pomona pectin. Unlike the ones you see, Pomona will make up to 30 cups from one box, compared to 5-7 cups of no/low sugar types. Can you use a bit of honey as a sweetener? I too, use the same as Linda Lou, and even add a bit more acid blend to help keep them from spoiling once opened.

How much acid blend do you add to a pint of jam?

Where do you all find the Pomona's pectin? I looked today in the grocery store but didn't see it. Does Walmart carry that?

Pomona is hard to fine innstores, most natur food staores carry it, or you can find it on many web sites too. As to the acid blend (33% each of citric, malid, and tarteric), only about an 1/8 teaspoon is needed for a sinhgle pint of jam, but thats the minimal amout. I like a bit more tartness and can do up to about 1/4 teaspoon, but betind that its really sour, depending on how sweet it was to begin with! The cost for a 1 ouunc box of Pomona is about $4.39, or a little less if you can find it one sale somewhere. I found it last year at Frankferd Foods and it was a special sale for $3.69 a box. Right now, they sell it as $4.04 a box. Its made in Massachusetts, and is derived from citrus.

Here is a link that might be useful: Acid blend

Pomona is only available on line here where I live too.

Dad used to like Equal in his jam, he said Splenda left an aftertaste. Of course he wanted everything so sweet that my teeth would ache just thinking about it.

As mentioned, I like to add some white grape juice or apple juice to some fruit jams, and I also add other flavorings, like a bit of almond extract to cherry jam and cinnamon and nutmeg are good for apple. Cointreau is good with blueberries and ginger goes well with apricots.

I find that the full fruit jams mostly taste like sugar, not much fruit at all, but some of the all fruit jams need some help too. I taste test mine and then add sweetener but I seldom added more than a cup or two of sweetener to jam or it was just too sweet.

Somehow or another, it seemed to get sweeter when it cooled too, but maybe that's just me.

I just made a nice batch of sugar free apricot jam, and I added the zest and juice of one lemon, but no commercial pectin. I got a very nice lemon/apricot marmalade that set up well, but it was not what I was planning to make at all, I was trying for apricot jam, so be judicious about adding flavor components. (grin)

Annie

Thank you!

I also find an after taste with Splenda, thats the main reason I add the acid blend as it seems to lessen that.