I love making my own yogurt. I use a Cuisinart machine these days since it has a built in fermentation timer and little cooling panel to refrigerate the batch when the timer is off.
I really want to use a non-sugar sweetener but my first attempts with stevia drops (no alcohol, in glycerin) completely killed two cultures. I know it was the stevia drops as I put a little unsweetened mix to the side and it came out perfect.
I've boiled my fruit extracts to reduce alcohol before adding, all kind of different things to make my bacteria happy despite all the crap I add to the batch.
My current favorite is to use powdered milk in with whole milk or alone to create a thick Greek style yogurt without straining and with that strong protein mesh that normally you would see if adding gelatin or agar to the recipe. (I.e., 1 pkg culture or 1/4 cup last batch yogurt, 3 capfuls alcohol free vanilla, 2 capfuls lemon extract boiled if a high alcohol content brand, 4 cups filtered water, 2 cups dried milk, 10 drops yellow food coloring, warm ferment for 8 hours no boiling.)
I'm currently starting with freeze dried starter from yogourmet as I can do several more serial batches than from store bought or friend's yogurt as starter.
Any ideas for a low cal sweetener that won't kill my wonderful little bacterial friends?