As an experiment, I used a scoop of Fage greek-style yogurt as the culture for my last batch of yogurt. The result was very surprising: an astoundingly thick and creamy yogurt! But it also had one other characteristic I'm not sure I like.
I really love a sour flavor to my yogurt, and this yogurt made with Fage lacked this lovely tartness completely. It was like thick, creamy...milk. As used to sour as I am, this just tasted weird to me.
Up until now, I'd used Dannon yogurt as my original culture (and then used a scoop from each batch as the seed for the next). The yogurt this made was perfectly sour - almost too sour.
The next time I was at the store, I compared packages of Dannon and Fage, and I found my answer. All yogurts are required to have L. bulgaricus and S. thermophilus, but the Dannon contained an extra bacteria called L. acidophilus. This is a particularly acid-loving bacteria, and I think this must be the primary bacteria responsible for that sour flavor.
By the way, everything I've read indicates that the yogurt used as culture should have little or no affect on the texture of the yogurt. Flavor and nutritional profile, yes, but the texture comes from your process. This is why I was so surprised that the creamy and thick Fage culture made a creamy and thick homemade yogurt. Granted, my yogurt was somewhat looser than the original Fage, but the similarities were still incredible.
Honestly, I did this experiment not expecting the culture to make any difference at all. I wonder if the L. acidophilus causes the milk proteins to coagulate differently? In my next experiment, I'll try inoculating the milk with half Fage and half Dannon to see if it's possible to get the best of both worlds.
Any thoughts about what's going on there? What do you use to culture your homemade yogurt?
(Image: Emma Christensen)