Yogurt Making

I bought a yogurt maker online. You have to do all the heating of the milk and adding of bacteria, but the machine cooks the yogurt at a constant 111-115 degrees for bacteria growth. Javers, Willa (our temporary roommate) and I tried it out last week and it was mildly successful. The directions suggested cooking for 10 hours the first time. The longer you cook it the firmer and tarter it gets. I think 10 hours was too tart so we will shorten that the next time. Also, Javers heated up the milk too quickly and the instruction book said that can make poorer quality yogurt. He wouldn't eat it, but I added some sugar and fruit and I thought it tasted fine. Plus, it's something we made so that makes it exciting to eat. Handcrafting yogurt makes me feel somewhere inbetween a microbiologist and a French peasant.