I frequently make yogurt at home, and I decided to try to make Shankgleesh, a spicy Middle Eastern cheese that is difficult for me to find at local markets. Several recipes said to heat the yogurt until the proteins coagulate and separate from the liquid. They should look like clumps or curds. Then the liquid is drained off and the curds strained for several days. When I heated the yogurt, it just got soupy. It never formed curds or separated. I simmered it for more than a half hour. There didn't seem to be anything difficult about the recipes. I wondered why I could not get it to work. The only thing that is unusual about my yogurt is that it is fermented for 24 hours so that the bacteria consume all of the lactose. Could this have affected the coagulation of the proteins? Thanks for any help.