I hate to heat-treat our raw organic homegrown milk under any circumstance...But for some reason, despite keeping the yogurt at 110 degrees, it never thickens... Heating it to 170 then cooling/keeping at 110 works every time... Anyone have any special tricks??
Typical instructions for making yogurt indicate that the initial heating is to inactivate organisms that would interfere with the activity of the yogurt making bacteria. This may be why your yogurt is not 'yogging.' At one point I was getting raw goat's milk to make yogurt, and had the same issue. My solution was to add agar agar, which gave me a smooth yogurt consistency while the starter (I assume) incubated enough to give me the live cultures I wanted. When you look at the history of yogurt making, it certainly was made with raw milk, of what? mares? Certainly not subject to American law!