Yogurt Culture Recipe:
To make your own culture purchase one pint of plain yogurt. Add one cup to a Quart of milk in a mason jar with a lid. Let sit for 8- 12 hours in a warm place such as near a wood stove or radiator. Ideal temperature is around 100 degrees.
Careful not to get too hot or stay too long.
A crockpot or slow cooker on the lowest setting with a towel under it may do the trick.
You can add your own fresh, canned or frozen fruit to taste.