Condensed milk is concentrated milk + sugar, after dilution is also very sweet, sweetness is appropriate after the concentration of milk is very low, so it is not recommended to use diluted condensed milk to make yogurt, because out of it will not be good to drink, and low concentration of milk made of yogurt is prone to spoilage.
Condensed milk yogurt may be higher than the cost of using fresh milk, condensed milk concentration ratio is about 40% of the original volume, that is, 2 two condensed milk to make half a kilogram of yogurt, which is not as cheap as half a kilogram of milk directly.