1 ordinary fermented yogurt base strain is mostly Lactobacillus bulgaricus and Streptococcus thermophilus, charcoal-fired yogurt is Lactobacillus casei.2 Ordinary fermented yogurt is 90 degrees for 5 minutes of sterilization conditions. Charcoal-fired yogurt sterilized at high temperatures or for a long time, a few hours, in the sterilization process produced a Melad reaction, white milk from the color of the browning, the flavor also changed, produced some caramel flavor and other flavors, so that the yogurt taste richer and more intense.