When most people think of yogurt, they think of thermophilic yogurt. This is the generally the yogurt you will find in the store or supermarket. Mesophilic yogurt is a yogurt that is fermented at room temperature (65-80 degrees) vs 115 degrees for thermophilic yogurt. That is why it is considered a ‘room temperature yogurt’.
All cultures have an amazing ability to adapt to their environment. Milk kefir naturally does very well in the colder months, but the other cultures can adapt quite well as well. Surprisingly, the cold is not the biggest obstacle to good fermentation, but rather its the fluctuation of temperatures.