Greek yogurt, renowned the world over for its quality, density, and unabashed, delicious sour taste is a product of the country’s pastoral traditions. Up until fairly recently, yogurt production was ruled entirely by farming and seasonal conditions. Sheep and goats provided most of the milk Greeks consumed. Yogurt was always made with sheep’s milk and was seasonal, produced from late fall to early June.
There were two reasons for the seasonal production. Sheep produce milk from the moment they lamb until the summer, when the heat and the shortness of plants to graze on naturally will condition them to dry up. The heat of a Greek summer was never ideal for dairy production. Yogurt needs to be kept cool once it is set, and until the 1950’s refrigeration was rare outside cities. The storage cellars, cool enough from fall to spring, loose their chill in the summer.
Yogurt was made immediately after the milking, when the temperature of the milk is the same as the animal’s and ideal for the addition of the lactic acid bacteria that turn it into yogurt. The shepherd would simply add a little yogurt from the last batch as starter to the fresh milk. He would keep the containers covered and warm, probably in the room where he made his cheese.