Typical costs: Having a contractor level and prepare the area then pour a concrete slab ranges from $1,000-$2,000 for a 10x20-feet; $4,000-$6,000 for 80x20-feet; and $5,000-$10,000 for 100x100-feet. Smaller projects cost more per square yard because of minimum travel, labor and equipment costs.
What makes yogurt - well, yogurt? The words live and active cultures refer to the living organisms, Lactobacillus bulgaricus and Streptococcus thermophilus, which convert pasteurized milk to yogurt during fermentation. Note that the milk is pasteurized before culturing to remove any harmful bacteria.
Essentially all yogurt starts with milk heated to 180F or higher and held for several (15-30) minutes before cooling to the target temperature for bacteria culture addition (108-112F) and then held at this temp for the culture to ferment the lactose in the milk and add the characteristic flavor of yogurt.