States have different standards, and they range from 3 to 3.8 percent milk fat. If the milk fat percentage is too high, dairies add skim milk. If it's too low, they add cream to meet the standard. Milk must also be clarified before it's bottled. This process removes any sediment or foreign material from the milk by centrifugal force.
Milk is now ready to be pasteurized.
The HTST equipment is very sensitive and precise and uses valves and small tubes to route the milk. Some older plants may still use the batch process to pasteurize their milk. The batch process heats milk to 143 degrees F for 30 mintues. Vacuum equipment has also been installed with the latest pasteurization units to remove any gases which might give milk an off-fiavor. Milk is now ready to be homogenized, a process which reduces milk fat globules from a size of 5 microns down to 2 microns or less.