Final answer:
The processing step that prevents chalky milk is homogenization. This process ensures a uniform texture by reducing the size of fat molecules, distinct from pasteurization or filtration.
Step-by-step explanation:
The processing step that helps prevent chalky milk is homogenization. Homogenization is a process that mechanically breaks down the fat molecules in milk to a smaller size, which prevents them from separating and rising to the top. This results in a uniform mixture and texture, avoiding the chalkiness that can occur in untreated milk. This process is different from pasteurization, which is the heating of milk to destroy harmful microorganisms, and Filtration, which involves removing particles from the milk. UHT (Ultra-High Temperature) pasteurization is an extended form of pasteurization that heats milk at very high temperatures and then seals it in airtight containers, which allows it to be stored for extended periods without refrigeration, but it's not primarily for preventing chalkiness.