Purpose of the Circular Dent on Milk Jugs

odd little circle in your milk jug is actually a flexible pressure zone. As milk gets colder or warmer during transport and storage, it expands and contracts. Instead of the jug bulging, cracking, or even bursting, that dent is designed to flex outward and inward, absorbing the stress. When jugs are dropped or slammed around in transit, the same shape continue reading …