In a consumer-focused world, it can be difficult to understand why manufacturers, suppliers, and grocers create products with little quirks.
Small things, for instance—like the difference between “chicken stock” and “chicken broth” or the “correct” way to make Kraft Mac & Cheese—can be lost on shoppers. When people eventually rediscover a different way to look at a product, it can feel like a revelation.
A man from Florida had a similar experience. Jack Finger (@willysfinger on TikTok) posted a video with more than 23,700 views in which he asked why milk jugs have a circular dent in them.
In Finger’s video, he holds up a jug of reduced-fat milk, which had an obvious dip on the side. Finger asks, “What is this? What is this for?”
Commenters tried to explain, and a few correctly guessed what the circular indent actually did. But others remained just as stumped as Finger was.
Common Myths And Theories
While a few commenters joked that the dip was the “reduced-fat” part of the jug, others gave their own explanations.
“It’s for your protection if that pops out, it means the milk is no good. They can’t talk to you. With their voice so they’re showing you on their milk to save you from drinking sour milk,” one commenter wrote.
This theory, however, is a popular myth about milk dents, which was popularized by a viral Facebook post that was later debunked by USA Today. In reality, the milk in any store-bought jug would have to be incredibly spoiled for the indent to pop out. Most spoiled milk doesn’t release gas to begin with. Experts in the industry have previously explained that it’s not the reason milk jugs are designed that way.
What Is The Circular Dent Actually For?
There’s a real reason manufacturers all leave a circular indent in milk jugs, at least according to Matt Herrick, executive vice president and chief impact officer of the International Dairy Foods Association, who was interviewed by science reporter Lisa Lombardi for Reader’s Digest.
When milk travels from supplier to grocery store, it ends up in varying different refrigerators. A jug of milk might end up on a refrigerated truck that has a slightly different temperature than a grocery store, for instance. As it moves, the temperature changes, which can make the liquid inside expand or contract. The dent, then, helps maintain the bottle as the milk expands and contracts due to those temperature changes.
Mike McCarty, the vice president and sales manager of Indiana Bottle Co., told USA Today that the design also helps improve cost efficiency. In addition, the dent can make the plastic bottle more flexible and therefore less likely to break when dropped or dented during transit.
Commenters Weigh In
Regardless of the indentation’s purpose, commenters made alternative suggestions that fully take advantage of the circular quirk.
“Ranch sauce holder,” wrote one viewer.
Another commenter joked, “Death Star milk,” referencing “Star Wars.”
BroBible reached out to Finger via TikTok direct message and comment.