Let’s be honest — you’ve stared at it.
You’ve poured your cereal.
You’ve twisted the cap.
And in that quiet moment before breakfast begins…
You’ve looked down at the side of the milk jug and wondered:
“Why is there a perfect circle… dented into the plastic?”
It’s not random.
It’s not a flaw.
It’s not leftover from the factory floor.
That little sunken circle?
It’s brilliant engineering.
And it’s doing way more than just looking mysterious.
Let’s dive into the surprisingly smart reasons behind the circular dent on your milk jug — and why this humble design feature is quietly protecting your breakfast, your kitchen floor, and even your health.
🧪 1. Pressure Relief – A Built-In Safety Valve
Milk isn’t just a drink.
It’s a temperature-sensitive liquid that expands when warm and contracts when cold.
During transport:
