Why aren’t plastic milk jugs sealed (also some teas, drinks, etc) AKA why does the milk always leak?


Foil, plastic, foam-type things are on the orange juice and the coffee creamer and the Tylenol, etc. Why not on milk jugs?

I thought maybe heat issues, but it’s already undergone multiple heat treatments. Also thought maybe cause the product is so quickly meant to use, not worth the time. Then I thought, the attempt to make containers as thin as possible, and general motion would crack seal.

In: Technology

Milk jugs don’t have foil seals because milk has a relatively short shelf life even if the container is sealed. All the products you used as comparatives have much longer er shelf lives.

Hmm… all the milk jugs I’ve bought here so far (UK) have foil seals. So it’s surely possible and has helped prevent quits a few spills. Those screw tops come off by accident way too easily.

I should have stated, US based. I’m all about the other options I’ve seen in travels – bagged, always waxed carton with plastic seal, etc. But this is totally the ubiquitous US plastic jug – and it comes in all the half/pints/quarts/gallons.
I demonstrated my confusion the other day when I ensured hand-tight, unopen gallon … Then squeezed it. Sure enough, milk came out. To confirm it wasn’t an expansion thing, viscosity, bubbly-shaky – I grabbed a gallon tea that I knew wasn’t sold with seal, then a lemonade. Same results.