Why does regular milk take only a week or two to expire, while my iced coffee containing milk doesn’t expire for months?

Question

I’m specifically drinking Dunkin Donuts bottled iced coffee. It says it contains skim milk in the ingredients list.

In: Chemistry

Answer 1

Although I’m not familiar with the brand ingredients, it’s entirely possible that the milk in your iced coffee has gone through the ultra-high temperature (UHT) process to increase the longevity of the product.

This process sterilises liquid by heating to 275F, killing bacteria endospores which otherwise would spoil the milk sooner. Milk treated in this way will have a shelf life of 6-9 months and can be left unrefrigerated.