Milk in NYC

[debka_notion]

I just tried to make myself a nice cup of tea with milk in it before bed, and when I poured the milk in, it was chunky. This is 4 days before the sell by date in NYC- whereas the milk I bought in Boston usually lasted quite a good while beyond that date, when I didn't use it up too fast, except once in the summer.

I don't understand New York City. Is there something about the place that causes milk to curdle?