It's also not entirely lactose free. Ask me how I know.

Cries in lactose intolerance

It doesn't taste the same. The lactase breaks the less sweet lactose into glucose and galactose, which are about twice as sweet as lactose (all are less sweet than table sugar.)

Also lactose free milk is typically ultra pasteurized, which gives it the longer shelf life, but ultra pasteurization does impact taste. It gives it a "cooked" flavor.

Lactose-free milk is much sweeter than regular milk and expires in the same amount of time unless you're buying the long life version.

Is your lactose free milk prepared/packaged differently from your regular milk? The two keep for just as long here.

Tip: Oat milk is yummier.