There are few things more disappointing than realizing that the gallon of milk in your fridge is about to expire, and you've only taken three or four sips of it. But instead of letting that perfectly good milk good to waste, you can actually freeze milk and save it for later. According to Marianne H. Gravely, senior technical information specialist at the US Department of Agriculture, "There is no safety problem with freezing milk, and it tastes pretty much the same after being frozen." She does add that frozen milk "will taste best if used within three months," but as far as food safety is concerned? The frozen milk "will be safe indefinitely," as long as you store it correctly.
So how do you freeze milk safely? As Laura Northrup writes for Consumerist, you can freeze a whole gallon at a time, though notes that it the jug shouldn't be filled to the top. The experts at the Dairy Council of California second that warning, adding, "Milk will expand when it's frozen, so be sure to leave room in the container so it won't burst!"
You can also pour milk into smaller containers, rather than freeze a jug of milk at a time; that'll make both freezing and thawing easier. Some folks even pour milk into ice cube trays to freeze; it's a great way to keep an iced coffee or iced tea cool without watering it down.
Frozen milk isn't a perfect solution, however. For instance, according to British newspaper The Telegraph, frozen milk might take on a yellowed hue, especially if it's whole fat. You also need to plan ahead before you use your frozen milk, because the safest way of thawing milk is also the slowest. When you're thawing frozen milk, you don't want to just leave it on the counter at room temperature or toss it into a bowl of hot water. According to the USDA, perishable items like milk must be kept at a safe temperature while thawing because, "as soon as they begin to thaw and become warmer than 40 °F, bacteria that may have been present before freezing can begin to multiply" and those will make you sick.
Instead, you want to take your frozen milk out of the freezer and into the fridge, at least 24 hours before you plan on using it. And be sure to shake up your once-frozen milk before drinking, so that all the different bits can recombine. The texture and taste of the milk might be a little different than it would be if it's fresh from the farm, but it's still safe to drink. So go ahead, and freeze, baby, freeze, and never run out of milk again.