Does Almond Milk Go Bad?

If you, like me, are nut-milk curious, then you’ve probably tried almond milk at some point. Maybe you add it to coffee or blend it with fruit into a creamy smoothie. You might even use it as a dairy-free alternative in baking. And if you, like me, have found that half-empty, mostly-forgotten container of almond milk in the fridge and can’t remember why you bought it, you’ve probably wondered if it’s gone bad.

Almond milk won’t develop a sour smell exactly like cow’s milk does when it starts to turn. But there are some telltale signs you can use to determine whether your almond milk is destined for another batch of banana bread, or if you should pour it straight down the drain. We talked to a couple of food safety experts to understand exactly how long you can hang on to that carton, whether refrigerated or shelf-stable and opened or unopened.

How to tell if almond milk has gone bad:

There are at least four culprits to consider when good almond milk goes bad: bacteria, oxidation, yeast, or mold. Any of these can be unpleasant, but some are worse than others. The best way to tell if you’ve got expired almond milk on your hands is through sensory investigation. “You’ll notice off flavors, off odors, and it may become a darker color,” explains Kimberly Baker, Food Systems and Safety Program team director at Clemson University. Give the milk a sniff and let your nose tell you how to feel. Stale odors, like wet cardboard or paint thinner, may indicate your almond milk has gone rancid (thanks, oxidation). If you’re unsure, Baker says it’s okay to give it a small sip; if it has a sour taste or is otherwise unpleasant to drink, you know what to do.

The consistency of your almond milk can also be an indicator of spoilage. The introduction of bacteria or yeast (think fermentation) can cause the milk to thicken or curdle. But clumping solids don’t always mean your almond milk is unsafe to use. Some separation in almond milk is natural, notes Baker. It’s good practice to shake any milk alternative before opening to re-emulsify anything that’s settled to the bottom. But, if it starts to separate immediately when you pour it out (or, worse: if it stays chunky), toss it. If your almond milk has really gone south, black mold can start forming on the surface and inside the container—if you see signs of spoilage of this kind, don’t take any chances.

Can you drink almond milk past its expiration date?

If you live and die by the numbers stamped onto your food, you can loosen up a bit. While these numbers are largely arbitrary, they can provide a gauge, if not a rule. “Usually almond milk will have a ‘use by’ or ‘sell by’ date,” Baker says. “A sell-by date means there’s an extension of good quality beyond that date; a consumer can know they have five to seven days to consume or freeze the product.” An expiration date “is more final” when it comes to that extension of quality, but even if your almond milk is past its expiration date, that doesn’t necessarily mean it’s gone bad. How the item was shipped and handled in-store, how often you open your fridge, how many times a day you pour yourself a big cup of almond milk, and other factors will also affect its shelf life, so take any “___ by” date with a grain of salt.