Do You Actually Need to Use Almond Milk Within 7-10 Days?

We’ve all been there: You open up the fridge and grab your carton of almond milk, ready to make a smoothie, when you realize you’re not exactly sure how long it’s been open. You twist off the cap, give it a whiff and it passes the sniff test—nothing seems amiss, so it’s probably OK to drink, right?

Labels on most almond milk and other alternative milks, such as soy, oat and cashew, advise consuming the product within 7-10 days of opening. But in many cases, the product seems to actually look, smell and taste fine beyond that, so what gives?

“The 7-10-day recommended shelf life is based on optimal conditions. We know alternative milks can last this long even if they are not maintained under the most ideal conditions,” says Paul Neumann, vice president of research and development for Califia Farms almond milk. Those optimal conditions include consistent refrigeration and keeping the lid on tight—and under those, the refrigerated shelf life of an alternative milk after opening can be considerably longer than 7-10 days, Neumann says. (By comparison, dairy milk lasts about 7 days beyond its “best by” date if stored properly, below 40 degrees.)

So how exactly does it last longer? In some cases, it’s because it has added preservatives. (Ever checked the ingredient label of your alternative milk? You might be surprised to discover there’s a lot more in there than nuts and water). For alternative milks made with preservatives and stabilizers, such as gums or ascorbic acid, the shelf life can exceed 10 days. If you’ve ever noticed certain brands of alternative milks in the non-refrigerated aisle, that’s because they’ve undergone a pasteurizing procedure via ultra-high temperature and have been packaged in special Tetra Pak packaging to help them be shelf stable, says Sonia Ortiz, marketing director at Malk Organics plant-based milks.

While making products that last longer is a good thing for brands and for supermarkets, it’s not necessarily great for your health. Some preservatives and additives may upset your stomach, causing you to feel bloated and constipated (or the opposite effect), even though they’ve been approved by the FDA for being generally recognized as safe (or GRAS) for consumption, says Brigitte Zeitlin, registered dietitian and owner of BZ Nutrition.

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The FDA does not require date labels on foods, with the exception of infant formula. However, some state and local agencies may require expiration dates on certain kinds of food labels. Ortiz says many alternative milk brands will say “consume within 7-10 days upon opening” because it’s the standard disclaimer for perishable products. A spokesperson for Ripple says the company guarantees its plant-based milks as safe for consumption between 7-10 days of opening, but not beyond that for safety reasons due to potential variables in the environment in which the product is kept.

Taste and quality begin to degrade the longer any product is open, including alternative milks. “If the product looks, smells and tastes normal after 7 to 10 days in the fridge, it should be fine—you just need to use your good judgement and be on the lookout for signs of spoilage, especially as a bottle gets closer to empty,” says Neumann. One thing to keep in mind, he adds, is that the more times a package is opened, the greater the chance it will spoil. Plant-based milks can also pick up flavors and smells from other foods in your refrigerator pretty easily, giving them a less-than-desirable flavor (no one wants to drink milk that tastes like leftovers).

If you make your own almond milk from scratch, it will have a much shorter shelf life than the manufactured kind—only about three days in the refrigerator, says Ortiz. It might also be gentler on your stomach, if you’re sensitive to preservatives and thickeners found in store-bought milk. But in general, you shouldn’t worry too much about that occasional almond milk latte. “I think the closer to the whole, natural food you can get the better, so making your own with water and almonds would be the cleanest version,” says Zeitlin. “But if we’re being real, most of us are too busy to bother with that, and that is A-OK.”