A great cup of matcha is sweet and grassy, a complex mixture of flavors that are gentle but not muted. It’s a flavor unique enough to match its vibrant green color, two qualities that have made matcha very trendy. Today, you’ll find it on most coffee and tea shop menus, but you’ll also find plenty of inspiration online for making it at home. Sure, you’ll have to work with a whisk to make a traditional cup of matcha yourself, but it’s easy and you can customize it to taste just as good as the matcha from the coffee shops. How long can you keep that container of matcha on your counter before you should throw it out?

We asked a tea expert for some advice on the shelf life of matcha, and it turns out that it doesn’t really go rancid. It doesn’t spoil when it expires, it just loses its mojo. Elle Liu, founder of Theoró, explained that matcha won’t make you sick as it ages, but it does lose color and flavor. And while old matcha isn’t necessarily a health hazard, the quality of this tea actually hinges on freshness.

“Because it’s a fine powder, it’s super sensitive to air, light, and moisture. You’ll want to drink it as fresh as possible, definitely within a few months of opening,” Liu said. “There’s no upside to aging green tea, so unlike pu-erh or certain oolongs, matcha (like all green teas) is all about freshness.”

The best way to preserve the quality of matcha is to start out with a top-notch product. And Elle Liu pointed out a list of things to look for when you’re choosing your new favorite brand, starting with a quick glance at the “best by” date. “The best matcha is usually packaged in a small foil bag tucked inside a tin, often with an oxygen absorber. Honestly, try to avoid buying matcha that comes in any other type of packaging,” she said. “Good matcha should be vibrant in color, have a sweet, umami aroma, and whisk into a smooth, frothy cup.”

If you notice your matcha has been sitting out on the counter too long, or that it’s gone a little dull, don’t throw it out. It has uses beyond the cup. Use old matcha in baking for breads and muffins, and in savory dishes like pasta and hummus. “Just like last year’s green tea leaves can be used in dumpling fillings or cooking, matcha that’s past its peak drinking quality can still be great for culinary uses,” Liu said. “Its flavor may be slightly muted, but I personally think it’s totally okay to make matcha ice cream, or matcha pastries, like cookies or cakes.”