Can You Eat Sprouted Onions? Food Safety Experts Weigh In

It's easy to buy essential ingredients like onions in bulk so you always have them on hand for last-minute recipes. But sometimes, that bag of onions can go untouched for days, and even weeks, leading to a bright green shoot poking out of the top of it. Sound familiar?

Sprouted onions are a common kitchen surprise, and they often raise the question of food safety. To clear up the confusion, we spoke to food safety experts to learn what sprouting really means, whether it affects safety or nutrition, how to tell when it is still good to eat, or when it's best to toss it.

Why Do Onions Sprout?

You've probably come across a sprouted onion bulb on your kitchen countertop from time to time—and it's completely normal. Sprouting occurs when these vegetables are exposed to conditions that promote new growth, such as light, warmth, and moisture, which often happens during kitchen storage.

Are Sprouted Onions Safe to Eat?

Preventing food waste is always important, but it's even more crucial to know what’s safe to eat. If you bought too many onions a few weeks ago and notice a few sprouts have grown, that's okay; they are still safe to eat as long as the onion has not spoiled, according to the U.S. Food and Drug Administration.

However, it's best to use the sprouted onion sooner rather than later, before the flavor changes further. Sprouting is a natural process for onions that does not produce harmful compounds. Unlike potatoes, sprouted onions do not become toxic or increase the risk of foodborne illness, as Shannon Stover, food safety educator at Michigan State University Extension, explains. Still, as with all produce, sprouted onions should be rinsed under cool running water before preparing to eliminate any pathogens that could cause illness, Kimberly Baker, food systems and safety program team director at Clemson University Cooperative Extension, advises.

As the sprout grows, it uses nutrients from the bulb, which can make the onion’s flesh softer and slightly more bitter over time, affecting the flavor of your dishes, notes Baker.

If there is no spoilage, pregnant individuals, older adults, young children, and immunocompromised persons are not at greater risk from eating sprouted onions. 

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Can You Eat the Green Sprout?

You may wonder: Is it safe to eat the green sprout on an onion? Yes, it is. The green sprout is safe to eat, but the flavor is often stronger, more pungent, and even sometimes more bitter compared with the bulb, says Baker.

If you prefer a bolder taste, chop the sprout and use it in dishes such as chili or taco meat, Stover suggests. Keep in mind that the texture is firmer and more fibrous than the rest of the onion.

When to Throw a Sprouted Onion Away

As long as the bulb remains firm and free of rot or mold, you don't need to throw the onion away. However, discard it if you notice dark or fuzzy patches, a slimy or overly soft texture, wet or leaking layers, a strong, unpleasant odor, off-color flesh, visible decomposition, or signs of pests in your kitchen. "These changes signal deterioration and potential microbial growth, making the onion unsafe to eat," Baker warns.