How to Select a Good Onion

Start by choosing the best onions available. They will last longer and provide the best flavor. A good onion should feel firm, like a baseball, with a tight papery outer layer. Avoid onions with loose skins or those that feel soft. Also, check for weight; a heavier onion is preferable, as lighter ones have started to dehydrate and won’t taste as good. Look for onions with dried-out stem ends, and avoid those with green sprouts or visible bruising, brown or black spots, and mold.

How to Tell If an Onion Has Gone Bad

Look for Signs of Spoilage

Onions are known for their strong smell, but bad onions will have an unmistakably foul odor, reminiscent of rot, compost, or sulfur. If your onion smells like garbage, it’s time to toss it. If you spot green or brown powdery mold, discard the onion entirely, as the spores can penetrate the bulb even if you remove the outer layers.

Examine for Mold

Onions with mold are unsafe to eat. Mold usually appears as green or black powdery or sticky patches on the outer layers. Cut onions may develop thin, white, threadlike spores. Always discard moldy onions, as cooking does not make them safe to eat.

Dealing with Brown Rings and Sprouts

Is It Safe to Eat Onions with Brown Layers?

Sometimes, onions might look and smell fine until you cut into them and find brown, mushy, or slimy rings. While these layers are unappetizing, they don’t mean the entire onion is spoiled. As long as there’s no strong rotting odor, you can safely remove the brown layers and use the rest of the onion.

Are Sprouted Onions Safe?

Green sprouts from the stem do not automatically render an onion unsafe. Green onions or scallions are simply young onion sprouts. However, a sprouting onion may become soft or brown inside. If it’s still firm and white, the onion and sprout are safe to eat. If not, cut away the sprout and place it in water to grow your own scallions in about a week.