Kristie Leong M.D. is a family practitioner who believes in the power of nutrition and a healthy lifestyle to prevent and fight illness.
Collard greens are a green leafy vegetable that you can enjoy in soups, stews, salads, or as a side dish. They are an excellent source of vitamins A, K, and C, and some B vitamins, particularly folic acid. They also contain calcium, iron, magnesium, and potassium.
As versatile as they are, collard greens don’t have an unlimited shelf life. What if a batch of collard greens has turned yellow? You might wonder whether they’re safe to eat or whether you should discard them.
Yellowing of Collard Greens Is a Sign of Aging
When collard greens age, their vibrant green leaves can turn a dingy yellow.
Why does this happen? All green vegetables contain chlorophyll, which gives them their green coloration. Over time, the chlorophyll in collard greens breaks down. As it does, the leaves lose their rich green shades and become more yellow.
However, this color change doesn’t mean yellowing collard greens are unsafe to eat.
They May Have a Different Flavor
Although edible, yellow collard greens may not have the same taste as younger, greener ones. With age, they lose some of their flavors and may even become bitter. So, you may not enjoy eating yellow collard greens as much.
If you have yellowing collard greens, take extra effort in preparing them and serve them with a sauce that makes up for their loss of flavor.
As collard greens age, they also lose some of their nutritional value. Vitamins that are most sensitive to light, heat, and age include some B vitamins, like thiamine, and vitamin C. So, collard greens with yellowing may be less nutritious—but they still retain their minerals. Age also doesn’t affect their fiber content.
How to Prevent Collard Greens From Turning Yellow
Since the yellowing of collard greens comes from chlorophyll breaking down due to aging, you can’t completely prevent it. However, storing collard greens properly will reduce yellowing and keep collard leaves green longer.
When you buy these greens, don’t wash them before storing them. The water can cause them to rot prematurely. Place them in a sealed plastic bag with damp paper towels to keep them from drying out. The best spot in the fridge for collard greens is the vegetable crisper. Collard greens will last in the refrigerator for around four days.
Watch for Signs That They're Going Bad
Although most yellowing is just a sign of age, inspect collard greens closely before eating them. If you observe any of the following signs, the leaves may be infected with a fungus or rotting, and you should throw them away.
- They feel moist or sticky
- They smell bad
- They have black- or orange-colored spots on them
If you find your collard greens turn yellow too quickly, freeze them to keep them fresh longer.
How to Freeze Collard Greens
Method 1 (No Blanching)
- Before freezing, wash the greens and remove the stems.
- Transfer the frozen greens to freezer bags or containers with as little air as possible.
- Label and date each bag so you know when you made it.
- Use within three months for best quality.
Method 2 (With Blanching)
You can also blanch collard greens before freezing them. Blanching involves boiling the vegetables in water for a few minutes before freezing them. This step helps lock in nutrients and retain flavor, but requires more work.
You will need to blanch the collard greens for about two minutes before placing them in an ice bath to cool down quickly. After cooling down, pat dry with a paper towel and place them in a freezer bag or container until you’re ready to use them.
Yellow collard greens are still edible as long as they show no signs of rotting, and you can still cook them in a way that makes them more enjoyable. These leafy greens are one of the most versatile and nutritious greens you can eat, and they’re worth keeping around.
If you find yourself with a yellowing bunch of collards, don’t toss them! Just follow these tips for keeping your collards green, and don't be afraid to experiment with cooking methods. Try them steamed with garlic or sauteed with olive oil or butter. You can also make collard green soup by simmering them with chicken or vegetable broth. Enjoy!
- "Collard Greens: Nutrition, Benefits, Recipe, and More - Healthline." 11 Aug. 2021, https://www.healthline.com/nutrition/collard-greens-benefits.
- "Collards, raw nutrition facts and analysis.." https://www.nutritionvalue.org/Collards%2C_raw_nutritional_value.html.
- "Lettuce, Other Leafy Greens, and Food Safety | CDC." https://www.cdc.gov/foodsafety/communication/leafy-greens.html.
This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.