The Way To Tell If Your Mayonnaise Has Gone Bad

Though it may seem like mayonnaise is outshined by other condiments, it is actually very popular in the U.S. In fact, it has quite an interesting origin, a history of being a luxury food, and was the most popular condiment in the U.S. in 2021, per Statista. Mayo's versatility likely plays a role in its popularity. You can add it to a variety of dishes, ranging from mashed potatoes to chocolate cake (via Southern Living). However, you won't be able to take advantage of this versatile condiment if, of course, it spoils.

Like many other foods, mayonnaise can only sit in your refrigerator for so long before you have to throw it out. According to the USDA, mayo lasts for about 2 months after you open it. Even with this time range in mind, you might not be keeping track of how long your mayo has been in the refrigerator. Don't worry, there are some key ways to determine if your mayo has gone bad.

Look for mold growth, a color change, and a bad smell

Mold growth, a change in color, and an unpleasant smell are three indications that your mayo has gone bad. According to the Department of Health of New York State, molds can grow anywhere that moisture is present, which is why they can thrive in mayo. Certain molds are harmful to health, as they can potentially cause allergic reactions, respiratory issues, and other illnesses due to poisoning (via the USDA). Because of the health issues mold causes, it is a great indicator that your mayo has spoiled.

Furthermore, once mold begins to grow, it continues to reproduce through spores, per the USDA. Spores give mold its color and, thus, cause mayo to change from a creamy, white hue to a yellow or brown hue. So, a change in color is also an indication that your mayo has gone bad, as it results from mold and spore growth. Additionally, the USDA reports that spoiled foods typically have an unpleasant, pungent smell and taste. Therefore, if you notice that your mayo has a strong, acidic aroma or taste, it is likely spoiled.

What to do if your mayo is bad

So, let's say your mayo is spoiled: What should you do? If you notice any mold growth in your mayo jar, a change in color, or a pungent smell or taste, you should immediately throw the jar away, per CBC News. Moreover, foods with high levels of moisture cannot be saved after they spoil because mold growth occurs below the surface of the food. According to a 2020 study in the Research, Society, and Development Journal, mayo contains a high moisture content. So, this means if you see mold at the top of your mayo jar, it's likely spread throughout the entire jar, meaning you should definitely toss it.

According to the USDA, there are some things you can do to prevent mayo and other foods from going bad. A simple thing you can do is check your food before purchasing it. When looking for a jar of mayo at the store, examine the jar for any signs of spoilage and check the expiration date. Also, never leave mayo or any other perishable items unrefrigerated for more than two hours. If you follow these tips and keep an eye out for any indication that your mayo is bad, you should be able to enjoy the creamy deliciousness this condiment offers.