How to Tell if Mayonnaise has Gone Bad? And Methods to Store it

Does Mayonnaise Go Bad
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Mayonnaise is a creamy dressing that is added to salads, sandwiches, and burgers to make them more indulgent. Mayonnaise is made of a combination of egg yolk, lemon juice, vinegar, oil, and herbs. For the vegans, there is vegetarian mayonnaise available. But the most common concern about mayonnaise is, does mayonnaise go bad? Also, does mayonnaise expire?

Yes, mayonnaise does spoil, but you can extend its shelf life. Read on to know the facts about mayonnaise.

How Does Mayonnaise Go Bad?

We always see mayonnaise jars stored at room temperature at the grocery stores. So, can mayonnaise go bad if the jar is unopened? No, it doesn’t, because the jar is sealed tightly and hasn’t been opened yet.

An opened jar of mayonnaise can go bad depending on how it’s made. It can be homemade or commercial. Homemade mayonnaise can go bad more quickly than commercial mayo as it is made from raw eggs.

Commercial mayo contains pasteurized eggs, and so it has a longer shelf life. It can be refrigerated and will last for up to two months after opening.

Mayonnaise, whether homemade or commercial, goes bad if it contains bacteria such as salmonella, which can happen by inserting a contaminated knife or spoon into the jar. Breadcrumbs and fish like tuna or salmon, all carry bacteria which may contaminate the mayonnaise if you dip a piece of bread or fish in the mayonnaise jar.

You should avoid cross contamination of mayonnaise. Often, the food prepared with mayonnaise with goes bad. For example, the bread from a sandwich can perish, but the mayonnaise inside may not.

A sandwich, burger, or any other food product that contains mayonnaise should be consumed in an hour. Upon refrigeration, the food can last for up to a week.

How to Tell if Mayonnaise is Bad?

Mayonnaise can go bad once exposed to high temperatures after opening or due to contamination. You can use your sense of smell and taste to decide if the product is bad.

Here are few signs of a bad mayonnaise:

  • A change in color to brown or a darker shade of white
  • Appearance of mold
  • A foul smell
  • A change in texture with the formation of clumps

All these signs indicate that the mayonnaise is no longer safe to consume. Mayonnaise can go bad, but you should know how to extend its shelf life. You should always check the packaging label for the mayonnaise best by date or expiration date before buying it.

How Long is Mayonnaise Good for after Expiry Date?

It is safe to consume mayonnaise can after the expiry date, but you will notice a change in the quality. The color may have slightly changed, but you can safely consume if it was refrigerated.

Let’s look at the differences in expiration between commercial and homemade mayonnaise.

Commercial Mayonnaise

1. Unopened jar at room temperature

Mayonnaise can be stored at room temperature if the jar isn’t open, and you can keep it in the cabinet or pantry until the use by date. You can still consume it up to a week after the use by date. But, it should be discarded and not consumed beyond that.

2. Unopened and refrigerated

University studies, government experts, and other reliable food safety sources such as conclude that you can safely consume unopened mayonnaise for a month after its expiration date.

3. Opened and refrigerated

An opened jar of mayonnaise, if refrigerated, will keep the mayonnaise safe to consume until a month.

Homemade Mayonnaise

Homemade mayonnaise has more eggs than the commercial varieties. It can keep up to two weeks if refrigerated. If it is not refrigerated, it will perish within a few hours.

How to Store Mayonnaise?

Storing mayonnaise depends on whether it is homemade or store-bought. Store-bought mayonnaise contains pasteurized eggs, which prevents it from going bad even if it’s not refrigerated. It also contains lemon juice and vinegar which prevents the growth of bacteria.

Not refrigerating an unopened jar of commercial mayonnaise hampers the quality but doesn’t spoil it. Experts recommend keeping mayo at a temperature of 4.44°C.

How Long Does Mayonnaise Last?

Homemade mayonnaise doesn’t have enough acid or salt for preservation. It should be refrigerated to maintain its quality and prevent bacterial growth.

Homemade mayo can be refrigerated up to five days only. Commercial mayonnaise can last for two months, if refrigerated.

In conclusion, mayonnaise does go bad, but you can increase its shelf life by handling it more carefully and storing it at a proper temperature.



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