How Long Does Mayo Last?

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Many appreciate the taste of mayonnaise, however, only a handful know the procedure of preparing it.

It’s easy to find in supermarkets and restaurants alike, but there are plenty of recipes out there on sites like Pinterest for homemade versions.

If you’re looking to try your hand at making mayo, or want to learn more about the condiment itself, you’ll be glad to know that it’s not as difficult as you might think.

The main ingredient in mayo is oil (typically vegetable oil) and eggs.

This makes it a solid product, which means it won’t spoil easily.

But that doesn’t mean that it’s indestructible.

Mayonnaise will eventually go rancid, just like any other edible product.

The time it takes for this to happen depends on a number of factors, including where you store it, how much light it gets, and what kind of bacteria are present in its environment.

In this article, we’ll explain why mayo spoils, how long it lasts once it has spoiled, what you can do with old mayo, and when it’s safe to use leftover mayo again.


Does mayo go bad?

Yes, mayonnaise does go bad.

In fact, it goes bad faster than most other foods.

That’s because it contains an acid called acetic acid, which is known to cause food to decay quickly.

While this isn’t necessarily true of all types of mayonnaise, it’s certainly true of commercial brands that contain vinegar.

This is one reason why you should always keep your mayonnaise in the fridge.

At best, it will only spoil quickly, rather than becoming moldy or rotten.

You can also extend the shelf life of your mayo by storing it in the freezer.

Just make sure that you don’t freeze it solid, since ice crystals can damage the texture of your mayo.

How Long Does Mayo Last? 1

How long does mayo last?

Just like many other foods, mayonnaise is perishable.

This means that it will eventually spoil.

However, it’s important to note that this is not a matter of days or weeks.

Rather, it’s a matter of months or years.

There are several reasons why mayonnaise can spoil.

For starters, it’s made from raw egg, which are susceptible to salmonella, a type of bacteria that can cause illness.

Salmonella is particularly harmful to children, pregnant women, and anyone who is immunocompromised.

Another factor that affects the shelf life of mayonnaise is temperature.

As mentioned above, the acid in mayonnaise causes it to spoil much faster than other foods.

If you keep your mayonnaise in a warm place, it will spoil sooner.

On the other hand, if you keep it in the refrigerator, it will spoil slower.

This is another reason why you should always keep your mayonnaise in the fridge.

However, even if you take care to protect your mayonnaise from heat and humidity, it’s still possible for it to spoil.

This is due to the presence of bacteria that thrive in these conditions.

These include listeria monocytogenes, E. coli, and salmonella.

These bacteria can contaminate your mayonnaise through three different ways:

  • From the air
  • From the water
  • Through contact with other foods

It’s important to note that some of these bacteria can survive cooking temperatures, which means they could potentially be transferred to your mayonnaise during the process.

What is the shelf life of mayo?

The shelf life of mayonnaise varies depending on the brand and how it was processed.

Some brands have a longer shelf life than others.

Generally speaking, however, you can expect to eat mayonnaise for up to two years after it’s been opened.

If you’ve purchased a fresh batch of mayonnaise, it will likely have a shelf life of around six months.

This means that it will start to lose its flavor and smell within that period of time.

Once it starts to deteriorate, it’s best to throw it away.

How can you tell if mayo has gone bad?

You can tell if your mayonnaise has spoiled by looking at the color and consistency.

If it looks dark or grainy, it’s probably past its prime.

It should appear translucent, and you shouldn’t see any visible signs of mold.

If you’d like to test your mayonnaise before buying a new bottle, you can do so using a pH meter.

Simply dip a small amount into a glass of water and measure the result.

Anything under 7 is considered acidic, and anything over 7 is neutral.

What do you do with old mayo?

Once you’ve used up your mayonnaise, you can either toss it out or save it for later use.

There are plenty of uses for old mayonnaise, including salad dressing, sandwiches, and dips like lemon mayo sauce, mustard-mayo,…

One thing to keep in mind is that you should never reuse a jar of mayonnaise that’s already been opened.

Even though the ingredients inside haven’t changed, the acidity level has, which means that it’s not safe to consume.

Instead, you should wash the container and pour the contents into a clean vessel.

How long after expiration is mayo still good?

As mentioned above, mayonnaise is a perishable food, meaning that it will eventually spoil.

However, it’s generally safe to use after its expiration date.

While it’s impossible to say exactly how long your mayonnaise will remain safe, the USDA recommends that you avoid eating it after two years.

After that point, the risk of contamination increases significantly.

The same applies to any other perishable food, such as milk, cheese, and meat.

While these products aren’t technically “safe” beyond their expiration dates, it’s unlikely that they pose a significant health risk.

Air Fried Fish Sticks

Air Fryer Fish Sticks with Lemon Mayo Sauce

Fish sticks in the air fryer really up the game: they come out awesome, nice, and crispy. Since they are homemade they are more "meaty" and have less breading than store-bought. Try them on a sandwich!
Prep Time 20 minutes
Cook Time 10 minutes
Total Time 30 minutes
Course Appetizer
Cuisine American
Servings 4
Calories 719 kcal



  • Fish
  • 1 pound fish fillets
  • 1 cup breadcrumbs
  • 1/2 cup all-purpose flour
  • 2 eggs
  • 1 teaspoon salt
  • 1 teaspoon dried dill
  • 1/2 teaspoon ground black pepper
  • Cooking oil
  • Lemon
  • 1 cup mayonnaise
  • 1 lemon juice
  • 1 tablespoon olive oil
  • 1/2 teaspoon salt
  • 1/2 teaspoon dried parsley


  • On a cutting board, cut each fish fillet into 3 inches long and 1 inch wide pieces.
  • Put fish dry using paper towels.
  • In a medium-sized bowl combine flour with salt and pepper.
  • In another bowl beat the eggs.
  • Add breadcrumbs to a third bowl and season with dried dill.
  • Dip each piece of fish into the flour first, then eggs and then evenly coat with breadcrumbs. Shake off any excess.
  • Place fish sticks into the air fryer set to 400° F (200° C) for 10 minutes and spray them with cooking oil. Flip after 5 minutes and continue cooking for another 5 minutes or until golden.
  • To prepare the sauce, combine mayonnaise, lemon juice and olive oil in a medium-sized bowl. Season with salt and parsley and mix well.
  • Take the fish sticks out of the air fryer and serve with lemon mayo sauce. Enjoy!



Calories: 719kcalCarbohydrates: 33gProtein: 31gFat: 51gSaturated Fat: 9gPolyunsaturated Fat: 27gMonounsaturated Fat: 14gTrans Fat: 0.1gCholesterol: 162mgSodium: 1517mgPotassium: 474mgFiber: 2gSugar: 2gVitamin A: 172IUVitamin C: 3mgCalcium: 87mgIron: 3mg
Tried this recipe?Let us know how it was!

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