How Long Does Mayo Last (Opened, Unopened Shelf Life + Expiration)

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How Long Does Mayonnaise Last? Expiration dates are a general guideline, but it also depends on many factors like whether it’s opened or unopened, homemade or store-bought, and storage conditions. Find out whether you can still use your mayo along with storage tips.

How Long Does Mayonnaise Last? Expiration dates are a general guideline, but it also depends on many factors like whether it’s opened or unopened, homemade or store-bought, and storage conditions. Find out whether you can still use your mayo along with storage tips.
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Mayonnaise is a delicious blend of creamy and tangy goodness that goes so well with both sweet and savory dishes. However, it’s an easily perishable condiment because of egg yolk, which is the main ingredient in its creamy constitution.

Egg yolk quickly goes bad when left out at room temperature. Commercial producers of mayonnaise have found a way to delay this with pasteurization. The procedure kills harmful bacteria that could grow if left unchecked and allows mayonnaise to last longer before expiring.

Once you open up a jar of mayonnaise, the clock starts ticking. So it’s important to know how much time you have until it expires.

How Long Does Mayonnaise Last?

Unopened mayo

How Long Does Mayo Last After Opening?

Experts recommend that you keep your mayonnaise stored in the refrigerator once you have opened it. For store-bought bottles such as Hellmann’s, the opened mayonnaise will remain in good quality for 2-3 months when refrigerated. The cold temperature in the fridge slows down the rate at which bacteria in mayonnaise grows, extending its shelf life.

How Long Does Mayo Last Unrefrigerated?

Mayonnaise is very perishable because egg yolk is one of the key ingredients in its composition. Once you open a jar, it has a shelf life of only about 8 hours if it is unrefrigerated. So if you’ve accidentally left it out overnight, it will be no good to you in the morning.

How Long Does Unopened Mayo Last?

An unopened jar of mayonnaise is shelf-stable for 3-4 months after its best by date. You can see the date written on the side of the mayonnaise jar. Three to four months is the shelf life when you decide to store it in the pantry. It can last for up to a year if left unopened and kept refrigerated throughout.

Photo showing homemade mayo in a clear mixing bowl.

How Long Does Homemade Mayonnaise Last?

The mayonnaise that you make at home can only last up to a week in the refrigerator. When this time passes, discard it because there is an increased risk of the salmonella bacteria developing in the egg yolk. Commercial manufacturers pasteurize eggs to prevent this, but the eggs you have at home may not have undergone pasteurization.

How to Store Mayonnaise?

An unopened jar of store-bought mayonnaise can be stored in your pantry, as it doesn’t require refrigeration. Keeping it in your refrigerator is also good because the cold temperatures will extend its shelf life.  Once you open a jar, always store it in your refrigerator until it is all used up. Store homemade mayonnaise in the fridge as well.

How Long Does Mayonnaise Last? Expiration dates are a general guideline, but it also depends on many factors like whether it’s opened or unopened, homemade or store-bought, and storage conditions. Find out whether you can still use your mayo along with storage tips.

How to Tell Mayo is Bad?

When you open a jar and see any mold or spore growth inside it, the mayonnaise is bad. A putrid smell, a darker shade of color than usual, and an off taste when you taste it are other signs of expiration in your mayonnaise.

What Happens If You Eat Expired Mayo?

If you experience some light stomach aches, it might not be too serious if your store-bought mayonnaise just expired. But go to see a doctor if you have severe pain in the stomach. If the mayonnaise was homemade, there is a high risk of getting food poisoning because of un-pasteurized egg yolk. It may be a breeding ground for salmonella after a week, so you should discard it.

What Can I Do With Expired Mayo?

Don’t toss out that jar of expired mayonnaise: there are still some ways for you to make use of it. Dab a little bit of it onto a dry cloth and rub your stainless steel appliances and silverware with it until they shine again! Put some of it in between squeaking hinges in your house and enjoy the noiseless opening and closing of doors and windows!

About Izzy

I'm Izzy, a food lover and photographer. Here you’ll find a collection of simple recipes that are perfect for busy people. My blog aims to help you make and enjoy delicious and healthy food at home.

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7 Comments

  1. Guess mayonnaise years ago could be stored in kitchen cupboard since that’s where my friend kept hers and never got sick! There were never expiration dates either so could keep opened jar in fridge for months never got sick!

    1. i found an unopened jar of Heinz cage free mayonnaise that’s been stored in frig; experation date is Feb 11, 2021. I rather hate the idea of tasting it, but what do you think? I appreciate what you wrote above
      Diane (also:))

      1. I had a newly opened jar of mayonaise and forgot to refrigerate it leaving it out when went on a trip for 2 wks so there it was on the shelf and wasn;t about to discard it and took a taste finding it tasted ok so used it never getting sick since it contains vinegar and had an acid pH.

    2. OKAY, Izzy, how do we find comments that have been sent to you about our topics? Now, I’ve eaten 50 year old home made pickles and they were the best I’ve ever eaten. Mayonnaise is another matter. We get away with a lot of questionable actions with food handling.

  2. Although it’s always best to error on the side of caution, I agree with you. Growing up We would have unopened mayonnaise In the pantry For a year Before we used it if it had been on sale. Also the opened mayonnaise stayed in the refrigerator for months. Perhaps they made it better when we were growing up. I am over 65 years old and and I’ve never been sick from
    eating bad Mayonnaise, hope I never do

  3. We do not all have a super strong immune system (good genes)
    I plan on keeping my homemade mayo for no longer than 2 days.

  4. I’ve been inserting mayonnaise in my anus after showering for years. It keeps me moist and there’s no dry feeling. Excellent if you have hemorrhoids or anal irritation.
    .