How long can mayonnaise be left out?

In this brief guide, we are going to answer the question “how long can mayonnaise be left out” with an in-depth analysis of the shelf life of mayonnaise at room temperature. Moreover, we are going to discuss different ways to spot bad mayonnaise.

So without much ado, let’s dive in and figure out more about it.

How long can mayonnaise be left out?

Homemade mayonnaise lasts for about 2 hours when left out in the open. You should discard the mayonnaise that has been left in open for more than 2 hours as bacterial growth takes place at a faster pace between the temperature of 40 and 140 degrees Fahrenheit, therefore there are greater chances of the mayonnaise being already contaminated with bacteria when left out for more than 2 hours.

In the case of commercially processed mayonnaise, once you have opened the jar of mayonnaise, it lasts for about 8 hours when left out of the fridge at room temperature.

You should discard the mayonnaise that has been left in open for more than 8 hours at 50 degrees Fahrenheit as bacterial growth takes place at a faster pace between the temperature of 40 and 140 degrees Fahrenheit, therefore there are greater chances of the mayonnaise being already contaminated with bacteria when left out for more than 8 hours.

Moreover, commercially processed store-bought unopened mayonnaise lasts for about 3-4 months even after the “best by” date if it is stored in a cool, dry, and dark corner of your pantry away from direct sunlight and heat. You can also store an unopened jar of mayonnaise in the fridge if you want.

It is worth mentioning that these figures are just the estimated shelf life of the mayonnaise and it is the time during which you can enjoy its peak quality. 

What is the optimum temperature to store mayonnaise?

You should always store your mayonnaise at 40 degrees Fahrenheit or below in the fridge. Bacterial growth takes place at a faster pace between the temperature of 40 and 140 degrees Fahrenheit, therefore it is always advised to store mayonnaise at a lower temperature to preserve its freshness and quality for a long time.

Is mayonnaise safe to use after the best-before date?

The “best by” or “best before” date that is written on the carton of mayonnaise refers to the quality rather than safety so mayonnaise doesn’t necessarily go bad immediately after the best before date. 

This date refers to the time during which you can enjoy the peak quality and flavor of mayonnaise but you can still use mayonnaise that is past this date as long as it was stored properly, there is no leakage in the carton and no signs of mold are present.

Ways to spot bad mayonnaise

There are a couple of indicators that point out bad mayonnaise. You should consider the appearance, color, texture, smell, and taste of the mayonnaise to give a final verdict of whether or not it has gone bad.

Appearance

If you spot a mold or any other organic growth in the mayonnaise jar then it is better to get rid of it as it is an indication of bad mayonnaise. 

Moreover, the mold on the mayonnaise can produce mycotoxins. So if you see a visible mold on the surface of your mayonnaise then it is recommended never to smell such mayonnaise because the mycotoxins can enter your body via inhalation where they can disrupt your natural microflora that results in a weakened immune system.

Color

If you notice that your mayonnaise color has inclined towards a shade of yellow, if there are hints of yellow in your otherwise white mayonnaise, or if mayonnaise has a brownish tinge in it then it is better to discard such mayonnaise.

Texture

If the mayonnaise has separated to such an extent that you cannot even revive it after whisking then it is better to discard such mayonnaise.

Smell

If you smell some off-smells like something sour or putrid while taking a sniff test of your mayonnaise then it is an indication of bad mayonnaise and you should get rid of it.

Taste

If the mayonnaise has passed the visual and smell test, then you can go ahead and taste it. If you feel some off-flavors (sour or bitter) while tasting a bit of your mayonnaise then it may point out that your mayonnaise has gone bad and you should discard it.

Other FAQs about Mayonnaise which you may be interested in.

Can you cook mayonnaise?

How to tell if mayonnaise is bad?

Tips to properly store mayonnaise

  1. Unopened mayonnaise can be stored in a cool, dry, and dark corner of the pantry away from direct sunlight and heat for a long time. You can even refrigerate it to prolong its shelf life.
  1. Once opened, you should always store your mayonnaise at 40°F or below in the fridge. 
  1. It is better to store mayonnaise on a shelf of the refrigerator rather than the door as there is a lot of temperature fluctuation at the door of the fridge and that can harm the quality of mayonnaise.

You can read how to make mayonnaise here.

Conclusion

In this brief guide, we answered the question “how long can mayonnaise be left out” with an in-depth analysis of the shelf life of mayonnaise at room temperature. Moreover, we discussed different ways to spot bad mayonnaise.

Citations

https://www.stilltasty.com/questions/index/203#:~:text=Answer%3A%20You%20can%20let%20an,8%20hours%20should%20be%20discarded.
https://www.myrecipes.com/extracrispy/mayo-unrefrigerated-shelf-life
https://www.doesitgobad.com/does-mayonnaise-go-bad/

Hi, I am Charlotte, I love cooking and in my previous life, I was a chef. I bring some of my experience to the recipes on this hub and answer your food questions.