Does Pesto Go Bad?

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Pesto is a concoction of fresh basil, olive oil, Parmesan cheese, and pine nuts.

It has a short shelf life and will go bad within a few days of being made.

Does Pesto Go Bad

How do you know if pesto has gone bad?

You’ll know when your pesto has gone bad if it’s moldy or smells musty.

If you’re not sure whether it’s gone bad, try tasting it.

You may notice an off-taste or bitterness in your mouth after eating it.

The aroma won’t be as strong either.

In addition, you might see small black spots on the surface of the pesto.

What are some signs that pesto has gone bad?

The first sign that your pesto has gone bad is a change in its appearance and flavor.

The color may turn brownish green or brownish purple.

It could also have a bitter or musty odor.

The flavor could become weak or lose its freshness.

The aroma may fade quickly as well.

How long does pesto last?

Fresh pesto should stay good for about two weeks stored in the refrigerator.

Once it starts to expire, there’s not much you can do to save it.

To extend its storage time, you can use dried pesto.

But don’t store it in the sun because this will cause the basil to spoil.

Does pesto need to be refrigerated?

Yes, pesto needs to be kept cold.

Even though it lasts for only a couple of weeks, you still want to keep it chilled at all times.

This is especially important for people who make their own pesto at home.

Can you freeze pesto?

No, you cannot freeze pesto.

When you freeze food, it changes its texture and becomes mushy, which makes it difficult to serve.

However, you can freeze the ingredients separately so that when you make your pesto again, you can add them back into the freezer container.

How would you describe the taste of bad pesto?

When you buy pesto that has gone bad, you probably won’t even recognize it as pesto.

It tastes bland and watery.

The smell doesn’t help either since it often has a foul odor.

And it may even look gray or pale green instead of bright red.

What happens if you eat bad pesto?

If you eat too much of it, you may get sick.

You could experience nausea, stomach pain, diarrhea, fever, headache, and other symptoms.

These symptoms usually happen within 24 hours after consuming pesto that has expired.

According to the Mayo Clinic, you shouldn’t consume any more than one serving per day of pesto that has gone bad.

For example, you’d need to divide one cup (250 grams) of pesto by three servings per day.

Or, if you’re using a tablespoon (15 milliliters), then you’d need to divide that by four servings per day.

How can you tell if pesto has been contaminated?

One way to determine whether your pesto has been contaminated is to check the expiration date.

If you find that the date has passed, then the pesto is likely spoiled.

Another way to tell is to open the jar and take a sniff.

If the odor is sour, moldy, or rotten, then it’s most likely contaminated.

Is it safe to eat pesto that has been left out?

If the pesto hasn’t expired yet, then you can probably eat it without worrying about contamination.

However, if you leave it out for more than a week, you should throw it away.

The longer the pesto sits, the less flavorful it gets.

Does Pesto Go Bad? 1

What should you do with pesto that has gone bad?

You should discard any pesto that’s expired or contaminated.

You can use it up by making pasta or adding it to another dish.

However, if you’re going to use it for a salad, you should toss it before serving.

The dish with only 10 minutes of your time, the Ultimate Chicken and Pesto Sandwich gives a traditional dish a contemporary spin. Let’s try!

Is it safe to eat pesto that has been left out?

If you decide to use it, make sure that you’re not allergic to anything in it.

Then, follow these steps to ensure that you can safely enjoy it.

Afterwards, you can serve it straight out of the container or transfer it to a smaller container.

Just make sure that you cover it with plastic wrap or aluminum foil once again.

If you’re not familiar with how to properly prepare pesto, we recommend checking our guide here.

We’ve also got information on how to make homemade pesto.

For more great articles about food and cooking, check out the links on the next page!

Wash the pesto thoroughly under running water to remove dirt and bacteria.

Remove the lid and place the pesto in a bowl or container that’s large enough for you to spread it around.

Cover it with plastic wrap, foil, or plastic bags.

Let it sit for 24 hours in order to allow the flavors to develop fully.

Chicken for Chicken and Pesto Sandwich

The Ultimate Chicken and Pesto Sandwich

I urge you to try these deliciously stacked club sandwiches. Loaded with pesto chicken, sliced avocados and sun dried tomatoes, this recipe offers a modern twist to a classic meal for only 10 minutes of your time.
Prep Time 10 minutes
Cook Time 5 minutes
Total Time 15 minutes
Course Breakfast
Cuisine American
Servings 4
Calories 528 kcal


  • 1 Pan
  • 1 bowl
  • 1 Toaster Oven


  • 4 skinless, boneless chicken breasts
  • ½ cup pesto
  • 1 tbsp oil
  • salt and pepper
  • 4 slices mozzarella cheese
  • 4 tbsp tomatoes
  • 2 avocado pitted and sliced
  • Rye
  • Butter


  • Heat the oil in a pan over medium heat.
  • Wash and slice the chicken breasts in halves, then place them in a bowl.
  • Mix in the pesto, salt and pepper until evenly coated
  • Cook the chicken, covered, for 3-5 minutes on each side, or until no longer pink.
  • Meanwhile, toast the bread in a toaster or broil in the oven on its lowest setting for 1-2 minutes on each side.
  • Add butter to toast.



  • Top bread with (half) sliced avocado, 2 halves of chicken, 1 piece of mozzarella and 1 tbsp of sun dried tomatoes spread over.
  • Optional: Place sandwich back on the pan over medium heat, covered, for 30 seconds or until cheese is melted. Cut into half or quarters and secure with toothpick to serve.


Calories: 528kcalCarbohydrates: 12gProtein: 34gFat: 39gSaturated Fat: 9gPolyunsaturated Fat: 3gMonounsaturated Fat: 15gTrans Fat: 0.03gCholesterol: 97mgSodium: 606mgPotassium: 962mgFiber: 7gSugar: 2gVitamin A: 1120IUVitamin C: 13mgCalcium: 212mgIron: 1mg
Keyword The Ultimate Chicken and Pesto Sandwich
Tried this recipe?Let us know how it was!

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