How Long Does Miso Soup Last in the Fridge?

If you’ve ever made miso soup at home or taken home leftovers from a Japanese restaurant you may wonder, “How long does miso soup last in the fridge?”

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So how long does miso soup last anyway? If you store miso soup in the fridge it will last for 2-3 days. In the freezer miso soup will last for 6 months.

Read the rest of the article to learn more about how to tell if miso soup has gone bad, the best type of container to store it in, and more!

How long can you store miso soup in the fridge

Miso soup can stay fresh in the fridge for at least 2-3 days as long as it is stored in an air-tight container.

How long does miso soup last in the freezer 

If stored properly miso soup can last in the freezer for up to 6 months. For more detailed information on how to properly freeze miso soup check out this post, “How to freeze miso soup.”

How Do You Know If Miso Went Bad?

1. Mold Growth: If mold or any type of bacterial growth is present the miso soup is spoiled. Mold starts with spores and spreads. It’s commonly found on fruits and vegetables, but mold can grow on any fresh surface. Mold can grow in hidden locations so make sure you check underside of the lid for mold or discoloration.
2. Sour Taste: Spoiled food tastes bitter, sour or fermented. If your hummus tastes sour its a good indication that it has gone bad. Make sure to spit it out immediately so that you don’t get food poisoning. Miso soup will naturally become more sour the older it gets. This is a natural part of the fermentation process. But once the soup tastes very sour it has spoiled and is no longer safe to eat.
3. Distinct Fishy Smell – Miso soup smells kind of nutty when it’s fresh. If it starts to smell fishy it has gone bad. If it smells fishy its best to be on the safe side and throw it out.

Signs of Food Spoilage

1. Slimy Texture
2. Mold Growth
3. Sour Taste
4. Bad Smell
5. Change in Color or Texture

Can Eating Old Miso Soup Make You Sick

Yes, eating old miso soup can make you sick. While miso itself rarely spoils because the salt content in it acts as a preservative. Miso soup is prone to bacterial and fungal growth. Consuming harmful bacteria will lead to food born illnesses like:

• Campylobacteriosis
• Cryptosporidiosis
• Cyclosporiasis
• E. coli
• Giardia
• Listeria

These illnesses can cause symptoms including:

• Nausea
• Diarrhea
• Vomiting
• Muscle Cramps
• Fever
• Weakness

Why Should You Not Boil Miso?

No you should not boil miso! Miso soup broth is filled with tons of beneficial bacteria for your gut health. These beneficial bacteria are known as probiotics. While probiotics can survive extremely cold temperatures they don’t do well in hot temperatures. Overheating the soup when you reheat it will certainly kill off any live probiotics quickly. Live probiotic cultures are destroyed at around 115°F. So if you are cooking miso soup fresh you would wait until the end of cooking to stir in the miso paste. 

When re-heating soup, the probiotics are already inside. So if you want to make sure you aren’t sabotaging your probiotic intake gently re-heat the soup to 110°F maximum before you eat it. Don’t let the soup simmer or boil. For more detailed re-heating instructions checkout the section on how to reheat miso soup below.

How Can I Make Miso Soup Last Longer

The solids in miso soup will spoil quickly no matter how you store them. However you can ensure that you’re leftover miso soup will stay fresh for a full 2-3 days by storing it in an airtight container.

• Store the broth and solid items separately
• Use clean spoons
• Store in an airtight container

Another way to make miso soup last longer is to store the miso broth and solid items separately. Doing so will lengthen the shelf life of your miso soup broth by up to two days. So the miso soup broth will stay fresh for up to five days while the solids will be edible for two days.

If you can store the tofu separately from the soup this will help ensure that the tofu doesn’t get soggy when you reheat it.

You can also ensure that your miso soup stays fresh longer by making sure that you use clean utensils to ladle the soup into the storage container. If you use dirty spoons then you will contaminate the soup with bacteria. This bacteria will spoil the soup faster.

Can You Freeze Miso Soup?

Yes, you can freeze miso soup. Freezing miso soup is a great way to preserve the freshness and flavor of your leftover miso soup. Luckily, freezing miso soup will not change its taste or texture. For more details about how to freeze miso soup the best way check out this article I wrote about freezing miso soup!

How To Freeze Miso Soup

Freezing miso soup is easy to do! Just follow these step by step instructions:

1. Once you’re done cooking the soup remove it from the pot and break the soup down into single serving portions in 1 pint containers.
2. Leave the lids off of the containers and line them up on the counter. Breaking the soup down into smaller portions will help it cool off faster. You need to wait until the soup’s temperature cools down to room temperature before you can safely put the lid on the soup. If you put the Tupperware lid on the soup when it’s still hot the heat will create a vacuum seal. This will make the soup harder to open.
3. Place the soup in the freezer and allow it to freeze over 4-6 hours.