Is moldy miso paste safe to eat?
Quick Answer
No
Moldy miso paste should not be consumed as it can contain harmful bacteria and toxins that can cause food poisoning.

What Is It?
Miso paste is a traditional Japanese seasoning made from fermented soybeans. When it becomes moldy, it means that unwanted bacteria or fungi have started to grow on it.
How to Tell
Moldy miso paste can have a strange smell, discoloration, or visible mold growth. The texture may also become slimy or fuzzy.
Why It Can Be Risky
Eating moldy miso paste can pose several health risks.
- Food poisoning: Mold can produce harmful toxins that can cause food poisoning symptoms such as nausea, vomiting, and diarrhea.
- Allergic reactions: Some people may have allergic reactions to mold, which can cause symptoms like itching, swelling, and difficulty breathing.
- Respiratory problems: Inhaling mold spores can cause respiratory problems, especially in people with asthma or other respiratory conditions.
Safe Method?
If you see a small amount of mold on the surface of the miso paste, you can scrape it off and use the rest. However, if the mold has spread throughout the paste, it’s best to throw it away.
Can You Just Cut It Off?
If more than a quarter of the miso paste is covered in mold, it’s best to discard the entire container.
Safe Alternatives
If you don’t have fresh miso paste, you can use soy sauce, tamari, or dashi as alternatives in your recipes.
Storage Tips
Store miso paste in a sealed container in the refrigerator to prevent mold growth.’, ‘Avoid using wet or dirty utensils to scoop out the paste, as this can introduce bacteria.