How long does miso last?
In the fridge, miso keeps for 1 year from the package date.
No guideline
1 year
from the package date
No guideline
Does miso go bad?
Yes. The fridge time above is the window USDA gives for good quality; after it, miso may still be safe for a short while but quality drops and spoilage signs start. The date on the package is the maker's quality promise; the times here count from purchase unless marked "from the package date".
Two numbers to keep in mind: a fridge at 40 F (4 C) or below, and no more than 2 hours at room temperature (1 hour above 90 F / 32 C) for anything perishable.
How to tell miso has gone bad
General signs for vegetarian proteins, the group USDA lists miso under.
- Sour or off smell instead of a neutral, mild scent
- Slimy film developing on the surface of tofu
- Discoloration, especially yellowing or dark spots
- Mould, often black or white, on tempeh
- Packaging that has swollen or lost its seal
More on vegetarian proteins. The times above are quality guidelines, not safety limits; food that shows these signs goes out regardless of the date.
How long do other vegetarian proteins last?
Source: USDA FSIS FoodKeeper dataset (public domain). How we decode the data.