How long does Parmesan last?
Unopened, it keeps in the fridge for about 6 months. Once opened, it keeps in the fridge for about 3 weeks.
Product: A vacuum-packed wedge of Parmesan.
Shelf life of Parmesan at a glance
| Storage | Unopened | Opened |
|---|---|---|
| Fridge | 6 months | 3 weeks |
| Freezer | 6 months | – |
Once opened, wrap it in cheese paper or keep it in a cheese container in the fridge rather than airtight in plastic wrap. Small spots of mold on hard cheese can be cut off generously; throw it out if there are several spots or the cheese turns moist and soft. Pre-grated Parmesan keeps for less time once opened.
Does Parmesan go bad?
Food past its date has not necessarily gone bad. The times on this page are guideline values for food stored properly. In the US, date labels are not required by federal law (infant formula is the exception), and most of them describe quality, not safety. A "Best if Used By" date is not an expiration date, and many products are still fine after it. A "Sell By" date is meant for the store, not for you. Look at the food and smell it before you taste a little. Mold, an off smell or a bulging can or lid means it goes in the trash. Take a "Use By" date on perishables such as meat, fish, deli meats and dairy seriously: eat or freeze them by that date.