Can Pesto Go Bad?

Pesto is a sauce made from fresh basil, pine nuts, and olive oil. It is often used as a sauce for pasta as well as a dip or as a sandwich spread. Since pesto sauce is made with fresh basil, along with other ingredients high in oil, its shelf life is quite limited.

The good news is since pesto sauce has plenty of uses, you’ll have no trouble using up your supply in a flash! Still, this sauce is quite delicate so storing it properly is a critical part of extending its shelf life. This goes especially for homemade pesto that’s free of preservatives.

Image used under Creative Commons from Marco Verch

Can Pesto Go Bad?

As with any type of sauce made from fresh, oily ingredients, pesto will go bad at some point. The storage life of pesto oil is limited because the olive oil and pine nuts are high in oils that could go rancid much faster than the other ingredients. That’s why if you’re making pesto sauce from scratch, we highly recommend making small batches of it rather than a massive batch that you cannot use up in a week or less.

Thankfully, several storage techniques could extend the shelf life of the sauce past its expiry date. You see, the storage conditions of the sauce will affect its shelf life. By being mindful of how to store pesto, there is no reason why you couldn’t extend the storage life of this beloved sauce.

Signs that Pesto Has Gone Bad

It is easy to tell if pesto has gone bad, check for significant discoloration. Fresh pesto sauce is a vivid shade of green but will oxidize over time. The oxidation usually at the top, spots that were not submerged well in oil.

The olive oil prevents oxidation but it won’t keep the sauce from turning brown for long. If the pesto has been kept in storage for too long, it will turn an odd shade of brown. Check the aroma of the sauce. If it smells rancid, like old oil, discard the product. If the pesto sauce tasted weird in any way, the sauce may have gone bad.

How to Store Pesto?

The best way to store pesto is to keep it in the refrigerator. The chilly temperature will inhibit oxidation and delay the degradation of the ingredients. Refrigeration will also keep the oils from going rancid. You can use the product’s original packaging to store the product.

Image used under Creative Commons from Marco Verch

The same can be said for homemade pesto sauce, just stick it in the fridge! Always keep the lid tightly closed after every use to reduce oxidation and minimize air exposure. When kept in the fridge, an unopened bottle of pesto will keep for a maximum of 3 weeks. An opened bottle of pesto sauce will keep for 2 weeks in the fridge. As for homemade pesto, it will only keep for a week or so.

Can You Freeze Pesto?

Yes, you can freeze pesto sauce to extend its shelf life. This goes especially for homemade pesto that’s free of preservatives as well as sauce that’s nearing its shelf life. Simply spoon the sauce into an airtight container, leaving a few inches of space before closing the lid. Keep the airtight lid secure so the sauce won’t leak out. Write the storage date then stick in the freezer.

We highly recommend packing the product into manageable portions so you don’t have to defrost the entire container for a single serving of pesto sauce! When kept in the freezer, store-bought pesto sauce will keep for 8 months or so. Homemade pesto will stay fresh for 4 months.

Summary

Nothing like a little pesto sauce to bring your favorite pasta dishes and sandwiches to life! Can pesto go bad? It will go bad if you didn’t store it properly. Just keep the storage tips we’ve outlined above in mind to maximize your supply!

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