Do Sunflower Seeds Go Bad?

Found an old pack of sunflower seeds and not sure if it’s still okay to eat or not? You have probably bought it to snack on while watching the game and forgot about it in all the excitement.

Now, a couple of months later, the package still sits in the cabinet in the pantry where you tossed it. Do sunflower seeds go bad?

In this short guide, we talk all about storage, shelf life, and spoilage of sunflower seeds. If that’s what you’re interested in, read on.

Sunflower seeds in a black scoop
Sunflower seeds in a black scoop

How To Store Sunflower Seeds

There are a couple of options when it comes to buying sunflower seeds. You can buy them in-shell or shelled (sunflower kernels), roasted, salted, and sometimes even flavored ones are available. But no matter the variety, the same storage guidelines apply.

In the supermarkets, sunflower seeds sit on the shelves near trail mix and many varieties of nuts. And while that setting is far from ideal, it’s okay for the short term (i.e., a couple of months). If you buy the package to snack on during the game next week, it’s okay for it to sit at room temperature. Just make sure it’s in a dry place and away from sunlight, and you’re good to go.

But if you’ve bought the seeds in bulk, or you might need to store them for longer than a month or two, a cabinet in the pantry is not enough. A much better option would be to chill it in an airtight container in the fridge or freezer (HL). The cold temperature helps protect the seeds against rancidity, the most common cause of sunflower seeds going “bad.”

Tip

To prolong the shelf life of sunflower kernels and seeds, keep them in a low oxygen packaging (NSA). So if you’ve bought the seeds in bulk or already opened the package, transfer them into a resealable freezer bag and squeeze out the air before sealing.

Sunflower seeds closeup
Sunflower seeds closeup

How Long Do Sunflower Seeds Last

While I probably could provide you with separate storage periods for unshelled, shelled, roasted, and not roasted sunflower seeds, the differences between those are quite small. Therefore I’m going to keep things simple.

For commercially bagged sunflower seeds, look at the best-by date on the label. It’s not an expiration date by any means, but an excellent place to start. If the package stays unopened at room temperature, the seeds should keep quality for a couple of months past it. If you decide to refrigerate or freeze them, expect to get at least a year of additional shelf life.

Sunflower seeds in a white cloth bag
Sunflower seeds in a white cloth bag

For sunflower seeds bought in bulk, or an opened package, the time when the quality stays best is much shorter. If you keep the seeds sealed well in a cabinet in the pantry, they should keep for at least 2 to 3 months. To prolong that to a whole year, go with refrigerating or freezing them.

PantryFridge
Commercially packaged sunflower seeds (unopened)Best-by date + 2 monthsBest-by + 12 months
Sunflower seeds (open package, or bought in bulk)2 – 3 months12 months

Please note the periods above are estimates and for best quality only. It’s not unlikely that you will find seeds that are way past these periods and still okay to eat.

Pile of sunflower seeds
Pile of sunflower seeds

How To Tell If Sunflower Seeds Are Bad?

The signs of spoilage of oily seeds like sesame, pumpkin, or sunflower seeds, are quite similar. Here are things to look out for:

  • Rancid or sour smell. The number one way of oily seed spoiling is them going rancid. Rancidification is basically oxidation of oils due to exposure to air, light, or moisture (WIKI). You won’t be sick after eating rancid sunflower seeds, but the smell (and usually taste) will be quite bad. Discard if the seeds smell off.
  • Off taste. Sometimes it’s not clear right away that the seeds are spoiled based on their aroma. If that’s the case, giving one or two a taste to make sure the quality is still okay is the way to go. If the seeds taste sour, get rid of them.
  • Mold. Mold comes last because it’s quite unlikely for it to show up. If you follow the storage guidelines and don’t let any water into the package, there most likely won’t be any there.
Tip

If you’re not entirely sure that the seeds are good to eat, discard them. Human intuition when it comes to spotting foods that are unsafe to eat is quite good. If you feel that something is wrong about the seeds, trust the instinct.

Sunflower seeds
Sunflower seeds

Sources