Does Whey Protein Go Bad

If you’ve bought a few more containers of whey than you needed at a time, the question “does whey protein go bad?” came up right after that realization. We often buy supplements in bulk to save money and often overestimate our needs.

Or maybe you’ve bought just a package or two of protein powder, then had a few-months-long break with your workouts and stopped drinking additional protein. Now you’re getting back to your routine and aren’t sure if you can still use the protein supplement you bought some time ago.

I’ve been there, and I’ve got some good news for you: if you stored the protein powder properly, and it’s only a few months past the date on the label, the powder is most likely still fine.

If you would like to learn more about storage, shelf life, and signs of spoilage of whey protein, read on.

Drinking a protein shake
(credit: Derick McKinney)

How To Store Whey Protein

The best way to prolong the life of your protein powder is to ensure proper storage.

Things that are going to affect whey protein are light, temperature, and exposure to bacteria and moisture. For best results, store the container in a cool, dark and dry environment. The pantry is the best choice, but a cabinet in the kitchen works fine too.

Once you open the package for the first time, make sure the powder is always in an airtight container, so moisture and any contaminants cannot reach it.

Most whey protein supplements come in a big plastic jar that’s easy to open and seal tightly. If that’s the case, you can use that jar to store the powder. If your WPC came in a container or package that you cannot seal easily, you need to transfer it to such a container after opening the package.

I usually keep one or two empty jars of whey protein just to have some containers I can use for that purpose.

Getting ready for a workout
(credit: Brandless)

How Long Does Whey Protein Last

As almost all products available on the market, whey protein has a “best by” or “use-by” date on the label. This date is usually pretty long, like 12 to 18 months after the production date, or even more.

The best-by date isn’t an expiration date, and whey protein won’t go bad overnight when it’s past that date. It should easily last a few months longer, provided you do a good job of storing it.

It’s tough to say how long exactly will whey protein last. All we can do is estimate that time.

For an unopened package of whey protein, it should stay okay for at least 6 to 9 months past the date on the label. Please note that you can find a whole lot of people online who prepared whey protein that was three years after the best-by date and it still came out fine.

When it comes to open whey protein, it should last for at least 3 to 6 months after the best-by date. The reason for this is that opening the package increases the chance of the powder accumulating bacteria or moisture. As long as water doesn’t get into the powder, it should be safe to consume.

Protein shake
Image used under Creative Commons from Adam Pieniazek

When it comes to the shelf life of whey protein, there’s one more thing you need to know.

Some whey protein supplements also include additional vitamins that are not present in whey isolate naturally.

Over time, those vitamins might lose their potency. That doesn’t mean the powder will become bad or spoiled, but its nutritional value will be decreased. The same happens with fortified powdered milk.

 Pantry
Whey Protein (Closed)“Best by” + 6 – 9 months
Whey Protein (Opened)“Best by” + 3 – 6 months

Please note that the dates above are approximate and whey protein should last much longer if stored well.

How To Tell If Whey Protein Is Bad

As I mentioned earlier, whey protein shouldn’t go bad unless water or any contaminants get inside the container.

The first thing to consider is the look and smell of the powder. They will give you a hint if it has gone bad yet.

If you see any clumps, this is a sign that moisture has found its way inside and you should discard the whey protein. Same thing if the smell is off.

Provided that the look and smell are okay, you can give it a taste by preparing and drinking a small amount. If you notice anything unusual after preparation, like an off smell or bad taste, throw it away. If everything is as it is supposed to, feel free to continue using the powder.