How Long Do Protein Shakes Last? (I Tested It)

I tested how long protein shakes can last both at room temperature and in the fridge.

Here was the result:

Protein shakes last for up to two hours at room temperature, or up to three days if they are refrigerated and stored in an air-tight container. Protein shakes may not stay fresh for as long if they contain fruit, vegetables, nuts, or other supplements because these ingredients break down faster than others.

If you’re wondering whether your protein shake has gone bad or not, I’ve included some tell-tale signs below to watch out for.

Key Takeaways

• Protein powder itself has a shelf life of 1 to 2 years but should be stored in a cool dry place to ensure it doesn’t expire sooner.

• Changes in color, odor, taste, and texture are signs that your protein shake has gone bad and that you should not consume it.

• Refrigerate your protein shake if you don’t plan to consume it within 2 hours of mixing it.

Can Protein Shakes Go Bad?

Yes, protein shakes can go bad because once they are mixed, the water content in a protein shake makes it more susceptible to chemical and physical processes that make food go bad in just a few days. 

Protein shakes could also go bad because of the protein powder that you’re using. Dairy protein powders (whey, casein, or milk protein powders) and soy protein powder usually have a shelf life of 1-2 years.

Plant-based protein powders (except soy) have the longest shelf-life and are generally good for up to 2 years (or more) if they are properly stored in a tightly sealed container in a cool, dry, dark place.

That said, protein powders can go bad before their expiration date if they’re stored in a warm or humid environment. You can tell that your protein powder has gone bad if it’s starting to clump in the container, it’s not mixing as well in your shake, or it’s starting to smell like garlic.

Ready-made protein shakes usually do not require refrigeration and they can be safely stored for 9-12 months before they are opened. You can tell that a ready-made shake has gone bad if it smells like spoiled milk.

Once a shake is mixed up (or when a ready-made protein shake is opened), the timeline goes from months or years to mere hours or days.

Do Protein Shakes Have to Be Refrigerated?

Protein shakes do not have to be refrigerated if you’re going to drink them right away; however, if you’re not drinking them within 2 hours of mixing, then you will need to refrigerate them.

Protein shakes can’t be left out for more than 2 hours because the amino acids in protein will spoil if left out at room temperature for too long once they’re mixed with liquids. 

Ready-made protein shakes are different because they have been sealed and preserved properly so that they can be left out at room temperature until they’re opened.

How Long Will A Protein Shake Last In The Fridge?

A protein shake will last in the fridge for up to 72 hours if the temperature is 40 degrees Fahrenheit (4 degrees Celsius) or colder, and the shake is stored in an airtight container with a properly sealed, tightly fitting lid.

How Long Will A Protein Shake Last At Room Temperature?

A protein shake will typically last up to 2 hours at room temperature; however, it could go bad more quickly if it’s unusually warm or humid because the amino acids in your shake will degrade more quickly in warmer temperatures.

Can You Make A Protein Shake Ahead Of Time?

Yes, you can make a protein shake ahead without compromising its quality or benefits as long as it’s properly stored. You may want to make your shake ahead of time to save time and make it more convenient.

For example, if you workout after work then you may want to make your protein shake before you go to work and store it in the fridge until after your workout.

Another situation where it pays off to make your shake ahead of time is if you workout first thing in the morning.

It’s much more convenient to make your shake the night before and be able to grab it and go, rather than having to prepare it in the morning when you’re tired.

Some of my clients like to make protein shakes ahead of time as part of their meal prep.

They will mix up protein shakes for the next three days along with their other meals and snacks, since pre-planning and preparing foods make it easier to hit their macros.

How Do You Know If Your Protein Shake Has Gone Bad?

There are some telltale signs that your protein shake has gone bad. But, if you’re ever unsure, follow the guideline: when in doubt, throw it out!

1. The odor: if your protein shake smells “off” (like sour milk), it’s one of the first signs that your protein shake has gone bad.

2. The look: if the appearance of your protein shake is unappealing because it has started to change colors, or if it has spots, it’s time to throw it out.

3. The texture: if your protein shake is lumpy with clots or curds, or slimy and sticking to the sides of the container, it’s no good.

4. The bubbles: it’s one thing to have a foamy protein shake (harmless), but if your protein shake is actively releasing gas that is making the lid swell, then it’s fermenting and it’s now a science experiment and not a shake for you to drink.

5. The taste: if you’re actually brave enough to taste the shake at this point, if it tastes funny or weird or “off” in any way, get rid of it.  Even if you think it tastes fine, if you notice any of the other signs above, don’t risk it.

6. The expiry date: if the expiry date has passed on a ready-made protein shake or on your protein powder, throw it out.  Don’t make a protein shake with expired protein powder, even if none of the other signs above is present.

What Happens If You Drink A Protein Shake That’s Gone Bad?

At best, if you drink a protein shake that has gone bad, you’ll have an unpleasant taste and/or texture and experience mild gastrointestinal issues. At worst, you can get a serious case of food poisoning that leads to vomiting and severe diarrhea requiring medical attention. It’s not worth it!

What Does It Mean If Your Protein Shake Changes Color?

If your protein shake has changed color, it has started to react with the air around it. Your shake may or may not still be safe to drink, depending on whether it is just harmless browning of fruit in the shake, or if the color is a sign that the shake has gone bad or contains mold. 

If your protein shake contains fruit, the fruit will start to turn brown due to enzymes in the fruit reacting with the air – this is what happens when you see apple slices starting to turn brown not long after you cut them.

Fruit turning brown and causing your shake to change color isn’t a concern and is actually still safe to consume, but it could compromise the taste of the shake and you may not enjoy it as much.

Here you can see that the blueberries in my protein shake started to turn brown when I left the shake in the fridge overnight.  But, the shake was still fine to drink.

However, if there are no fruits in your shake and your shake has changed color then this could be a sign that your shake has gone bad. 

If your protein shake is starting to turn yellow, it’s a sign that it is starting to curdle (go bad), the same as what happens with expired milk.  It’s not safe to drink – ditch it and get a fresh shake.

If your protein shake or protein powder itself has any purple, green, blue, gray, or black spots, then watch out because these are usually mold spores. 

These spores can be very pale at first, and mostly white with just a small amount of color in the center, so watch out for any spots at all and throw away any shake or powder if you see them.

• Related Article: Is It Bad To Drink An Expired Protein Shake? (Yes, Here’s Why)

How To Make Your Protein Shake Last Longer

If you are going to make your protein shake ahead of time, here are my tips for making it last longer:

1. Mix with only water or milk: the sugars and acids in juice, especially citrus (like orange juice) will react with the protein and cause it to break down more quickly.  A protein shake made with only water or milk will last longer.

2. Avoid fruit: similar to avoiding juice, avoiding fresh or frozen fruit in your protein shake will keep the protein from reacting with the sugar and acid in the fruit.

3. Use the right container: be sure to store your protein shake in a bottle with a tightly-fitting screw-on lid, or a shaker cup with a snap-on lid that is watertight.  Don’t leave it in a glass or cup that is open to the air, because the oxygen will react with the ingredients and break them down (oxidation).

4. Store at a cold temperature: ensure your fridge is 40 degrees Fahrenheit (4 degrees Celsius) or colder to slow down chemical reactions and bacterial growth.

Frequently Asked Questions

How Long Can I Keep Protein Shakes?

You can keep protein shakes for up to 2 hours at room temperature (ideally you would drink them right away once they are mixed, or opened, in the case of ready-made protein shakes), or you can refrigerate them in a sealed container for up to 72 hours. Homemade shakes won’t last as long if they have fruit or juice.

Do Protein Shakes Really Expire?

Yes, protein shakes do expire, even protein powder itself expires. Ready-made protein shakes have a shelf life of 9-12 months before they are opened, but once they are opened they should be consumed within 2 hours, or they will last in the fridge up to 3 days. The same is true for homemade protein shakes once they are mixed.