Does Protein Powder Expire?
March 29, 2017
If, like most people, you use protein powder as a supplement just to help fill in occasional gaps in your diet, there’s a strong chance that tubs of the stuff have a habit of sticking around for long stretches of time. When you do dig one out, then, you might very well find that the expiration has long since come and gone.
What then? Does protein powder really expire? How do you know when your protein powder is too old to use?
A Primer on Expiration Dates
In order to answer this question properly, it’s important that you understand one key fact about all packaged foods: Expiration dates are an estimate.
Actually, that estimated date isn’t even based on when the product is likely to spoil. Instead, it’s based on how long it takes for the flavor and texture of the food to change.
So, right away, one conclusion becomes clear. The expiration date doesn’t automatically mean that your protein powder is bad or unsafe to use. In fact, since protein powder is so dry, the chances of it going rancid or bacterial growth. Still, though, there are other things to consider.
Although the term is generally used in the singular, the reality is that there are lots of different types of protein out there, characterized by their amino acid profiles. When a protein contains all of the essential amino acids that your body cannot create on its own, it’s described as “complete.”
These complete proteins provide your body with absolutely everything it needs to recover from your workouts properly. Whey and casein – the two most popular protein powders out there – are both complete proteins.
At first, anyway. As these milk-based proteins sit, a process called Maillard browning kicks in. Put simply, this reaction causes one amino acid – lysine – found in your protein powder to breakdown. Once that happens, your protein is no longer complete.
Sadly, lysine is a very powerful muscle builder. Losing it, then, can take away the very reason that you’re taking protein powder to begin with.
How Old Is Too Old?
If you can’t trust the expiration date, though, how do you know when your protein powder is too old?
Trust your sense. If it tastes or smells off, ditch the powder and get a fresh tub. For the purists, though, you might get rid of that batch when the flavor starts to diminish since that’s a good sign that the Maillard browning has started and the powder is beginning to lose potency.
As a general rule, it’s safe to throw the powder away after it’s about a year past it’s sell-by-date.