When you buy through links on our site, we may earn an affiliate commission.

Does Light Affect Coffee Beans?

Many of us stand blearily in front of the coffee machine every morning, waiting for our first cup of coffee to brew.

For those of us who take our coffee more seriously, we tamp carefully, descale our machine regularly and preheat our cup.

But are we taking care of our coffee beans before they come anywhere near our machine of java elixir?

The fact is that coffee beans are affected by light, so we should take extra care to store our coffee beans in a cool, dry, and darkened environment for maximum protection.

It will help if you pretend that your coffee beans are vampires. Not the shiny kind.

Now, if you’d like to know more about keeping your coffee beans fresher for longer, grab your cuppa and settle in for a (short) read.

Why Are Coffee Beans Sensitive to Light?

Coffee beans are sensitive to light.

We have established this, but the real question is why.

And the answer is photodegradation.

Photodegradation is the process whereby materials, foodstuffs like coffee, or even historical artifacts are altered by being exposed to light.

Coffee is also affected by electric light.

The absorption of UV rays alters coffee’s state, accelerating the breakdown of delicate chemical compounds and hastening decay.

This degradation affects the aroma and flavor and results in a rather stale cup of coffee.

Preventing light absorption is why when you buy coffee, whether ground or as beans, they are most often found in opaque packaging.

How Should I Store My Coffee Beans?

We have established light is bad, but what other factors affect the taste of your coffee?

The answer is heat, moisture, and air, AKA the three stooges.

Therefore, to avoid light and the three stooges affecting your coffee beans, you should keep them in an airtight and opaque container in a cool and dry area.

Don’t get me wrong, exposing your coffee beans to a little light won’t quite make them burst into flames and leave an ashy taste in your mouth, but repeated and lengthy exposure will cause your coffee to…not taste quite right.

The same is true for ground coffee, which is even more sensitive to light.

Glass and clear plastic containers are out, ceramic or opaque containers are in.

Which Roast Is Most at Risk?

Coffees are divided into roasts—light, medium, and dark.

I was curious, and so I learned that of the three dark roasted coffee beans are most rapidly affected by light.

This is because the beans from a dark roast are weaker and more porous than the other roasts.

ALSO READ: Light Roast vs Dark Roast Coffee: What’s The Difference?

Can I Freeze My Coffee Beans to Keep Them Fresh?

The jury is out on this! If you aren’t a big coffee drinker, but you do enjoy a perfect brew, then keep your coffee beans in the freezer until you need them.

There isn’t a lot of research on the impact of freezing coffee beans, but trust your palate and test out small quantities of frozen beans to see if you still like the brew. 

If you want to experiment, get someone else to make your coffee from frozen beans without telling you.

Then you can be objective about the taste.

What Can I Do With My Stale Coffee Beans or Ground Coffee?

Let me tell you, right now, you can’t salvage your coffee beans if they are stale.

You will know if the coffee beans are stale by the smell and taste of your coffee.

Use them for another purpose.

You can use ground coffee for exfoliating your skin or deterring insects.

Coffee can neutralize odors, and you can compost both beans and grounds.

The Takeaway!

What you need to take away from this is very simple.

Yes, coffee beans are sensitive to light!

Do right by yourself and your palate and store your beans or ground coffee correctly, away from the light!

Leave a Comment