Storing your coffee beans correctly will keep them fresh for longer. But one thing I’ve always been curious to know is whether or not coffee beans are sensitive to light. I did a bit of research to find out.
Are coffee beans light sensitive? Coffee beans are sensitive to light due to a process called photodegradation, where photons break down organic compounds in the beans. This causes the beans to become less aromatic and go stale more quickly. You can prevent photodegradation by storing coffee beans in a dark place.
Read on to learn why this happens and how you can store your beans to prevent it.
Why coffee beans are sensitive to light
Coffee beans, like just about every type of food, break down and degrade over time. There are many reasons for this including temperature, chemical reactions, micro-organisms, among other reasons as well.
But one of the lesser known causes of coffee bean spoilage comes from light. Coffee loses its freshness from light because of a process called photodegradation which breaks down polymer chains in the beans when photons come into contact with them.
This is different from spoilage caused by heat or infrared wavelengths. Photodegradation only applies when coffee beans are exposed to light in the ultraviolet light spectrum, which includes non-visible light such as UV light.
Why coffee beans are especially sensitive to UV light
UV light happens to fall within the spectrum of light that causes photodegradation to occur in coffee beans. There are other forms of light that will also cause your coffee to stale more quickly. However, the abundance of UV light we’re exposed to makes it the most likely cause.
Are whole beans or grounds more light sensitive?
Coffee grounds are more light sensitive than whole beans because they have a larger surface area. The more area that is exposed to light, the more quickly the photooxidative process occurs.
As a result, ground coffee will go stale from photodegradation much more quickly than whole beans. To maximize the longevity of your coffee, and to improve your beverage’s overall taste, it is recommended that you freshly grind your coffee beans right before brewing.
How to protect your coffee beans from UV light
The best thing to do is store your beans in an opaque container that blocks out all light. This eliminates photodegradation from occurring altogether.
Most coffee beans are sold in opaque bags, which are fine. Ceramic airtight containers are an excellent choice for those who choose to store their beans in a more accessible container.