What’s the scoop on oily coffee beans?
That oily sheen you see on the outside of your coffee beans is the result of a chemical reaction. As coffee beans are roasted, the cell-structure of the bean begins to break down, and CO2 is released. It’s the chemical reaction between the CO2 and oxygen that leaves behind an oily appearance on the coffee beans. We tend to call this “the oils coming to the surface.”
Is it bad if a coffee bean is oily?
Not necessarily. A dark roast, or French roast coffee bean will appear shiny and oily due to its longer roasting time. The longer it roasts, the more of that cell-structure is broken down, the more Co2 is released and comes in contact with oxygen… the more oily the surface of the beans. If you compare our Backdraft beans (Backdraft is our most popular dark roast) to our Einstein beans (Einstein is a popular medium roast), for example, you will see the difference.
What if my coffee beans are not dark-roast?
If you’re ordering a medium or light roast coffee, then your coffee beans should appear more dry. The fresher your coffee, the less oils you should see on medium or light roast coffee beans because they have had less time exposed to oxygen, and therefore less chance for that chemical reaction to occur. This is one of the reasons we recommend storing your unused coffee in an airtight container (the foil bags we use to ship coffee are heat-sealed and come equipped with a one-way valve that lets the CO2 escape, but doesn’t let any gases in.) We always ship our coffee to our mail order customers within days of roasting it in small batches, so the coffee you receive will be nice and fresh. After that, it’s up to you to brew and drink your coffee before it goes stale.
What if my Light or Medium Roast Coffee Beans are Oily?
This is typically an indication that your coffee beans have been sitting, exposed to oxygen for longer. They are still usable, but you may not get the best and strongest flavor from them. We recommend trying to use your coffee within three to six months from ordering, and storing coffee in an airtight container (or in an airtight container in the freezer) in the meantime.
