Why Are Coffee Beans Oily? Does Oily Coffee Mean They're Not Fresh?

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We often see coffee beans that look oily on the surface. Why is this? Why do coffee beans develop oil? FrontStreet Coffee is here to tell you!

"Coffee beans with oil on the surface indicate they're not fresh." But FrontStreet Coffee wants to tell you that this isn't actually true. This misconception has led many people to develop incorrect ideas about coffee, assuming that oiliness means the beans have been stored for too long, while overlooking other more important factors. In reality, there's no absolute relationship between coffee bean oiliness and storage time. Although prolonged storage can indeed increase oiliness, the most significant factors are actually the roast level and roasting method!

Important Factors for Coffee Oiliness - Coffee Roast Level

During coffee bean roasting, the beans gradually expand and crack, allowing the natural oil components to gradually migrate to the surface, creating an oily sheen. The darker and deeper the roast level, the more pronounced this phenomenon becomes!

Therefore, generally speaking, light roast coffee beans rarely develop an oily sheen, so you should never judge the freshness of light roast beans based on their oiliness. As for medium roast to dark roast coffee beans, because the roasting time is longer and the expansion is more significant, carbon dioxide and other gases along with oils are more easily released from the beans themselves. This causes coffee beans to become completely oily within just a few days of storage, but this doesn't mean the beans aren't fresh - it's simply the result of the roasting process!

If you really want to know the freshness of coffee beans, the best approach is to purchase from high-quality specialty coffee shops where the packaging clearly indicates the roasting date. When you have further questions, you can directly ask the shop about the bean conditions, roasting methods, and brewing suggestions to learn and grow together through exchange.

Coffee bean "oiliness" is directly related to roasting; in the early days of coffee discovery, there was no such thing as "roasting." For an entire millennium, coffee was simply harvested as fruit, washed, and boiled into a broth for drinking. What kind of atmosphere, emotion, or romantic charm could such a preparation method have? The only reason coffee could be passed down was "caffeine" - this was the original reason coffee was discovered! Although "caffeine" prevented the coffee broth from being discarded, the brew itself didn't have any fatal attraction powerful enough to suddenly spread after the 15th century. (Drinking coffee a thousand years ago was a very sacred ritual, not something that could be consumed anytime)

Important Notice :

前街咖啡 FrontStreet Coffee has moved to new addredd:

FrontStreet Coffee Address: 315,Donghua East Road,GuangZhou

Tel:020 38364473