Coffee – Caffeine Content

Posted on: January 2nd, 2013 by admin No Comments

One of the most commonly asked questions is how much more caffeine is contained in espresso versus brewed coffee. The answer isn’t complex but is solely dependent on your perspective.

In the US, a typical serving size for brewed coffee ranges anywhere from 8-16 oz. respectively containing 90-150mg of caffeine per cup 8oz.

The large range in caffeine content is due to factors such as brew time, dwell time, water temperature, grind level, roast level, water temperature, bean species and blend. all have a significant effect on final caffeine extraction. Compare this to a shot of espresso containing anywhere from 30-50mg of caffeine per oz. and the difference is significant.

Clearly a cup of brewed coffee has anywhere from 3-10 times more caffeine than espresso – but if to accurately make a comparison between the caffeine content, we need to compare concentrations in terms of caffeine per fluid ounce. This can be achieved by dividing the caffeine in 8 oz. of brewed coffee its distributed in – resulting in caffeine mg per oz. Whereas in espresso, even though we start off with about a third of the caffeine, it’s all contained in just 1oz of liquid or 30–50mg/oz.

So although brewed coffee contains much more caffeine than espresso as consumed, viewed from a volume perspective espresso has a higher caffeine level per volume.

So why do most people believe espresso has more caffeine than regular?

Well, part of the reason is because, in its native form, pure crystalline caffeine is intensely bitter. The compound is so bitter that it is commonly used as the “reference” compound for bitterness detection. Coincidentally, espresso is also very bitter and people tend to associate this for increased caffeine concentration.   But actually, the majority of the bitter compounds are not attributed to caffeine but rather to a myriad of by products produced during the roasting process, namely the Maillard reactions.

It is this much lower concentration of caffeine per serving in espresso that allow espresso lovers worldwide to drink multiple espresso’s a day without getting overly jittery.