Barista Boaz Bosboom van Screaming Beans in Amsterdam was maandagmiddag te gast bij Omroep Max op Nederland 2. Boaz gaf een mini-college over koffie. In dit fragment geeft Boaz zijn visie over cafeïne bij espresso en filterkoffie.
One of the most commonly asked question we receive is: "is it true that espresso coffee has more caffeine than regular drip coffee? "
Ask almost anyone and they will invariably say that espresso has more caffeine than regular coffee. I mean it makes perfect sense, what else would explain that caffeine buzz we get when we down a shot of Starbucks espresso in the morning?
Interesting, but is this correct? Well that depends on your perspective.
During the 1950's a typical serving size of coffee ranged from 4 to 6 oz - though in recent years our "cup" size has grown significantly ranging from about 6oz to anywhere up to 24oz.
According to the National Coffee Association (NCA) a typical cup of drip coffee (8oz) contains approximately 65-120 mg of caffeine.
Why such the large variation in caffeine?
Well without getting overly technical, there are several factors including brew time, dwell time, water temperature, grind level, roast level, bean type, blend, etc. that all have a significant affect on the final extraction of caffeine. We'll discuss those a bit later.
What has more caffeine - espresso or regular drip coffee?
If we look at published data - its clear that a cup of drip coffee (100mg on average) contains much MORE caffeine than a shot of espresso (30-50mg).
But how much more? Well, about 2-3 times more than espresso!
So is this is shut case?
No, not exactly!! Its actually an unfair comparison and need to compare "apples to apples".
To accurately make a comparison between the two, we need to compare concentrations in terms of caffeine per ouce (oz).
In the case of drip coffee, we divide the 65-120mg of caffeine by its serving size - in this case 8 oz - - resulting in: 8.125 - 15 mg per oz.
That means that for every once of coffee solution, you can expect 8.125-15mg of caffeine.
Whereas in espresso, even though we start off with about a 1/2 to 1/3 LESS caffeine (ie. 30-50mg) - all this caffeine is contained in just 1oz of liquid or expressed numerically as 30 - 50mg per oz.
Meaning that in in just 1oz of espresso solution, we can expect 30-50mg of caffeine.
So what does all this mean?
Although we can conclude that drip coffee contains much more caffeine than espresso - this is all due to its much larger serving size - 8oz vs 1oz.
Obviously since espresso is served in much smaller volumes, we see less caffeine (from a beverage perspective).
BUT when viewed from a volume perspective - espresso has a much more caffeine than drip coffee.
Okay, so what has more caffeine drip or espresso?
Well the answer really depends on your perspective...since both are correct!!
From a beverage perspective - drip coffee has more caffeine.
From a volume perspective - espresso has more.
Comparison of Caffeine Content in Drip Coffee vs Espresso*
65-200mg of caffeine/8 fl oz
(8.125-15mg/1 fl oz)
30-50mg/1 fl oz
(30-50mg/ 1 fl oz)
* bold numbers are in a beverage perspective, numbers in parenthesis are from a volume perspective.
So why do most people believe espresso has more caffeine than regular?
Well, part of the reason this belief has continued to exist is because caffeine itself an intensely bitter compound. Since espresso coffee is roasted much darker than drip coffee - and darker roasts create compounds which are much more bitter - the "connection" between more caffeine and espresso is made. But this is incorrect.
The bitter compounds that arise in darker roasts is not due to more caffeine, but rather bitter compounds created during the Maillard reaction.
It is this much lower concentration of caffeine (per serving) in espresso that allow Italians to drink upwards of 10 to 12 espresso's per day without getting overly jittery - consuming an equivalent amount of drip would be quite impossible.
Unfortunately its very difficult to "standardize" the caffeine of coffee beverages since there are numerous variables need to be considered, including:
Beverage Size - is a cup 4oz, 5 oz or 12oz ??
Blends - many roaster create their own blends of various beans each with subtle difference in caffeine content.
Bean Type - is the blend 100% arabica, robusta or both?
Grind - was the coffee prepared with a fine grind, ultra fine grind, coarse, etc?
Water Temp - was the coffee prepared with the recommended 195-205F temperature range?
Milk - was milk added or now - as this will dilute the caffeine content per ml.
Others - machine type, dwell time, etc.
All these factors make the calculation of caffeine in most common beverages a challenge. Hopefully with the implementation of industry standards by organizations such as the SCAA and NCA - we can begin the journey towards creating baselines on caffeine for each of these products.
1. Caffeine Content of Common Foods and Beverages. Coffee Update, August, 1999. National Coffee Association of USA (www.coffeescience.org