Skip to main content

A combination of media has bought the subject of caffeine to the fore over the last few weeks. Firstly James Hoffmann did a tour of specialty coffee shops in London and found some consistent and stable results. This is amazing in some ways if we look at it from an ingredients perspective. After this JH then went to a number of High Street chains and found some wildly different results. The question this begs is how much ingredients, roast, and dose change this.

When the phone started to ring about this I knew this wasn’t going to be an easy one to answer and break down, but let’s see where this goes.

What is Caffeine?

Funny how when you first start looking for what caffeine is, it is all about what it does to humans. Let’s pretend that you haven’t looked at the headlines on Google.  Caffeine is a stimulant to the central nervous system of humans. Maybe we should ask the question …

Why (as in What is the point of) Caffeine then?

At the bottom of a lengthy article by the New York Times in 2014…” When coffee leaves die and fall to the ground, they contaminate the soil with caffeine, which makes it difficult for other plants to germinate. Coffee may thus use caffeine to kill off the competition. Coffee plants also use caffeine to ward off insects that would otherwise feast on their leaves and beans. At high doses, caffeine can be toxic to insects. As a result, insects have evolved taste receptors that help them avoid ingesting caffeine.”

Caffeine is common in a number of other plants, including tea and cocoa. Randomly Walnuts do something similar, creating a chemical called Juglone. That could look made up, from walnuts’ Latin name Juglans, if it was, not by me.

To sum up, Caffeine is a toxin, created by plants to protect themselves.

How important is it to know?

This is where it’s great to be “lazy” and short of buying a caffeine meter and navigating my way around many coffee shops and “joining in”, this is what has been in the media over the last few days.

James Hoffmann visits 5 Independent Coffee shops and 5 chains. The ranges of the specialty shops were: 110-135mg and the chains varied between 85 and 179mg. Crowds love chains because the theory is that you always get consistency. But do you? How does it go(?) Same stuff, different day.

Which? joined in and got delivery of their new caffeine meter. However, in measuring the amounts of Caffeine, I would suggest the JH has an 18-year head start on them and knows his oats. Although Which? did extrapolate some big numbers, if you compare it to James’, you will see a pattern, just that the numbers were bigger, but in a similar order. With Which? they quoted that coffee from Costa Coffee had up to 325 mg of caffeine. I was wondering if this was a little like measuring alcohol after a few hearty drinks or measuring coffees with different amounts of milk, rather than just the weight of coffee and water.

In specialty coffee, things have become homogenous and many companies follow the same recipe for brewing, similar coffees in season (insert small world pun), and safe similar roast levels. Could this be the reason for a range of 20% between them?

Chain coffee is different. Famously Starbucks is very dark, compared to specialty. Possibly less coffee is used when it is this dark and (as I remember) is typically out of Super-Automatic machines and these can use as little as 8-10g of coffee. If we compare this to a traditional machine in independents the UK, most are using a standard recipe of 17g into 30-something grams. More roast isn’t necessarily more caffeine either.

Stepping outside rights and wrongs, we have two main areas of caffeine sources or spikes. You will most likely have heard of the two most known species of coffee: Arabica and Robusta. The former is (typically) higher-grown and has many varietals and can be the most delicate drink under the sun, the latter is (broadly speaking) great for the body in a cup of coffee and has relative ease of cultivation. Robusta or Coffea Canophera, (if you really want to know how restricted my Latin is) is naturally higher in caffeine than arabica. Altitude and soil also play a part too, but not to the same extent. There is no point in me throwing out baseless numbers.

If I step outside my own bias, JH found that 3 of the chains were within 20% and 4 if you were being generous. It was actually just that Costa Coffee seems to be higher at the moment, by findings of Which? too, in my understanding. Maybe they are using coffees that are higher in caffeine at the moment? They also use traditional espresso machines, so they could well be using more coffee too. I am just reading the facts from a step back.

Thanks for asking the question about this. I hope that this is a rounded way of answering the question.

For the record, I would pick coffee from a specialty independent coffee shop over a chain all day long, every day.  Without small businesses, there is no longer variety amongst other good things.


Let me know if I am way out and if I should barricade the doors before the lawyers come.

Thanks for reading.