Has Chromatography Found the World's Strongest Coffee?

Do you like your coffee strong? How strong is strong though? Using the caffeine content of the coffee is one method of measuring strength — after all it is the coffee’s ability to give a kick that many of us use to determine how strong a brew is.

Finding the right beans is the key to getting strong coffee and now a blogger — from Cape Town’s Best Coffee blog — has decided to find the World’s Strongest Coffee. Using a scientific approach and latest analytical techniques he has found which coffee we should all be using in the morning to make sure we are all ‘bright-eyed and bushy-tailed’ for the commute into work.

It’s in the beans

The blog decided that the best method of determining a coffee’s strength was to use the caffeine content of coffee beans. Coffee shops might claim that they are making strong brews — but that is using brewing method to produce a stronger coffee, and if the strongest beans were put through the same process there is every reason to suspect that they would produce the stronger coffee.

There are two main varietals of beans used to produce the coffee we drink — Arabica beans and Robusta beans. Arabica beans are used to produce about 70% of the world’s coffee. They give a mild aromatic coffee and are the beans you are likely to find in your local coffee house.

Robusta beans are used in blends and instant coffee and are cheaper to produce than Arabica beans. But key to this discussion, they have a higher caffeine content than Arabica beans — with Arabica beans having a caffeine content of 1.5% and Robusta beans around 2.7%. But this increased caffeine content affects the flavour with caffeine having a bitter taste.

A cup of Black Insomnia will wake you up

The blog obtained samples of three coffees that claim to be strong and sent them to an accredited laboratory for caffeine content analysis. The laboratory used High Performance Liquid Chromatography (HPLC) to separate, identify and quantify the compounds in each bean —with the focus on caffeine content.

The results indicate that Black Insomnia had the highest caffeine content (17.5 g/Kg) at approximately 33% more caffeine than its nearest competitors and significantly more than a Starbucks Dark Roast (5 g/Kg). The coffee is a mix of Robusta and Arabica beans, and reports are that it tastes just fine. But with the maximum caffeine consumption per day at 400 mg, you are only allowed one cup of Black Insomnia per day.

Chromatography isn’t only used to analyse legal substances, take a look at this article to discover how scientists analyse illegal highs, Tackling the chromatographic analysis of novel psychoactive substances with High Resolution Mass Spectrometry.