Coffee

Coffee pot

Instant facts

We couldn't make Open2 without it - and it has a fascinating history. Discover more about coffee.

Gentle nudges

They're only tiny, but they can cause massive changes in our lives: find out how molecules affect us.

Take a look what's really in that morning pick me up cup of coffee

Fancy a cuppa? Carbohydrates and acids give coffee its quality and flavour. Pyruvic acid has that burnt caramel flavour and 2-Methylvaleric acid gives a cocoa-like taste. The bitterness is trigonelline, which contains nitrogen, partially converted to niacin during roasting. But probably the most well known component of coffee is caffeine (C₈H₁₀O₂N₄).

Your cup of coffee has between 50 and 125 mg of caffeine per cup. Caffeine is addictive, if you habitually drink 2 cups a day, then stop, you may experience withdrawal symptoms - headaches, fatigue and irritability.

Caffeine is an alkaloid, a stimulant that increases blood pressure. It’s also a diuretic, causing the body to lose essential vitamins and elements, such as calcium, sodium and potassium. There are over 800 known compounds that make up the aroma of coffee.

Furans are the most predominant group of compounds, which react with sulphur compounds to create the caramel smell. The roasted walnut/cereal smell comes from the second most abundant group, the pyrazines. The pyrroles produce the sweet, caramel-like and mushroom-like aromas. Thiophens, which also have a presence in the aroma of coffee, have a meaty aroma, and thiazoles play a small part in the overall coffee smell.

Content last updated: 14/02/2005