Because when you prepare espressos the water passes through the coffee very quickly, the beans need to be ground finely so that the compounds can be absorbed easily. Generally the longer coffee comes into contact with the water, the greater the absorption and greater the strength. Grinding breaks down the coffee cells, allowing us to dissolve more compounds, creating the flavour. The biggest differences come from how the coffee is prepared (espresso, drip, French press…) and how finely ground the coffee bean is. How Brewing Impacts a Coffee’s Caffeine ContentĮvery step of transforming the roasted coffee bean into a drink directly impacts on its strength – the quantity, tamping, water temperature, water pressure, water/coffee ratio and extraction rate. There are so many subspecies of coffee varieties though, that the vast majority have not been compared and there is no accurate way of ascertaining a coffees strength by region alone. Ugandan Robusta coffee has more caffeine that the same species in Vietnam and similarly some Brazilian Arabica subspecies contains more caffeine then Ethiopian, Mexican or Kenyan varieties. However most coffees are regional blends, reducing the variation from bag to bag and instead creating broader differences from region to region. The level of light, altitude, soil composition and health of the bush all impact on the caffeine content of the bean, so there is variance even within fields.

How a Coffee Bean’s Origin Impacts How Much Caffeine Is In The Coffee While roasting time has a minimal impact, during roasting coffee beans expand and lose weight, reducing their density, so if a coffee serving is measured using a scoop, instead of by weight, the stronger the coffee roast, the weaker the coffee. Otherwise the main factors in a coffee’s caffeine strength is the bean’s origin, how coarsely it’s ground, the brewing method and the serving size. Its caffeine content ranges between 1.2 and 2.4% of dry weight compared to between 0.9 and 1.5% for Arabica, so know which type you’re drinking as 0.9 or 2.4% is a huge difference. The Robusta bean is far stronger than the Arabica and has a greater variance in strength. The biggest difference though is the bean itself. What Determines The Caffeine Content Of Coffee?įrom bush to belly nearly every step in a coffee bean’s journey impacts on the coffees caffeine strength. If you are going to drink a coffee pre-race it is therefore vital to understand exactly how strong your coffee is and to learn what determines a coffee’s strength. Overly strong coffee before a long race will lead to you starting too quickly, increasing your chance of crashing and will diminish the impact of additional caffeine later in the race.

Weak coffee before a short race will deny you of the caffeine boost you’ve come to rely on and the more arduous start could play on your mind and affect your pacing.Hopefully the impact on our daily life is relatively insignificant, however if a strong cup of coffee is part of your pre-race routine it could jeopardise your entire race: So depending on the day, your coffee could be over twice as strong. Think you know? If so what do you think the caffeine content of a standard cup of coffee is, does it matter?Ī 2014 study found that a 200ml cup of regular black drip coffee can have anywhere from 75-150 mg of caffeine, while a six-day analysis of Starbucks’ speciality coffee varied between 259 and 564mg caffeine per 473ml cup.

Mg caffeine in coffee