Like many coffee lovers, the Presto team are big fans of caffeine. But after a team chat, we all began thinking, what actually is caffeine and how much is found in our beloved beverage? As always, we reached out to our roasters for a little guidance and information.
What is Caffeine?
Caffeine is a natural stimulant, which can be found in plant based foods and drinks, like coffee, tea, chocolate, cola and guarana. Caffeine typically boosts our alertness and energy levels, though it affects everyone differently, with some people being very sensitive to it, whilst others notice very few effects. Caffeine typically boosts our alertness and energy levels.
Caffeine in its raw form is a white powder that is bitter to taste, the chemical name is 1,3,7 trimethylxanthine. It typically takes about 45 minutes to be absorbed into the bloodstream, but you can notice the effects from 15 minutes. Caffeine from drinks is quickly absorbed, whereas that from solid foods can be slower to absorb. That means drinking your morning espresso on an empty stomach will give you a quick caffeine hit then after breakfast.
Caffeine is broken down mainly by the liver and can remain in the bloodstream for 1.5 to 9.5 hours.
The amount of caffeine per coffee can vary widely depending on roast profile, brew type and variety of coffee, but it is widely accepted that for 400mg of caffeine per day is a recommended daily maximum for healthy adults (200mg for pregnant women), 400mg being equivalent to about four mugs of coffee.
A typical espresso coffee coffee will have about 50-65mg (per ounce/28g) and a normal cup of filter coffee about 12-14mg of caffeine (per ounce/28g), but your normal filter coffee might be 150-200ml, meaning the total amount of caffeine per mug can be 100mg.
Arabica vs Robusta Coffee
Robusta coffee beans have on average 83% more caffeine than arabica beans, so making coffee with these beans will produce a cup of coffee with 83% more caffeine. So a robusta espresso could have 120mg, and a mug of robusta filter could be 200mg of caffeine.
What about caffeine in decaf coffee?
As you would expect decaf coffee contains a lot less caffeine, but not zero. One study found that decaf servings contained between 3-15mg of caffeine for the typical mug. That means that if your doctor has told you to avoid caffeine altogether then decaf unfortunately isn’t for you. That said black tea contains 47mg of caffeine and green tea 33mg per mug, so decaf is relatively ‘caffeine light’ and could help you lower your intake to a level that works for your tolerance
There are a few methods for decaffeinating coffee and each of these has an impact on the caffeine levels and end flavour profile of the coffee you drink.
What about caffeine in other foods and drinks?
- 50-65mg per espresso of arabica (for example: our Espresso Roast)
- 100-120mg per espresso of robusta (for example: our Rocket Roast)
- 100mg per mug of coffee (arabica)
- 180-200mg per mug of coffee (robusta)
- 3-15mg in decaf coffee
- 47mg black tea
- 33mg in green tea
- 55mg in a Coca Cola
- 24mg in 1 ounce of dark chocolate
- Caffeine supplement tablets - 200mg
Coffee and Exercise
Cyclists are particularly fond of strong coffee due to the performancing enhancing boost it gives, particularly for endurance. Caffeine was actually placed on the World Anti-Doping Agency’s (WADA) banned list in 1984 and remained there until 2004 when it was removed.
Caffeine is known to bind with the receptors for adenosine. Adenosine promotes muscle relaxation, sleepiness, and blocks dopamine. This is the cause of many of caffeine’s more typical effects such as increased heart rate, blood pressure, alertness, and also is one of the things that helps with performance enhancement.
How much do I need to help with exercise?
In short quite a lot! When studied by sports scientists, the recommended amount is 3-6mg per KG of body weight. So for an average male of 75kg that would be 225-400mg of caffeine - so at least 2-4 mugs of coffee. That said, if you are a regular coffee drinker you will build up a tolerance and therefore need more.