As the question asks, which method from the list below will give the most caffeine in the final product (ie. a cup of coffee). Assume the same beans with the same grind (while the different techniques should use different grinds, lets try and keep things simple) and as much as possible assume things are kept constant – Aiming for a 200ml cup of coffee made from (if appropriate) a double shot of espresso, the rest made up by water. :
- Professional Espresso maker (i.e. in a coffee shop)
- Aeropress
- Stovetop espresso maker
- French Press
- Consumer grade capsule coffee machine (e.g. nespresso). Once again assume that we can find the same bean in a bought capsule.
Best Answer
This question is nearly unanswerable. Typical caffeine content data is given as a range based on the normal brewing factors of each method, there isn't data for abnormal methods i.e. french press with fine grind or espresso with coarse grind.
Typical caffeine contents:
On average the espresso or moka pot coffee would have significantly higher caffeine concentration than other methods (with the moka pot maybe edging out the espresso because it uses higher temperature for extraction). There is so much variability that I don't know if there's any point in trying to answer this question. The article linked below shows that one method alone (espresso) can yield shots with caffeine concentrations that are radically different:
If you control for volume by diluting everything with a typical serving size less than 200mL, all the methods are going to yield caffeine doses in the range of 60-100mg. A typical espresso based Americano (1 shot + water to make 5oz) would also fall in that range.
http://www.aseanfood.info/Articles/11020406.pdf