Did you know that the amount of caffeine present in a cup of coffee depends on multiple factors?
The amount of caffeine present in a cup of coffee depends on multiple factors. Make sure you read the last factor - it is a total "Myth Buster".
1) The brewing method. Different preparation methods for coffee yield different levels of caffeine extraction. A cup of espresso though smaller might contain as much as twice or more the amount of caffeine per ounce than drip coffee. This explains the “kick” one gets from this smaller cup of coffee. For every ounce, espresso has about 40–55 mg of caffeine. Drip has only 9–18 mg of caffeine per ounce. This means that an average 8 oz. drip coffee has between 70–140 mg of caffeine, whereas a shot of espresso (about 1.5 oz.) has between 60–80 mg of caffeine.
2) Extraction time. The longer you let your coffee to extract the more caffeine will be extracted.
3) The type of coffee bean used for the coffee extraction. Only two kind of coffee beans are used world wide, the Arabica and Robusta coffee beans. They the kind of beans you use will have a great effect on the amount of caffeine present in your daily cup of Joe. Popular Arabica beans contain about 1.5% caffeine whereas the Robusta kind contains about 2.5% of caffeine.
4) How fine your coffee ground is. The finer your coffee ground is the more surface are there is which means there is more surface area for more caffeine to get extracted.
5) Serving size. This one is obvious – how big are your 3 cups of daily coffee? "One cup of coffee" can range anywhere from 30–700 ml (1–24 oz), greatly affecting the total caffeine content.
6) Extraction Temperature. 195-205 degrees yields the best caffeine extraction. This will ensure that you can stay all night awake to enjoy your coffee.
7) One thing that will NOT affect your caffeine intake is choosing a lighter roast to a darker roast. If anything this is the opposite. Darker coffee beans (french roast) does not actually have a higher content of caffeine. The perceived association of darker roast with higher content of caffeine largely comes from people mistakenly associating caffeine levels with flavor. Though it is true that caffeine is a bitter substance, the bold flavors of dark roasts come from the roasting process itself and not from the caffeine level.
In fact, there is a very little effect on the level of caffeine caused by the roasting process (assuming one does not burn the bean). Though more caffeine is burnt during the roasting process resulting in darker colored beans having less caffeine. The burn-off is of little change with almost an equal amount of caffeine for both light and darker beans.