Caffeine content in coffee
Coffee naturally contains varying amounts of caffeine. Robusta coffee beans (1.7 - 4 %) have about twice as much caffeine as Arabica coffee beans (0.8 - 1.4 %).
Different levels of coffee grinding, coffee brewing methods and different levels of coffee roasters are factors influencing coffee caffeine content.
A balanced nutrition program will also affect the caffeine content in coffee.
Magnesium
Magnesium has a positive influence on caffeine content of the coffee bean.
Sulfur
Using appropriate levels of sulfur will also improve the caffeine content of coffee.