Food - Drink
The Science Behind French Press Coffee
By ELIAS NASH
The way one brews their coffee is more than half the battle when it comes to a great cup. The French press appliance, which slowly steeps coarsely-ground coffee in water, is incredibly popular for its convenience and ability to brew a sweeter, full-bodied cup of joe; this is the science behind the success of the French press.
Coffee is a solution, a substance composed of solutes dissolved in water, and each soluble compound in coffee dissolves at a different rate. The way we add water to our coffee, and how long we keep that water in contact with the grounds, dictates which solutes are dissolved into our final cup and which are left behind.
Fruit acids and caffeine, which add flavor and energy to coffee, dissolve faster than carbohydrates and plant fibers, which add a bitter flavor. Drip and pour-over brewing methods, in which the coffee is exposed to a constant flow of hot water, can result in over-extraction, but the French press is much gentler.
The French press uses a "low and slow" steeping method that doesn't constantly add more water to the coffee grounds, which would dissolve more compounds and add more bitterness to your cup. Using a French press can keep less desirable compounds out of your coffee, resulting in distinctly sweet and smooth flavor.