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Anyone can brew a great cup of coffee; all it takes is a sound understanding of chemistry at roughly an undergraduate level. For those of you who don't have the time to earn a four year degree but who want to enjoy some quality coffee, I offer you the "Cliff's Notes" version.

*Chemical Kinetics in the Aqueous Phase*

The rate of a chemical reaction approximately doubles for every ten-degree increase in temperature. Hence, coffee that is continually heated on a burner will degrade far more quickly than coffee stored in a thermal carafe. While both brews may maintain approximately the same average temperature all morning, their situations are not symmetric! The coffee in the carafe is maintained at a uniform temperature, while the coffee on the burner is heated to a high temperature on the bottom and allowed to cool at the top. The coffee that settles to the bottom overheats, decomposes, and gets transmogrified into the horrific substance knows as "gas station coffee".

Take home message? Buy a coffee maker that brews into a thermal carafe or simply transfer the whole pot to a carafe or thermos immediately after brewing it.

* Extractions and Partitioning*

The brewing process is simply the partitioning of the many substances that comprise coffee from the cellulose matrix of the bean to the water. The transfer takes place at the surface where water and bean meet, and thus by increasing that surface area, you will increase the rate of partitioning.

"Increasing the surface area" simply means grinding the beans to a finer powder. Using fine ground beans will result in a stronger cup of coffee. Espresso is made by grinding the coffee to a fine powder and pressing it to ensure that as much material as possible is extracted.

Surface area isn't the whole story, however.

As the compounds travel from bean to water, they change the composition of the liquid phase from "water" to the complex suspension/solution that is coffee. (Chemistry instructors may object to "suspension/solution" but in reality some compounds are dissolved while others are suspended, and the neither term in itself is sufficient to describe coffee.) Because the liquid phase has changed in character, so too does the rate of extraction. What's more, the various compounds extract at differing rates and are unevenly affected.

What does this mean for your morning cup of joe? It means there are two ways to control the strength of your coffee, and they are not equivalent. You can make a weaker brew by either grinding

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