Why Is My Coffee Bitter?
Dark roasts don't mean a bitter cup of coffee, but over-roasting does. Roasting is an art and many roasters don't know how to create a complex dark roast that has layers of flavor without overwhelming bitterness.
But assuming you start with properly roasted coffee, why is your coffee winding up bitter? The reasons generally fall into three categories.
First, you may be over-extracting the beans. This occurs when you leave coffee in a French press (it should be poured into a carafe after brewing) or when the grind is too fine for your brewing method.
Second, your equipment may not be cleaning. Residue will lend a bitter taste to your coffee, so clean your brewing equipment periodically with a solution of half water and half vinegar. Simply run it through the machine or pot and then run a second cycle of plain water.
Finally, your water may be partly to blame. Many municipal water supplies are chlorinated so your coffee could benefit from filtered water.
Here's to happy coffee-drinking!