Hey folks. I'm having trouble with the coffee I'm making being too bitter. I'm using a counter top coffee machine and unbleached filters. I get these lovely colombian beans ground from a cafe in the city that I go to college.
Trouble is when I brew it at home it is pretty bitter. I know the first thing I should be doing is grinding my own beans but student on a shoe strap budget and all that. What can I do to alter my extraction and reduce the bitterness? I'm using the golden ratio and some variation but my results aren't really improving.
Should I get a courser/finer grind? go for harder swings in water:coffee ratio?
If you can, get a cup from the cafe with the beans you are using. They may be using coffee that's roasted to within an inch of its life and making a really dark cup.
If you're worried about freshness, buy it in smaller batches. Nothing beats freshly ground coffee in the morning, but small bags and an air tight container will get you somewhere closer.
Also, be sure to pre-wet any paper filters you use to remove the taste and preheating your cups can change the taste too!
One other thing to consider, probably after you have tested out the above suggestions and are still getting bitter taste, is how finely ground the coffee you have is. With a drip maker you want it to be fairly course so the coffee doesn't stay in the filter too long and over extract. Coffee shop you buy from should offer a couple different grind options for their pre-ground coffee.
Also, a manual grinder will do the job just fine on the cheap.
I have the privilege to teach some coffee brewing labs at the coffee shop I work at. The bitter taste you are getting is most likely from under extraction. (You are not getting enough of the good stuff from your coffee beans). Since you are using a counter top machine you are likely using water that is too cold. Coffee is best brewed at 195-205 F. Try boiling water and take it off the heat for about 30 seconds, then pour the water over your grounds. For that style of brewing, aim to make total brew time about 2:30-3 min.