It’s critical to distinguish between “good bitter” and “poor bitter.” Good bitterness is present in dark roast coffee and is caused by chemical elements such as caffeine and acidity. These often impart a deep, dark, or somewhat lemony flavor to your cup of Joe.
Bad bitter taste, such as discarded matchheads, coal, or old coins. These unpleasant tastes can be generated by over-roasted beans during processing or by using a subpar coffee machine.