Bitter coffee is commonly caused by over-extraction, where too much is extracted from the coffee grounds during brewing. An overly fine grind, excessive brewing time, high temperature, dark-roasted beans or a dirty brewing system can all contribute to an unpleasant bitter taste.

Yes. If the grind is too fine, water passes through the coffee more slowly and can extract more bitter compounds. If your coffee is dispensing very slowly as well as tasting bitter, try adjusting the grinder slightly coarser. Make small adjustments and allow several coffees before judging the result.

Yes. A high strength or aroma setting generally increases the amount of ground coffee used for the drink. Combined with other settings, this can produce a stronger or more intense flavour than you prefer. Try reducing the strength by one level and compare the result before making further adjustments.

The beans may have changed or the brewing system may need cleaning. Different beans and roast levels can taste considerably different using identical machine settings, while old coffee oils accumulating around the brewer and coffee outlets can introduce stale or bitter flavours. Try fresh beans and clean the brewing system before making major adjustments.

Yes. Higher brewing temperatures can increase extraction and emphasise bitter flavours, particularly with darker-roasted coffee. If your machine has adjustable temperature settings, reducing the temperature slightly may produce a smoother cup. Change one setting at a time so you can identify what actually improves the flavour.

Yes. Coffee oils and residue gradually accumulate within the brewer and coffee path. These deposits can become stale and negatively affect the flavour of freshly brewed coffee. Regular brewer and coffee-system cleaning helps prevent old residue from influencing the taste of your drinks.