Why is My Coffee Bitter?

Whether it's your first cup of the day or your last, there is nothing worse than a bitter tasting cup of coffee. Don't let bitter coffee ruin your day.

Even avid coffee consumers complain about the harsh taste of coffee from time to time. For people new to drinking coffee, adding sweeteners and syrups is a go to for removing the bitter taste, however you don't always need the extra additions to make your coffee less harsh. Discover our reasons why and tips that will help you say goodbye to bitter-tasting coffee.

Why Does My Coffee Taste Bitter

There are a couple of reasons why your coffee may end up tasting less than its best.

Over Extraction

Over extraction in coffee brewing occurs when there's too much contact time or too fine a grind is used, leading to excessive extraction of unwanted compounds from the coffee grounds. This includes bitter-tasting compounds such as tannins and chlorogenic acids.

When coffee is over extracted, these bitter compounds overpower the pleasant flavours, resulting in a bitter and harsh taste. Achieving the perfect balance of extraction is crucial in brewing coffee to highlight its desirable flavours while avoiding the bitterness that can ruin the overall taste experience.

Water Temperature

If the water temperature is too high, it can lead to bitter-tasting coffee. This is because it causes over extraction of undesirable compounds from the coffee grounds when water is too hot. High temperatures can extract more soluble solids from the coffee, creating an unbalanced and intense brew.

To avoid this, it's essential to use water within the optimal brewing range of 90 to 96 degrees, as this allows for proper extraction of the coffee's desirable flavours while minimising the extraction of bitterness.

Coffee beans

Low Quality Coffee Beans

Firstly, low-quality beans may be improperly processed or poorly sorted, leading to inconsistent roasting. Inconsistent roasting can result in uneven extraction during brewing, causing some parts of the coffee grounds to be over extracted and bitter, while others remain under extracted and lacking in flavour.

Secondly, low-quality beans might be old or stale, which can lead to the development of tainted and bitter flavours. Furthermore, these beans may have been exposed to unfavourable storage conditions, such as excessive moisture or light, which can negatively impact their flavour profile.

In contrast, high-quality coffee beans are carefully sourced, roasted, and stored to maintain their freshness and optimal flavour, resulting in a more balanced and enjoyable cup of coffee.

Brewing Method

Certain brewing methods, such as when making espresso or using a French press, can be more prone to bitterness if not carefully managed. In espresso brewing, over extraction can occur if the water passes through the coffee grounds too slowly or if the grind size is too fine, resulting in excessive extraction of bitter compounds.

Similarly, in a French press, the extended steeping time can lead to over extraction if the grind is too fine. On the other hand, using a drip coffee maker with the wrong water temperature or incorrect coffee-to-water ratio can also contribute to bitterness.

Understanding and mastering the nuances of each brewing method is essential to avoid bitterness and unlock the true flavours of the coffee beans.

Cleaning a coffee machine


Cleanliness is an often overlooked factor that can contribute to bitter-tasting coffee. When brewing equipment, such as coffee makers, grinders, or French presses, are not adequately cleaned, old coffee residues can accumulate and affect the flavour of the new brew.

These residues can become tainted over time, introducing unwanted bitter notes to the fresh coffee. Additionally, the buildup of oils and coffee particles on brewing surfaces can lead to inconsistent extraction, causing some parts of the coffee grounds to be over extracted and bitter while others remain under extracted.

Regularly cleaning and maintaining your coffee machine or equipment is essential to ensure a clean and fresh canvas for brewing, allowing the true flavours of the coffee beans to shine without any unwanted bitterness.

Remember that finding the perfect balance for your coffee might take some trial and error, so be patient and open to making adjustments along the way.

To find out even more about all-powerful coffee, see our article on the pros and cons of decaf and regular coffee.

Coffee shop

Coffee at Esquires

After many years of delivering outstanding products to our customers, it's fair to say we know a thing or two about great coffee and all the ways it can be enjoyed. While we've seen coffee trends come and go, we've kept our approach simple and no-nonsense - serving great-tasting, ethical coffee all day long!

You can be sure that every cup you enjoy at Esquires, a successful coffee franchise, is Fairtrade certified, organic and delivered with no compromise on quality, price or convenience. We apply artisan care to every stage of our coffee's journey, with immense respect for every bean we grind, pour and serve. So, with every sip, you can taste the love that's gone into it.