“Why Is My Espresso Bitter? 5 Common Culprits and How to Fix Them”

By bobbreich@gmail.com •  Updated: 11/30/23 •  5 min read

Why Is My Espresso Bitter? 5 Common Culprits and How to Fix Them


Making a good espresso is an art form that requires precision and attention to detail. However, even the most experienced baristas sometimes struggle with bitter espresso. If you’ve ever wondered why your espresso is bitter, this blog post will explore the common culprits behind this unpleasant taste and provide you with tips on how to fix them.

Understanding the basics of espresso

Espresso is a concentrated form of coffee that is brewed by forcing hot water through finely ground coffee beans under high pressure. The process extracts the flavors and oils from the coffee beans, resulting in a rich and intense beverage.

There are several key components that contribute to the flavor profile of espresso, including the type of coffee beans used, grind size, extraction time, water temperature, and water quality. Each of these factors plays a crucial role in determining whether your espresso will be smooth and balanced or bitter.

Common culprits of bitter espresso

1. Low-quality coffee beans
Low-quality coffee beans can significantly impact the taste of your espresso. These beans are often poorly processed or roasted unevenly, leading to a bitter flavor. To ensure a better-tasting brew, opt for high-quality beans that have been freshly roasted and properly stored. Look for specialty coffee shops or reputable online retailers that offer single-origin or freshly blended coffees.

2. Incorrect grind size
The grind size directly affects how quickly water extracts soluble solids from the coffee beans during brewing. If your grind size is too fine, it can result in over-extraction and bitterness. On the other hand, if it’s too coarse, under-extraction may occur, leading to a sour taste.

To achieve optimal results, experiment with different grind sizes until you find the right one for your machine or brewing method. Generally speaking, finer grinds are suitable for shorter extraction times such as those used in espresso machines. Invest in a quality burr grinder to ensure consistent grind size.

3. Over-extraction
Over-extraction occurs when water comes into contact with the coffee grounds for too long or with too much pressure. This prolonged contact causes an excessive extraction of bitter compounds, resulting in a bitter taste.

To prevent over-extraction, consider adjusting your brew time or using different distribution techniques to ensure an even extraction. Additionally, make sure to use fresh coffee grounds for each shot to prevent over-extracted flavors from previous brews contaminating the current one.

4. Too much coffee dosage
Using excessive amounts of coffee can lead to a stronger and more bitter-tasting espresso. It’s important to find the right balance between coffee-to-water ratio for optimal extraction and flavor.

For a standard double shot of espresso, aim for around 18-20 grams of coffee. Use a scale to measure your dosage accurately and experiment with different amounts until you find your preferred taste profile.

5. Inadequate brewing temperature
The brewing temperature plays a crucial role in extracting the flavors from the coffee beans. If the temperature is too low, under-extraction can occur, resulting in sourness. Conversely, if it’s too high, over-extraction may happen, leading to bitterness.

Ideally, aim for a brewing temperature between 195-205°F (90-96°C). Make sure your espresso machine is properly calibrated and maintain it regularly to ensure consistent water temperature during brewing.

6. Unsuitable water quality
Water quality significantly impacts the taste of your espresso. Hard water with high mineral content can result in off-flavors and affect extraction efficiency. On the other hand, using distilled or overly filtered water can lead to dull and flat-tasting espresso due to lack of minerals necessary for flavor development.

To achieve optimum results, use filtered water that has balanced mineral content suitable for making espresso. You can also consider using specialized water products designed specifically for espresso brewing.

Tips and techniques to fix bitter flavors in espresso

1. Adjusting brew time
If your espresso is consistently bitter, try adjusting the brew time by slightly increasing or decreasing it. Even a few seconds can make a noticeable difference in the flavor profile.

2. Improving extraction with distribution techniques
Uneven coffee distribution can lead to inconsistent extraction, which may result in bitterness. Experiment with different distribution techniques such as leveling, tapping, or using a distribution tool to ensure an even bed of coffee grounds before brewing.


Making a good espresso requires attention to detail and understanding how various factors affect its taste profile. By avoiding low-quality beans, adjusting grind size, preventing over-extraction and using appropriate coffee dosage and water quality, you can significantly improve the flavor of your espresso. Remember, it’s important to invest in quality ingredients such as freshly roasted beans and properly calibrated equipment to achieve the best results possible. So next time you find yourself wondering why your espresso is bitter, refer back to this blog post for troubleshooting tips and techniques that will help you enjoy a smooth and flavorful cup of espresso every time.