Why Your locally Roasted Coffee May be Bitter

For many connoisseurs, the taste and flavor of coffee is a critical part of experiencing the brew. Roasting coffee is a skill that is part science and part art form. Bitterness is one of the qualities that can ruin a cup of locally roasted coffee. In this article, we’ll be looking at why your drink may be bitter and what can be done to avoid it.

Compounds in Coffee Beans

The unique flavor and taste from coffee come from the compounds found in its berry. When preparing coffee, multiple chemical reactions can take place. The reactions can affect the taste of the coffee shops' final brew in different ways.

There are between 20 and 30 compounds that scientists believe can cause the bitter, harsh taste of coffee when brewing. Understanding the interactions between these compounds is important for specialty coffee brewers.

Despite a common misconception, caffeine is not the only compound that contributes to the bitterness. Caffeine only makes up about 15% of what sometimes gives the drink its harsh taste.

Types of Beans

Researchers have never been able to establish the exact number of compounds that are present in a berry. However, two types of chemicals can change the taste significantly. The chemicals are Phenylindanes and Chlorogenic acid lactones.

The Phenylindanes and Chlorogenic acid lactones are chemical compounds that are not present in green coffee beans. That is why coffee blends made with green tea usually do not have the harsh taste you’d find in other regular brews. Also, some methods of preparation, such as pressure extraction, can reduce the amounts of phenylindanes and chlorogenic acid lactones.

Overall, the type of bean will determine the unique chemical composition of your coffee. This is true even for specialty coffee, which accounts for 3% of global production.

Roasting Technique and Equipment

The preparation technique used can also influence the taste. For example, espresso in coffee shops is made through a process that involves a lot of heat and pressure. These two factors subject the beans to a chain of intense chemical reactions. A large number of compounds are activated, which can make the roasted coffee to have a flavor that is harsher than your regular brew.

The bitter taste can be managed by carefully watching the brewing process. For example, over-steeping can make your coffee blends extract more compounds saturating the brew. It also helps to ensure you use the right grinding setting for your brewing process. Very fine grinds are suitable for espresso machines used by coffee shops.

Last but not least, the other factor causing harsh taste could be the equipment’s cleanliness. You may rinse your coffee machine, but you could be skipping over the crooks and cranny. Watch out for the grooves and grains inside the filter cone in certain machines. You may clean the equipment with an acid-neutralizing agent like baking soda. Acidity may also be contributing to the bitterness.

Brewing coffee blends is a skill and an art that can be mastered. Specialty coffee brewers spend time researching the chemical composition and the best techniques for preparing the drink. For most consumers, the taste and flavor of coffee is an important part of the experience.