New Study Reveals Another Factor Behind Coffee’s Bitterness

A recent study published in Food Chemistry has identified a new factor influencing coffee’s bitter taste: mozambioside and its by-products formed during roasting. Researchers at the Leibniz Institute for Food Systems Biology at the Technical University of Munich found that these compounds play a key role in shaping the coffee’s flavor.

Roasting and the Science of Bitterness

For a long time, caffeine was considered the main source of coffee’s bitterness. However, this study highlights another important contributor: mozambioside. This compound, present in raw Arabica coffee beans, breaks down during roasting into several new substances, some of which have an even stronger bitter taste than caffeine.

Using advanced testing methods, researchers tracked how mozambioside changes during roasting. They found that the level of bitterness depends on the roasting temperature and duration, with the strongest bitterness forming at temperatures between 240 and 260°C. Among the new substances formed, some were identified as key contributors to coffee’s bitter flavor.

How Does This Affect Coffee Drinkers?

Taste tests confirmed that these bitter compounds interact with specific taste receptors in the human body. Interestingly, some people are more sensitive to these compounds than others due to genetic differences. About 20% of Europeans, for example, have a genetic variation that makes them less sensitive to coffee’s bitterness.

Additionally, nearly all these bitter compounds dissolve into coffee when it is brewed, regardless of the brewing method. This means that whether you drink espresso, filter coffee, or another preparation, you are likely consuming these bitterness-enhancing substances.

Implications for the Coffee Industry

This discovery could help coffee roasters fine-tune their roasting techniques to control bitterness. By adjusting roasting conditions, they could create different flavor profiles to match consumer preferences. The study also opens the door for further research into how personal genetics influence the way people experience coffee.

Conclusion

This study provides new insights into why coffee tastes bitter, highlighting the role of mozambioside and its breakdown products. These findings could lead to new innovations in coffee roasting and brewing, helping both coffee producers and consumers better understand and manage coffee’s flavor.

For coffee lovers, this research adds a deeper appreciation for the complexity behind every cup, showing that the taste of coffee is shaped not just by caffeine but by a range of other naturally occurring compounds.