Coffee Chemistry: Cause of Bitter CoffeeCoffee bitterness is sometimes a negative, but omnipresent, aspect of the beverage. At low levels, bitterness helps tame coffee acidity and adds another favorable dimension to the brew. However, at high levels, a bitter coffee compound can overpower the other components present in coffee producing an undesirable effect. Bitter coffee results from the interaction of certain compounds with the circumvallate papillae on the back of the tongue. Astringency, on the other hand is caused by compounds that can precipitate salivary proteins on the tongue. Consumers will often mistakenly attribute astringency and any other potent characteristic of the coffee to the bitterness. Therefore, this article will discuss those compounds that are responsible for contributing to the bitterness of the coffee and those compounds that cause astringency in the coffee.
Why Does Coffee Taste Bitter?
Various coffee scientists have made the following observations concerning bitter coffee, which were presented in a review article by McCamey et al.:
Based upon the previous analyses, a number of steps could be introduced for making coffee less bitter:
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