Chemists have identified the key compounds that can make coffee too bitter--and caffeine is not the main culprit. Steve Mirsky reports.
We may soon have better coffee through chemistry. Researchers have identified the key chemicals that can sometimes turn a sublime cup o’ joe into a bitter experience. The researchers announced their grounds-breaking findings August 21st at the national meeting of the American Chemical Society in Boston.
Studies over the last few years have found some 30 compounds that contribute to coffee bitterness. Said study leader Thomas Hofmann, “Everybody thinks that caffeine is the main bitter compound in coffee, but that's definitely not the case.” In fact, he thinks only about 15 percent of coffee’s bite is caffeine-based.
Using the analytical tool chromatography, along with taste-testing, the scientists determined that bitterness is due to two main types of compounds that form during roasting. These are chlorogenic acid lactones, the major bitterness contributors in light to medium roasts, and phenylindanes, which the lactones turn into upon further cooking, and which account for most of the bitterness in dark roasts. So perhaps in the future you’ll be ordering a grande half-caf dephenylindanerated caramel moccachino.