Tag: Used coffee grounds

According to a 2012 study, used coffee grounds contain a range of 3.59 to 8.09 milligrams of caffeine per gram, proving that a substantial amount of caffeine remains even after brewing. The idea that all the caffeine is completely extracted during brewing is a common misconception among coffee drinkers and home gardeners.

According to research published in the *Journal of Food Research*, a second brew from coffee grounds contains approximately 60–70% less caffeine than the first. This provides a definitive answer to the question: **does reusing coffee grounds reduce caffeine?** Yes, it does, but this method comes with significant compromises in taste and other compounds.