Samples underwent high-performance liquid chromatography, and the “clear winner,” the company says, was Black Insomnia at “an incredible” 17.5 grams of caffeine per kilogram of coffee.

The group operates a chain of coffee outlets here and in the UK and the €39m revenues for 2023 top pre-covid-19 revenues of €36.77m for 2019. It recorded revenues of €39.16m in Ireland and ...