The beans in the 'G' of Google’s doodle today give the clue.

A few details about a relatively unknown chemist who is celebrated by Google today. 225 years ago on 8 February 1794 Friedlieb Ferdinand Runge was born near Hamburg in what was then Prussia. He studied at the universities of Jena and Berlin and later went on to teach chemistry at the University of Breslau. He was a skilled analytical chemist who is credited with several major discoveries. These include the pupil dilating effects of belladonna (present in deadly nightshade), the extraction and identification of caffeine in coffee, the discovery of aniline blue, the first coal tar dye, and the isolation and naming of phenol and aniline from coal tar. He is also credited with the discovery of paper chromatography.