Google celebrated the life of Søren Peder Lauritz (S.P.L.) Sørensen on Tuesday with an interactive homepage doodle that pays tribute to the Danish chemist. While Sørensen was working as the chemical director of Carlsberg Laboratories, the operations affiliated with the Carlsberg brewery, he developed the logarithmic pH scale that measures the acidity or basicity of a solution. A massive discovery for which he’s best come to be known, the scale helps scientists understand the chemical composition of liquids, and its discovery has been invaluable.

Sørensen was born in 1868 in Havrebjerg, a small town that is today home to around 500 people. At the age of 18, he went to study at the University of Copenhagen, studying chemistry after being influenced by Sophus Mads Jørgensen. Sørensen didn’t spend his whole life working as a chemist, as he also briefly worked in consultancy for the royal naval dockyard. In 1901 he took up his position at the Carlsberg Laboratories, an institute established in 1876 by brewery founder J.C. Jacobsen to further the development of beer. It was here that Sørensen developed the scale.

S. P. L. Sørensen
S. P. L. Sørensen

In 1909, when he created the metric, Sørensen was studying the effects of ion concentration in proteins. Sørensen developed the pH scale, which measures the concentration of hydrogen ions, as scientists were moving from color-changing tests for measuring acidity to electrical-based systems. The scale ranges from 0 to most acidic, 7 to neutral, and 14 to most basic. The discovery pushed him into studying the application of thermodynamics to the field alongside his wife Margrethe Høyrup Sørensen.

Sørensen left the lab in 1938, the year before his death, but his legacy endures. Carlsberg notes that his “pioneering research has had a profound effect on beer and science.” It’s listed on the company’s website as one of its biggest contributions to the world of brewing, alongside other breakthroughs like the cultivation of pure yeast.

It’s not the first time Google has paid tribute to a famous science discovery on his homepage. The search engine honored NASA’s discovery of a multiplanet star system in February, and it’s also commemorated geochemist Katsuko Saruhashi and biochemist Har Gobind Khorana.

Through a quest to perfect the pint, Carlsberg’s top scientist helped change chemistry forever.