The Chemical Institute of Canada Toronto Local Section hosted a Brewery Tour and Sponsor Appreciation Night last December at the Mill Street Brew Hall in the city’s historic Distillery District. It was a great opportunity for local section members to meet sponsors while learning about the art and science of brewing from head distiller, Kaitlin Vandenbosch (pictured above). Participants learned that the bitterness in beer is caused by the presence of alpha-acids (such as humulone), however, they are not very soluble in the wort (unfinished beer). During the boiling step they react and isomerize (humulone to isohumulone), making the acids more soluble and thus increasing the bitterness.