The Chemistry of Guinness: Bubbles, Bitterness, and Color

This lecture delves into the chemistry behind the iconic beer Guinness, exploring the composition of bubbles, the bitterness caused by a-acids, and the dark color attributed to melanoidins. The role of nitrogen bubbles in reducing bitterness and enhancing foam stability is discussed, along with the Maillard reaction responsible for the dark hue. The lecture also covers the stability of cyclohexanes, the energy changes in substituted cyclohexanes, and the tension in medium-sized cycloalkanes. Furthermore, it explains the structure and properties of linear alkanes, the nomenclature of branched alkanes, and the physical properties of cycloalkanes. The importance of alkanes in energy storage, membrane formation, and the petroleum industry is highlighted, along with the potential future synthesis of fuels and chemicals from renewable sources.