Carlton and United Commissions a Liquid-CO₂ Hop-Extraction Plant

In 1980, Carlton and United Breweries commissioned a commercial plant in Australia for extracting hops with liquid carbon dioxide. The company’s scientists reported work progressing from laboratory and pilot equipment to commercial-scale extraction. Their research formed part of an international move toward CO₂ processing, including earlier work by Britain’s Brewing Research Foundation and Distillers Company. Hop extracts concentrated bitter resins and aromatic oils while leaving much of the plant material behind, supporting controlled additions in industrial brewing. Extraction itself was much older: the significant change was the solvent and the practical scale. Liquid CO₂ offered an alternative to earlier organic solvents amid concern about residues in food. It was distinct from mechanical pelletization and from extraction with supercritical CO₂, another route developing around the same period.