Beer goes a little greener

People visiting their local pub to drink a pint could see their carbon footprint reduced, thanks to a technique that cuts both the energy required to brew beer and the amount of emissions produced in the process.

The concept, called PDX, comes from Pursuit Dynamics of Huntingdon, UK. It adds a seemingly drastic step to conventional brewing: it blasts steam at supersonic speeds into the vat of brewing liquor to heat, agitate and atomise it. “The steam rips the liquid apart completely to form tiny, atomised droplets”, says Jens Thorup, PD’s technical director. “The droplets create a massive surface area that speeds up brewing reactions”.

This stage of beer-making-when hops are added to liquid containing malted cereal grains-is called the “wort boil”, and it’s when 60-per-cent of the energy required to make beer is expanded. In a two-year trial at the Coors brewery in Burton upon Trent, Derbyshire, PDX cut wort-boil energy levels by 40-per-cent. And with reactions taking place in steam rather than fluid, less solid waste was “burnt” onto surfaces, cutting the need to later purge vessels with caustic chemicals.

Brewers Shepherd Neame of UK and Carlsberg of Denmark are set to take up PDX, too. “There are certainly savings to be had, and in most cases they are substantial,” says Richard Sharpe, technical director of BRI, a brewing research lab in Nutfield Surrey. “When brewing’s finance chiefs get a sniff of the savings this will take off”.