Most beer drinkers probably don鈥檛 care a jot about the environmental impact of their favourite tipple. But they will soon be able to reduce their carbon footprint nonetheless, thanks to a technique that slashes both the energy required to brew beer and the amount of waste produced in the process.
The idea, 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. 鈥淭he steam rips the liquid apart completely to form tiny, atomised droplets,鈥� says Jens Thorup, PD鈥檚 technical director. 鈥淭he droplets create a massive surface area that speeds up brewing reactions.鈥�
This stage of beer-making 鈥� when hops are added to liquid containing malted cereal grains 鈥� is called the 鈥渨ort boil鈥�, and it鈥檚 when 60 per cent of the energy required to make beer is expended. In a two-year trial at the Coors brewery in Burton upon Trent, Staffordshire, PDX cut wort-boil energy consumption by 40 per cent. And with reactions taking place in steam rather than fluid, less solid waste was 鈥渂urnt鈥� onto surfaces, reducing the need to later purge vessels with caustic chemicals.
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Brewers Shepherd Neame of the UK and Carlsberg of Denmark are now set to adopt PDX, too. 鈥淭here are certainly savings to be had, and in most cases they are substantial,鈥� says Richard Sharpe, technical director of BRI, a brewing research lab in Nutfield, Surrey. 鈥淲hen brewing鈥檚 finance chiefs get a sniff of the savings this will take off.鈥�
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