Chris Boulton is currently lecturer and Professor in Brewing Science at the University of Nottingham, and formerly spent some 25 years with Bass Brewers and latterly Molson Coors UK.
As a biochemist, I found an excellent section on enzymes and brewing. There are also definitions of the terms extract, kettle hops, green beer and micronised grains. ( Chemistry & Industry , 20 November 2013)