The human eye detects differences in beer color that are missed by equipment currently used in breweries, according to brewing expert Charles Bamforth of the University of California, Davis. Brewers need better methods to check beer color, especially for ales and stouts, he said.
Color is an important selling point for beer.
Brewers need to check the consistency of batches of beer, and with the trend to microbrews, more amber beers, stouts and ales have come onto the U.S. market. Deeper, more complex colors are an important part of the style of these beers. Breweries use a machine called a spectrophotometer to check beer color during production, but this measures only light of a certain wavelength, said Bamforth. Bamforth's laboratory compared the standard method recommended by the American Society of Brewing Chemists with a human test. A British ale, a U.S. lager, a European lager and a stout were diluted so that they all gave the same reading on the machine.