Bubbles Best For Beer Lovers

"There's no question foam is important to consumers, but whatare the attributes that make it important?" said Bamforth.

To find out what drinkers like about foam, Bamforth showedover 300 beer drinkers in the U.S., Germany, England andJapan photographs of glasses of beer poured with differentheads of foam. Then they filled out questionnaires on whatthey thought of the beer.

Most of the interviewees expected that beer with good foamwould "taste better" than a flat-looking beer, even in theU.S., where beer is often drunk straight from the bottle orcan. Some thought that the beer with good foam actuallylooked colder, or was darker in color.

Draining a glass of beer sometimes leaves a lacy pattern offoam behind. Some drinkers thought lacing meant a cleanglass, while others thought it meant the glass was dirty. Infact, lacing has nothing to do with the glass, said Bamforth.Lacing happens when the bitter-tasting compounds from hopslink proteins in beer together. Brewers can control lacing bychanging the hop extract that they use for brewing.

The survey results were published in the Journal of theInstitute of Brewing.

BEER COLOR: BETTER BY EYE?

The human eye detects differences in beer color that aremissed by equipment currently used in breweries, according tobrewing expert Charles Bamforth of the University ofCalifornia, Davis. Brewers need better methods to check beercolor, especially for ales and stouts, he said.

Color is an important selling point for beer. Brewers need tocheck the consistency of batches of beer, and with the trendto microbrews, more amber beers, stouts and ales have comeonto the U.S. market. Deeper, more complex colors are animportant part of the style of these beers.

Breweries use a machine called a spectrophotometer to checkbeer color during production, but this measures only light ofa certain wavelength, said Bamforth.

Bamforth's laboratory compared the standard methodrecommended by the American Society of Brewing Chemists witha human test. A British ale, a U.S. lager, a European lagerand a stout were diluted so that they all gave the samereading on the machine. The human judges easily spotted colordifferences that the machine did not pick up.

The study shows that consumers see beer color in ways that aone-wavelength machine does not pick up, said Bamforth.Humans cannot replace machines on the bottling lines, butbrewers need to find better ways to check on beer color andhue, especially for production of darker beers.

The research was published in the Journal of the AmericanSociety of Brewing Chemis