What’s in a glass of beer? Most of us care a lot. Is it a stout or an India Pale Ale, is it sweet or bitter? But after two days sitting in on the very famous University of California, Davis, week-long Intensive Brewing Science course, I learned that the first thing someone who loves good beer should consider is the glass. Or rather, what’s on the glass.
Listen to Dr. Michael J. Lewis, Professor-emeritus of brewing science, one of the inspirations for the American craft beer movement:
First, Lewis said, always drink beer from a glass, not from a bottle. “If you drink beer from a bottle, you are a a pig.
“A special part of drinking beer is enjoying the aroma. That’s quite hard to do drinking out of a beer bottle _ you get a retro-nasal effect that spoils the aroma,’’ he said. “Drinking beer out of a glass is a habit I recommend everyone should cultivate.’’
However, one must consider the glass as well, Lewis says.
“We all appreciate the clarity and the carbonation that a brewer has worked hard to achieve. The beading (down the side of the glass) is a lovely sight, as lovely as the beading in a glass of Champagne.
“Finally, in a well-made beer, you have a proper head of foam. It’s an integral part of enjoying a glass of beer.’’
But, Lewis said, the foam often doesn’t last long. And that’s a not-so-subtle clue that you’ve poured your beer into a dirty glass.
Foam is quite stable. If it disappears rapidly, there’s something on the glass that is reacting with foam and killing it, Lewis said.
If you’re in a pub and that happens, you should suggest they take that glass out and smash it, he said. “Make sure your glass is clean, so at least the beer has a chance,’’ Lewis said.
“Foam on beer is a bubble of gas that has escaped; it’s an emulsion of a gassy liquid. Impurities, (grease residues, soap traces, other invisible compounds) on the glass will de-stabilize the foam.
Here’s what to do, according to Professor Lewis:
First, gather all the glasses you use for beer; look at them closely. If a glass is old and it etched with tiny scratches, toss it. All kinds of beer-killing compounds can live there.
Lewis quoted a master brewer at Anheuser Busch, who walked into a tavern with him and, of course, ordered a Bud. “The beer comes and the foam evaporates _ varooom.
He called for the manager and asked what happened to the beer, Lewis said. The manager replied that his beer was in front of him.
“Well,’’ the brewer replied, “this doesn’t look like beer. What happened to the foam? Do you realize how hard I worked to get foam in the glass?’’
Then, in true Germanic fashion (although the guy was an Austrian, Lewis said), he outline the way to care for beer glasses:
First, run an empty dishwasher with soap through its cycles. Then take all the beer glasses, put them in the dishwasher and wash them twice with soap.
After that, never in the rest of your days, put your beer glasses in the same load with other dishes. And don’t use your beer glasses for anything except beer.
Here are a few more tips, from Professor Lewis and other experts:
Let glasses air dry; if droplets remain or if spots show, it usually means the glass still isn’t clean. Wash it again.
Wash beer glasses in very hot water with a detergent, not soap.
In Belgium, bartenders immerse each beer glass quickly in cold, running water before pouring beer into the glass.
Professor Lewis adds that brewers always demand clean beer glasses. Once he visited a pub with Ken Grossman, co-founder of Sierra Nevada Brewing, Chico. “He ordered a round of Sierra Nevada Pale Ale. The beer arrived in glasses with no foam.
“I thought Ken was going to go through the roof. He said, `Look at this Michael. Where’s the foam?’’
It’s the same with brewers at the other end of the American beery spectrum. Lewis recalled