Why Beer Bottles are Green, Brown or Clear
St. Patrick’s day was last week and it wasn’t deathly cold that night so I was going to start the evening by finally taking down my Christmas lights. Luckily, I got a much warmer offer from my friend Chris who invited me over for green beer.
Chris’s wife Jeanne was turning yellow beer into green beer using blue food coloring and Jeanne’s daughter was there too. We got talking about import beers and how many of them are in green bottles. Chris pointed out that Moosehead was maybe the only green bottled beer that he liked (and one of the few Canadian beers we get in America). That lead to a conversation about why beer bottles came in three different colors: clear, brown and green.
Chris mentioned the color of the glass protected the beer from light, which was a secret to me, so I read more about it and here’s what I found:
Origins of beer date back as far as 9000 BC in Egypt and Mesopotamia, long before refrigeration and pasteurization were invented. For this reason, beer did not keep well and all of it had to be drunk relatively soon after brewing — this is the primary reason why these times were called “the good old days.”
It’s not known exactly when glass bottles became popular for beer, but bottles can be dated back to at least 1850. Beer was put in other bottles before then. They say a monk first took beer on a picnic in a wine bottle, forgot about it and discovered it much later. To his surprise, the bottle kept the beer very fresh, more so than any other storage method.
Beer bottles were green in color until the 1930s when it was discovered that brown bottles filtered out some light that prevented the beer from going “skunky.” It’s not called “skunky” because it smells bad, it’s called that because if you expose beer to light for long enough, it will actually smell like a skunk. Chemists at the University of North Carolina and Ghent University in Belgium found that sunlight breaks down alpha acids in hops that react with sulfur to make a chemical that is nearly identical to the smelly chemical that skunks spray.
Brown bottles filter out visible and ultraviolet light that causes this reaction. Clear and green bottles don’t do much for filtering out the harmful light, clear and green bottles are often a marketing decision more than a practical one.
Clear bottles look great, showing off the color and texture of the beer while green bottles were once a status symbol for beer. After World War II, there was a shortage of brown glass, so European brewers exported their beer in green bottles. Because many of those beers were extremely high quality and others were just priced to seem that way, the green bottle became a status symbol for great beer.
Beers with little or no hops aren’t as susceptible to damage from light, so clear and green bottles are widely accepted for those beers.
Written By: Chad Upton