Beer from a keg or from a bottle?
During its long history, many myths and stereotypes have formed around our favorite drink. I want to write about one of them today.
As a brewer and taster, I am constantly being asked the same question: why does draft beer taste better than bottled beer? Let’s sort it out together, point by point. I’m not going to look at special brands, just standard, pasteurized beers.
As someone who has worked in a brewery for many years, I can assure you that both barrels and bottles are filled with the same beer, and often from the same tank. The exceptions are limited batches or beers originally made to different specifications.
Then there begins the differences. In order to keep the beer from spoiling for a long time, they do not add preservatives to it, but pasteurize it – heat it for a certain amount of time. In brewing there are pasteurization units – Pasteurization Unit, PU. One pasteurization unit (1 PU) equals one minute of holding the beer at 60⁰C.
Bottle beer and draft beer are pasteurized differently. Bottles are pasteurized in a tunnel pasteurizer. In a tunnel pasteurizer the bottles are slowly moved on a conveyor belt while hot water at a certain temperature is poured over them. The bottles are cooled with cold water when they leave the pasteurizer.
Barrel beer is warm treated in a different way, in what is known as a flash pasteurizer. Passing through the heat exchanger, the cold beer is heated very quickly and then quickly cooled and filled up into kegs, which are commonly referred to as beer kegs.
For successful pasteurization (“killing of all microorganisms in the beer”) the Temperature and the Time for which the beer has been heat treated matter. The higher the temperature, the less time is needed for pasteurization and vice versa. As a result, both bottled and cask beers receive the same amount of pasteurization units. Note that the same beer in kegs or bottles is the same in taste.
Glass bottles on store shelves can “light-struck”. Often, being on the shelf for a long time under the directed light of lamps, beer deteriorates and gets an unpleasant taste. This is due to the hops, which are sensitive to light. Draught beer is in metal kegs that protect it from light.
Bottled beer does not always, but often does not have its owner – large distribution centers cannot always control where and when bottled beer is stored. It can spoil from heat exposure in uncooled warehouses or get “light-struck” on store shelves, and it has a shelf life twice as long as a keg beer.
Beer in kegs is not stored long time in warehouses, it is received by specific people, the pub owners. They make sure the beer is fresh, the taps are sanitized, and the kegs are right stored. Pub owners don’t buy beer “for the future,” so the beer is usually fresher.
Many bars keep their kegs in special cooling rooms. This allows 2-3 times longer preservation of the freshness of an open keg of beer. All these investments more than pay off, because if the pub has stale or spoiled beer, the customer will not come back.
And finally, Psychology! Bottled beer is inexpensive. We usually buy it at home and drink it in the evening or at lunch. We don’t go to the pub every day and the prices there are 3-4 times higher than in the bottle (I mean Israel). We don’t usually go to the pub alone, but with people who are pleasant to us – friends, girlfriends… We set ourselves up in advance for the joy of conversation. Fresh beer, light shade, pleasant waitresses, and soft music also contribute to it. All this works together and brings a feeling of simple human happiness, and even small faults from the taste of beer cannot take away that feeling of a holiday, for which we came to the pub.