Today we are cleaning our draft lines. This is something that we do every two weeks to ensure our beer is tasting as fresh as possible.
Most brewers yeasts cannot fully utilize all of the available complex sugars derived from the grains that we use to produce beer. Therefore beer, unlike many other alcoholic beverages such as wine and spirits, has a residual sugar content in the finished product.
This is why, traditionally, beer is bittered (usually with hops) to "balance" that residual sweetness and increase drinkability. This is also why beer is susceptible to contamination from "beer spoiling organisms" - it has residual carbohydrates which serve as a food source for these beer spoilers. If any of these beer spoiling "bugs" get into your product (eg. through dirty draft lines) you can develop off flavors such as diacetyl, sourness, and even the dreaded "baby vomit" (butyric acid). Just to name a few.
Yes, beer is a perishable product and requires a high level of attention to detail to keep everything in the brewery as clean and sanitary as possible. Beer makes many moves throughout its life and the last movement is through the draft lines and into the serving glassware. It's the brewer's job to ensure that at every step, even this final step, that we keep everything clean and sanitary to ensure the highest quality experience for our customers.