Friday, December 20, 2013

Chemistry of Beer: Carbon Dioxide vs Nitrogen

There's a lot of interesting science behind beer and brewing.  I'm not just saying that because I happen to like beer;  it's actually true.  Besides the interesting biology, chemistry, and physics behind the creation of beer, there is also an emerging field of research studying various health benefits of certain chemicals found in beer.

Throughout history, beer was often considered more than a nutritional or recreational beverage.  It was also considered a medicine that was, for example, used as a mouthwash and applied to wounds as a disinfectant.  The ancient Egyptians held beer in such high regard that they believed it was a gift from their god Osiris.  In fact, some breweries were able to stay in business during the US Prohibition era by producing "near beers," or very low alcohol beers, as well as a small amount of real beer that was available with a doctor's prescription.  Even as late as the 1930s, a daily glass of beer was thought by some doctors to be nutritious, particularly  for pregnant or nursing women.  

We now know that over-consumption of alcoholic beverages, including beer, can be very detrimental to health, and doctors also now discourage alcohol consumption during pregnancy.   However, many studies have supported the idea that there are some potential health benefits of some of the compounds found in beer, particularly compounds called polyphenols.  This remains an active area of research as people try to discover new chemical compounds to treat diseases like cancer and heart disease.    

I thought it would be entertaining to create another post on the science of beer.  In the previous beer post, we talked about the biology of beer and the role that microorganisms play in fermenting as well as spoiling beer.  Today, I wanted to put up a post about another interesting scientific aspect of beer: the gas dissolved inside of it.  It might sound like a kind of boring topic at first, but it's actually very important to the flavor of beer, and the topic will allow us to examine a little bit about how your body detects chemicals and how you perceive flavors in foods and beverages.