Germ theory to freezers: Breakthroughs made possible by beer

Homer Simpson of The Simpsons once said, "Beer is the cause of and the solution to all of life's problems." Indeed. Beer is one of the oldest drinks produced by humans and dates back to at least the 5th millennium BC in Iran. It was also recorded in the written history of ancient Egypt and Mesopotamia. But beer is not only a drink, it has also enabled numerous breakthroughs over the years. Here's a look at how beer led to some of the major advances in history
Discovery of gases
Thanks to beer, Joseph Priestley discovered the existence of individual gases in 1767. Priestley observed that gas floating off the fermenting mixtures fell on to the ground, indicating that it was heavier than the air around it. Following this, he discovered six other gases, including laughing gas.
A byproduct of his research was carbonated beverages, where carbon dioxide is mixed to get fizzy drinks.
Refrigeration
Refrigerators were actually created to keep beer cool. Traditionally, brewing was done during the cooler months so that the produce could be stored easily. For years, ice blocks were stored in cellars to keep beer cool.
Then German scientist Carl Von Linde introduced mechanical refrigeration in 1877. His invention rapidly displaced ice in food handling and introduced efficient compressed-ammonia refrigerator into many industrial processes. By the end of 1880s, refrigeration was common in breweries, and eventually in our homes.
Development of pH scale
pH is a numeric scale which is used to specify the acidity or alkalinity of a liquid. Now, it is majorly used for a wide range of reasons and is a mainstay of chemistry. It was initially used by Carlsberg brewers as a way to monitor fermentation of beer. 
Mercury Thermometer
English physicist James Joule invented the mercury thermometer. He was also a brewer and as such had to work in extreme precise and exact conditions. For this, air thermometers were not accurate, and he came up with the mercury thermometer to measure and define mechanical heat.

Pasteurisation and germ theory
The process of pasteurisation, used for milk, was first used by Louis Pasteur to fix beer. Local breweries wanted to know what was spoiling their beer. While at the University of Lille, Pasteur's research led to the development and proof of germ theory. This, in turn, led to vaccinations and modern medicines.
The Communist Manifesto
It is famously written that a 10-day beer drinking session between Karl Marx and Friedrich Engels resulted in the birth of one of the world's most influential political manuscripts, The Communist Manifesto. It is said Marx was a notorious drinker, and the two came up with the manifesto while travelling in France.