A New Look at Brewing

Revamped, Expanded, and Updated by Aaron J. Schohn (April 30, 1999) 
Compiled from previous sites authored by Christopher B. McIlroy, Aaron C. Bandremer, & Ken Takeda 

32.443 Introduction to Biochemical Engineering
Rensselaer Polytechnic Institute
Troy, NY 12180

Comments or questions:



Beer- is there anything it can't do?

Since early times beer has played an important role in our society. It brings people together in local pubs and breweries generating camaraderie within communities. As technology has progressed, brewing techniques have been developed and refined. As a result, we are currently consuming the finest beers ever produced. This is due to our increased knowledge in the fields of biotechnology, microbiology, and chemistry. 

The process of beer brewing consists of several steps, which result in a beverage that has a unique taste. The most important operation of the brewing process is fermentation. By definition, fermentation is a process by which yeast and natural enzymes convert carbohydrates in fruits and grains into alcohol and carbon dioxide. This knowledge has been known for ages, but we are just beginning to apply state of the art technology to control and improve the process. The following presentation is intended to educate the "casual observer" of the brewing process.

First, I think it is appropriate to examine how beer and its fermented predicessors have been involved in society throughout history.

  • The Evolution of brewing 



    It was decread long ago that only 'pure' beer should be sold to the public. The origin of these purity laws dates back to Germany. A translation of one such law is listed below. 

  • German Purity Law of 1516 



    (Note yeast is not included in the list of acceptable ingredients. At the time yeast was refered to as 'Godisgood' - the chemical reaction was not understood and most thought it was magical. Yeast was introduced by the re-use of the brewing vessel and not directly by the brewer.)

    Overview of process

    The four main ingredients for making beer are:

  • Water
  • Malted Barley 
  • Hops 
  • Yeast 
  • A Little Yeast Biology



    Fermentation Biochemistry: Reaction of glucose to ethanol 

    Brewing Schematic: Displays the six major process units 

    Introduction to Home Brewing: How to get yourself started! 

    Glossary of Beer Brewing Terms

  • A Brief look at the industry in the US
  • Link Page (Sites that I frequent and that you might enjoy!)
  • Bibliography (give credit where credit's due)

  • Previous student term projects:
    Project 1 Project 2  Project3
    Project 4 (tips and recipes)