What is the difference between alcohol contents measured in ABV and ABW?

A beer registering 5 percent ABV (alcohol by volume) is less alcoholic than one measured in ABW (alcohol by weight) because alcohol is about 20 percent less dense than water. Most American beers are measured in ABV while most Canadian beers are in ABW. For example, a 4 percent ABW brew would be about 5 percent ABV.

How does one become a professional brewer?

Traditionally the brewing industry has been a very nepotistic business. There was a time when it was more common than not for brewers to be the third, fourth, or fifth generation in a family of brewers. While there is still great pride and tradition in brewing families, many people are starting traditions of their own. The opportunities to start one's own brewpub or microbrewery have expanded greatly here in the U.S.

One of the most noted brewing school in the United States is the Siebel Institute of Technology and World Brewing Academy of Chicago. They offer a number of courses from online certificates to full degrees and are a valuable resource for research in brewing. Another noted school is UC Davis, which has one of the top programs for fermentation science.

These programs are very focused on brewing and are valuable but often limit students to a narrow field. Many brewers, especially at larger corporate oriented breweries, have degrees in engineering or the biological sciences and are trained for brewing within the company.

How is light beer different than regular beer? How long has light beer been around?

Light beer is a fairly new development in the history of beer. The Rheingold Brewery of New York is credited with developing the first light beer in 1967. Their product, Gablinger's Diet Beer, did not sell particularly well but was virtually handed free of charge to Meister Brau, which rolled out Meister Brau Lite. Miller acquired Meister Brau, tweaked the recipe, and in 1975 rolled out Miller Lite. In order to convince the male dominated drinking population that light beer was 'acceptable', a well-funded advertising campaign filled with masculine celebrities including sport's figures was launched. Apparently it worked well, light beer now accounts for more than half of U.S. beer consumption.

The process for making light beer concentrates on attempting to convert more natural sugars to fermentable sugars. The primary tactic is to lower the amount of malt and adjuncts. Fewer ingredients… fewer sugars. In addition, some of the steps taken in mashing, including longer steps at key temperatures, can improve the enzymatic sugar conversion. The difficult task is retaining a full body and taste profile with fewer carbs and calories.