Bart, a woman is like
beer. They look good, they smell good, and you'd step over your own mother just
to get one! ~Homer Simpson
Beer is one of the
oldest beverages humans have produced,dating back to at least the 5th
millennium BC and recorded in the written history of Ancient Egypt and
Mesopotamia. On Friday June 9th the OPS will host its
annual Mid-Year Program at the Medical Biomolecular Research Building at the
University of North Carolina, and there will be a Home-Brew reception
immediately after the courses. You might be surprised to find how many OPS
members brew beer. There are at least 7 members that I know of who brew on a
regular basis. The reception will showcase various styles of beer and how they
pair with food and ophthalmology like Cherry Red Spot Wheat or Pink Eye Pale
Ale and Iris Bombe India Pale Ale.
There are many facets
to brewing and you can make it as simple or complicated as you want. In this article we are going to explain the
basic process of brewing and terminology. Brewers combine four simple
ingredients to make beer, barley, water, hops and yeast. A complex series
of biochemical reactions must take place to convert barley to fermentable
sugars, and to allow yeast to live and multiply, converting those sugars to alcohol.
SO WHAT IS BEER?
the traditional Reinheitsgebot (German purity
laws) from 1487, forbade the use of ingredients other than barley, hops,
water and yeast. Those laws have since been relaxed, and many beers are also
made using other grains such as corn, rice and wheat. Barley - is the seed of a
grain that looks a lot like wheat. Before barley can be used to make beer, it
must be malted, which involves a natural conversion process.
First, the barley must be allowed to germinate, or
start to sprout. This is done by soaking the barley in water for several days,
and then draining the barley and holding it at about 60 degrees Fahrenheit
(15.5 C) for five days. During the germination process, enzymes released by the plant convert these nutrients (which are starches) into sugars
that can feed the plant while it grows. The key to the malting process is to
stop the germination of the barley at a point when the sugar-producing enzymes are present but most of the starch is still
unconverted. Eventually, these enzymes will produce the sugars that will feed
the yeast to make the alcohol in the beer. The intensity of the malt
flavor and color depends on how high the temperature is raised during the
Hops- contain acids, which give beer its bitterness, as well
as oils that give beer some of its flavor and aroma. Adding hops to beer also
inhibits the formation of certain bacteria that can spoil the beer. There are
many different kinds of hops, each of which gives a different taste, aroma and
amount of bitterness to the beer it is used in. In the United States, hops are grown mainly in Washington, Oregon
and in a many homebrewer’s backyards.
Yeast- Yeast is the single-celled micro-organism that is
responsible for creating the alcohol and carbon dioxide found in beer. There
are many different kinds of yeasts used to make beer; and just as the yeast in
a sourdough starter gives sourdough bread its distinctive flavor,
different types of beer yeast help to give beer its various tastes. There are
two main categories of beer yeast: ale yeast and lager yeast. Ale yeast is top fermenting, meaning
it rises near the surface of the beer during fermentation, and typically
prefers to ferment at temperatures around 70 F (21 C). Lager yeasts are bottom fermenting. They
ferment more slowly and prefer colder temperatures, around 50 F (10 C).
HOW TO BREW BEER
The Mash Process
The mash process converts the starches into fermentable sugars. This is done by
crushing the malted barley to expose the kernels so the sugars can be extracted
from the grain. The crushed malted barley is placed in lauter tun (insulated
container) and the malted barley is allowed to mash or steep for an hour at 150
F (65 C ) – 170 F (76 C) degrees .
The next step in brewing is called the boil. The end result of the boil is the finished wort. To start, the liquid mash is transferred to a brew kettle and is
brought to a vigorous rolling boil and is held there for 60 to 90 minutes
depending on the style of beer.
Hops are added to the boil at various stages. At the start
of the boil hops are added to give the beer its bitterness. This allows maximum
time for the acids in the hops to be extracted. A second round of hops is added
in the middle of the boil to produce the hop flavor and aroma. The last round
of hops is generally added about 15 minutes before the end of the boil
contribute the flavor the beer.
Chilling the Wort
The wort must be chilled quickly so the yeast can be added and fermentation can
begin. This reduces the chance of contamination by stray yeasts floating around
in the air.
Fermentation is the process by which yeast converts the sugars in the wort to alcohol and carbon dioxide gas giving the beer
both its alcohol content and its carbonation. The wort
is "racked” or transferred to container where the yeast is added and the solids
(grains and hops) are allowed to settle out. This process takes approximately
2-3 weeks and may involve a transfer to another container for more clarity.
Bottling or Kegging
The last step is bottling or kegging the beer. The most important thing about
the bottling and kegging process is to keep the beer from being contaminated by
stray yeasts, and to keep oxygen away from the beer. These are the main things that can reduce the shelf-life of
To see the step by step process you can view it here (Come back to check out the video soon!)
Brewing beer is very fun, simple and rewarding. We look
forward to seeing everyone at the OPS Mid-Year Program and hope you partake in