Brewing Basics

Before you open a neighborhood brewpub in your house, you need to learn the basics of brewing.

      I went out gigging one last time and didn't get a thing.  The run is over.  In the next few months I'll be doing much less fishing, but I'll be doing much more brewing.  The temperatures are perfect for standing around a boiling brew kettle, and my house is the perfect temperature for the fermentation of ales.  I already have a very heavy stout in mind, which I'll make when my brother is in town for Christmas.  I'll take lots of pictures so I can explain the process.  However, you will get much more out of my future tutorial if you already have a basic idea of the brewing process.  Today, I'll summarize the process so I can go into more detail when I post my tutorial.  I'll be writing about all grain brewing, which I find to be a much more rewarding process than extract brewing.  Still, if this seems too much for you to handle, you can always simplify the process by brewing with malt extract which would eliminate the complicated first two steps, mashing and sparging.


      In his free e-book, How to Brew, John Palmer states that brewing can be viewed as repeated separation and extraction.  I couldn't agree more, although, I adjust the statement and say that it is a process of conversion, separation, and extraction.  These three processes play various roles in the 5 stages of brewing: the (1) mash, (2) sparge, (3) boil (4) chill, and (5) fermentation  (brewing with extract eliminates the first 2 stages... and a lot of control over the final product).  I'll explain what is being converted, separated, and extracted at each stage
      Assuming you already have a clean work space and sanitized equipment, the first thing you do when brewing is mash your grains.  Mashing is basically mixing your grains with hot water to achieve a temperature near 153 degrees farenheit.  The type of grains used in the mash, and exact temperature of the mash depend on the goals of the brewer.  By adjusting these variables, the brewer can change the flavor, body, alcohol content, and thickness of the beer.  That is as much detail as I'll go into today, but if you interested, check out John Palmer's section on mashing.  The high temperature of the mash activates two enzymes, alpha and beta amylase, which then convert starch in the grains into sugar (predominantly maltose).  After conversion, the sugar dissolves into the water, thus separating the sugar from the grain.  The sugar-water solution is then extracted in the next stage, the sparge.
      When you sparge, you are basically just rinsing the grains.  This increases the efficiency of the brewing process by allowing more sugar to dissolve out of the grains.  During the mash, sugar dissolves from high concentrations, in the grains, to low concentrations, in the water.  Once the concentrations reach equilibrium, the dissolving stops.  During the sparge, you drain the sugar saturated water into your brewpot, and rinse with fresh (i.e. 0% concentration) water, causing more sugar to be drawn out of the grains.  The sugar water, which is now called wort, separates the sugar from the grains as it drains into the brewpot leaving the grains behind.
      After the sparge, you begin the boil.  A large amount of foam will start to form as soon as the wort reaches boiling temperatures.  It will suddenly break apart as quickly as it formed.  Brewers refer to this as the protein break.  Large, complex proteins cause the foam, and are then quickly converted to smaller forms of protein by the heat of the boil.  Hops are added at this point.  The heat of the boil helps to extract the bittering compounds, called alpha acids, out of the hops and into the wort.  It also concentrates the wort by separating some water, in the form of steam, from the wort.  Usually the boil lasts for 60-90 minutes, and then the wort is chilled.

The boiling stage.  Your house garage will be filled with the pleasant aromas of malt and hops.

      The chilling process is exactly what the name implies.  You chill your wort, to about 75 degrees, as rapidly as possible.  Chilling performs three important functions.  First, it separates the proteins from the rest of the wort.  The rapid chilling of the wort cause the proteins to coil up really fast and form large, dense precipitates, that sink easily.  If the wort is not chilled rapidly, the proteins do not curl up or aggregate as well, allowing them to drift around in your wort.  This can lead to a cloudy beer condition called a protein haze.  Chilling the beer rapidly also reduces the time between boiling the wort and pitching your yeast.  Once the wort falls below 160 degrees, it is vulnerable to infection from molds and bacteria.  You want to chill it as fast as possible to 75 degrees so you can pitch the yeast.  The sooner the yeast is in the wort, the sooner it can establish itself and out compete any bacteria or molds.  Finally, it prevents Dimethylsulfide (DMS) from building up in the beer.  It forms in hot wort, but is expelled during the boil.  However, in hot (but not boiling wort) it forms and remains in the wort.  This is not good because it can impart a sulfury or "corny" aroma to your beer.  Depending on your method of chilling (future post), cooled wort will either be siphoned into your fermentation vessel during, or immediately after chilling.  When you siphon, you leave hop debris and protein break material behind, thus extracting the precious wort from the mixture.
      With the wort in the fermentation vessel, you mix it to aerate it, (this is the only time you wan to aerate your wort or beer) and then pitch your yeast.  The yeast will function aerobically (i.e. with oxygen) and multiply.  After all the oxygen is used up, it will begin to function anaerobically.  The yeast will use sugar for energy, and in the process convert it into ethanol (the type of alcohol you drink, C2HOH) and carbon dioxide (CO2).  During this time, proteins aggregates, yeast, bits of hops, and other debris separate from the liquid (which is now almost beer) and settle on the bottom of your vessel.  When you bottle your beer, it is easy to extract the good liquid by, once again, siphoning what you want and leaving the sediment, called trub, behind.  After a few weeks, your beer is ready to bottle.

To some of you, this may look gross.  To me it looks wonderful!  That is a healthy fermentation.  By the way, it smelled way better than it looked.

      I know I mostly focused on what is happening in each stage of brewing, and not how to do each stage.  I did this intentionally.  Before you learn how to do something you have to know what you are trying to do.  You could writ a book on each stage of brewing, so I just wanted to give you some background information before I post my brewing tutorial.  When I do post it, I'll go into more detail, and tell you a few different ways to get through each stage.