It is 90-95 percent of your beer, for most people tap water will work well, but take the chlorine out by boiling, charcoal filter, you can just let it evaporate over a few hours. Minerals and pH of the water can a have an effect in the beer, these is less of a concern for extract brewers than for all-grain. Certain minerals may be added to beer to achieve flavors found in beers brewed in other parts of the world, for example the famous English pale ales of Burton-on-Trent are brewed with the very hard water found in that region. Most homebrew shops sell brewing salts that you can add to your water to give you the desired character. Or you could try adding small amounts of minerals yourself some common mineral used in brewing include Calcium Sulfate (gypsum), Calcium Chloride, Sodium Chloride (table salt) and Magnesium Sulfate (Epsom salt).
Tips: If it is good to drink it is good for beer.
The yeast metabolize (eat) the sugar, nitrogen, oxygen and amino acid and produce alcohol, carbon dioxide and esters (flavor compounds). Most of the sugar is broken down in to half alcohol and half carbon dioxide plus some trace amounts of esters. So one pound of sugar equals about half pound of alcohol and half pound of carbon dioxide. You can even weigh your wort before pitching the yeast and after fermentation, assuming you did not lose any liquid out the air lock, the amount the beer is lighter is the same amount of alcohol in the beer, this is a simple way to do alcohol by weight measurement.
There are two general types of yeast, ale and lager. Ale yeast is top fermenting yeast, it is active near the surface of the fermenting beer and it ferments at warmer temperatures, generally between 55 and 75 degrees F. Ale yeast produces fruitier flavors and aromas, depending on the strain of yeast. Lager yeast is a bottom fermenting yeast it is most active near the bottom of the beer and it ferments at colder temperatures, generally between 32 and 55 degrees F. Lager yeasts tend to be more neutral in flavor and aroma and do not produce the fruity esters found in ale yeasts. Lager yeasts are normally fermented at temperatures below 45 degrees F, following primary fermentation for a period of a few weeks to several months this is called lagering. All yeast will ferment faster at higher temperatures, but don’t do it unless you are making something you do not plan on drinking, like ethanol for your car.
Attenuation (apparent attenuation). Higher attenuation yeast eats more types of sugar for a dryer beer with more alcohol. Lower attenuation yeast is pickier about the types of sugar that it eats, this gives you a sweeter, less alcohol beer.
Flocculation. How the yeast clumps together and fall out of the beer at the end of fermentation, the bigger the flock the cleaner the beer. Triggered by the reduction of sugar and increase of alcohol, or drop in temperature.
Dry Vs. Liquid Yeast
Dry gives you a lot more bang for your buck, but you are very limited on the types of yeast. It seems the good yeast only come in liquid, if need a simple ale yeast and money is short, then you want Dry. Otherwise you want liquid. I will talk more about yeast later.
This is another topic that can be a book in itself, but since this book is mostly about extract brewing I will keep this short. There are many types of grain, in most cases you will be picking the type that you need for the style of beer you are making. Homebrew can be made just with extracts; most homebrew recipes include some form of malted grain. Specialty malts, such as crystal malt, chocolate malt (no there is no chocolate in it), and black malt, can be added to extract brews to create different styles of beers like pale ales, porters, and stouts. It is possible to brew without any extracts by mashing malted grains. All grain brewing involves mashing base malts such as pilsner or pale ale malts in place of the extract. Unmalted grains such as oats, wheat, or roasted barley are sometimes used in the brewing process as well.
Manufactures of malt extract do the 1st step of brewing for you. They steep the Malt in hot water to get the sugars out of it, then they remove the excess water for shipping. It is used as the basis for most homebrews, providing the sugars that yeast consume to produce alcohol and carbon dioxide. Malt extract comes in two basic forms Dry Malt Extract (DME) and Liquid Malt Extract (LME). Many manufactures of Malt extract make many different styles. A few years ago the selection of Malts Extracts was very limited, and the quality was not very good. This is why a lot of people who wanted good beer moved to All-Grain Brewing and this is still the best way to get the ultimate control of what is in your beer, but it is very expensive to get all the equipment needed and the time involved to make a batch of beer on brew day goes from a few hours to many hours. Today there are many varieties of Malt Extract to choose from and more commercial brewers are moving to extract brews to save time, money and floor space. You can make a world class beer from extract and not even a beer snob can tell the difference.
Tips: DME lasts longer than LME. Both last a long time but LME gets darker over time faster. If you are using any malts let the homebrew store crack them for you before you take them home.
Hops are a flowers used to season beer. Bittering hops, meaning adding hops early on in the boil process, provide bitterness to the beer to balance the sweetness of the malt. Hops added at the middle of the boil add bittering and flavor. Hops added near the end of the boil are referred to as finishing hops, add flavor and aroma to the beer. Adding hops directly to the fermenter, or dry hopping, lends additional hop aroma to the beer. Hops also serve as a natural preservative, helping to prevent spoilage in beer. Hops comes as either whole flowers, compressed plugs, pellets, or oil. If you will be using the whole flowers in your brew you will want to keep them in a bag in your wort so you don’t clog the racking cane when you transfer your wort in to the fermentor. There are many varieties of hops available to homebrewers, allowing for great diversity of flavors and aromas. Different hops are used to brew different styles of beer. For example, cascade hops give American pale ales their distinct citrusy quality, fuggles have an earthiness common in English-style ales, and saaz lend the spicy/herbal character found in European Pilsners.
Rice or corn, referred to as adjuncts in brewing terminology, can be used to produce fermentable sugars without adding body or flavor to beer. Adjuncts used in place of malt or malt extract make thinner less flavorful beers. Sugars, such as corn sugar or table sugar, can be used with the same effect.
Tips: Use the Freshest ingredients you can get. Most homebrew stores put the new sock on the back of the shelf and the oldest in the front of the shelf, this is good for the store to keep the stock in rotation, but if you want the fresh stuff get the package at the back of the shelf and check the date. When you get your ingredients home if you are not going to use them right away put the grain, malt and extracts in a cool place, put the yeast and hops in the refrigerator. The best way to keep your ingredients fresh is to use them as soon as you can. When you are brewing taste the ingredients before you add them, this is a great way to get a better feel for your beer.