Beer is an alcoholic beverage made from 4 basic ingredients: water, malted grain (usually barley), hops and yeast.
Water is an important ingredient since it constitutes roughly 90% of your beer. The technical brewing term for water is ‘liquor’ (never quite understood that one!) The varying minerals in water can affect the sugar extraction from the malts and can lead to distinct flavours and qualities to a beer. Historically different areas became famous for distinct styles of beer because that location had the best water for the type of beer. Eg. Pilsen – Pilsner beer, London – Bitters and Stouts, Rocky Mountains – Lager.
As beginning home-brewers you don’t need to worry too much about your water. To be safe, a good practice is to run your water through a charcoal filter or buy a large cheap container of bottled drinking water. In general, softer water makes for cleaner lagers and pale ales and hard water is best for more robust ales, stouts and porters. Be careful not to use water from a softener though because it has too much salt in the processed water.
There is a whole science to the components of water and how they affect your beer brewing. As you progress in your home-brewing you might want to check with your local water authority on your local break-down of ions and minerals and research what you can do to create the ultimate ‘liquor’ base for each type of beer you brew.
You may have heard this word a thousand times, but what is malt really?
Malt comes from germinated cereal grains. Beers can use a variety of grains, but barley is most often used. Malt is to beer, what grapes are to wine; that is, the basic ingredient from which we as brewers derive the sugars which we can ferment to make beer.
Barley is essentially a seed and contains within its thick husk all the potential energy to start and sustain plant growth. In order for us to access this energy (sugars), we need to activate the enzymes within the grain and get them to start converting the starch into sugar. We do this through a process known as “malting”. The grains are left in a warm and wet environment for a few days (simulating Spring-time conditions) which triggers chemical reactions to occur within the grain signalling for it to start growing. When this happens certain enzymes within the grain are activated and begin to convert the starch into sugar.
This process is then abruptly stopped by heating and drying out the grain. The grain goes into a dormant state where it can remain for many months until we want to use it. As brewers we then re-start this process for our own use by steeping the grains in warm/hot water at just the right temperature to enable the enzymes to carry on with their work converting all the carbohydrates into sugars. As the sugar is created it goes into the water and becomes what we call our ‘wort’.
Hops are a climbing flowering plant – found growing wild across much of the UK countryside and now cultivated around the world. It is notable for its distinctive cone-shaped green flowers which contain a highly potent resin. These flowers, or more specifically the oils and resins found within them, are used to add bitterness, flavours and aromas to beer. In the past many other herbs and flowers were used to flavour beer, but with its antimicrobial properties, hops has become the favoured substance.
Hops can do different things for your beer depending on when they are used. When added early in the boiling process they create the under-current of bitterness through the beer. The closer they are added toward the end of the heating phase, the more they contribute to the aroma of the beer. In fact, to create the maximum amount of aroma, brewers do what is called ‘dry-hopping’ which means adding the hops into the cooled and fermenting beer so that no heating breaks-down the aroma.
Like the grapes used in a wine, different regions of the world are now known for their own varieties of hops – each having its own characteristics and flavour profiles.
As one of only 4 ingredients, yeast is often overlooked. However, it is a very important ingredient. It is often said that “we make the wort, but the yeast makes the beer”. Historically people didn’t even know that yeast existed and for hundreds of years believed that the only ingredients in beer were the grains, water and hops. Families had their own brewing sticks which they used to stir their wort. This stick, unknown to them, held all the yeast and re-introduced it to each batch of their beer. Their stirring stick with its distinctly developed strain of yeast then became a differentiator between different brewers. Even today, breweries who harvest their own yeast and re-use yeast from batch to batch develop their own unique flavour profile that is not able to be copied.
Yeast is a single-cell living organism which can be found in abundance all around us. There are over 500 different species of yeast – of which “Brewer’s Yeast” is only 1. Within this single species there are literally thousands of different strains. It is these different strains which brewers use in different beer styles to produce distinct results. Characteristics that define brewer’s yeast are: ability to convert sugar to alcohol (attenuation), alcohol tolerance, ability to stick together (flocculation) and finally the flavour characteristics added to fermentation. Different strains will display these characteristics in a variety of levels – resulting in completely different beers.
Yeast contributes over 600 different flavours and aromas to finished beer. Fermenting the same wort with four different yeast varieties will produce four distinctly different final beers. Today high-end yeast retailers have developed very specific strains of yeast which are designed for use in specific beer styles.
Other yeast species cannot convert sugar to alcohol or exist in an alcoholic environment, nor do they “stick together” – which is why you cannot use your bread-making yeast to make beer!
Once the yeast is added to the wort, it will undergo a transformation process whereby it assimilates to its new environment before it begins to multiply. Add too much yeast and it will not need to multiply much to convert all the sugar and so will become “lazy”. Add too little and the yeast cells will have to work overtime to get the job done – burning themselves out. Neither situation will produce brilliant results. Therefore, not only is it important to consider the variety and quality of the yeast used, it is vital to add the correct amount needed for the job.
The final point to consider with yeast is the actual fermentation conditions. In general, much attention is given to the brewing process to ensure production of good quality wort, with little regard for the fermentation process beyond pitching the yeast. In reality, many factors will affect the ability of the yeast to do a good job, but perhaps the most important is temperature. Too high and the yeast multiplies too rapidly, producing more by- products. Too many of these by-products will ultimately affect the end beer and can make it undrinkable. Too low and the yeast will be unable to multiply and ferment. The optimum temperature range for most strains to ferment is 18-22oc (note that lager yeast ferments at lower temperatures; around 12oc.)