Welcome class! We're going to begin our beery adventure in earnest this week. Unit 1 will be set in most people's first stop on the path to beer greatness: The taproom. Yet, before you pull up a stool at the bar there are four very important things you should know before taking a sip: what's in my glass?

Lesson 2: The Four Main Ingredients

As mentioned in Lesson 1, beer has taken a long meandering route to get to what it looks and tastes like today. While in eons past pretty much anything was chucked in a vessel with the hopes it would come out somewhat palatable on the other side, today is a different story. Thanks to the discovery of yeast by Louis Pasteur, advanced kilning methods by Daniel Wheeler, different chemical makeups of water and the happy discovery by the Germans that hops made it all taste better we have modern day beer. And it doesn't look or taste like slop.

That's right, these four basic ingredients go into every glass of beer that you'll have at your favourite brewery's taproom: yeast, malt, water and hops.

There have been wars fought (well, not real wars) over which ingredient is the most important in beer but, truth be told, you really can't have one without the other. Therefore, they're all equally important to your glass. Let's get to know them each a little better.


Without yeast, beer wouldn't have alcohol. Indeed, it's the yeast the takes the sugars from the malts (which are extracted during a process called "mashing", which we'll discuss in future lessons) and converts them into alcohol and CO2. When healthy, they're a frisky bunch multiplying by the billions and getting down to business eating away at the sugars and letting off ethanol and CO2 as their byproduct. Yep, beer is yeast farts.

There are two different categories of yeast: ale and lager strains or Saccharomyces Cerevisiae and Saccharomyces Pastorianus, respectively. In brewing circles ale yeasts are known at "top-fermenting" while lager yeasts are called "bottom-fermenting" because that's what they literally do during their respective fermentation processes. These two divergent strains do their job best under differing circumstances. Ale yeasts ferment at typically higher temperatures--about 10-25?C while lager yeasts prefer about 7-15?C to do what they need to do.

Besides being responsible for putting the "p" in party, yeast does impart flavour into beer. Ale yeast strains, since they ferment at a higher temperature for a shorter period of time, produce flavours such as fruity esters (banana, strawberries, apples), phenols (cloves, spice, plastic) and several other compounds like acetaldehyde (green apples) or diacetyl (butterscotch). Lager yeasts, on the other hand, do their job low and slow so they are typically a little less responsible for providing flavour as all the compounds necessary have been eaten away by the yeast. Nevertheless, certain flavours like creamed corn (Dimethyl Sulfide) can exist. It's important to note that many of these compounds can exist with both strains it's just that lager yeasts typically eat up most of them before they're done.

Yeast is responsible for alcohol, carbonation and some flavour in beer. 

There are two species of yeast strains responsible for making beer: Saccharomyces Cerevisiae and Saccharomyces Pastorianus (Ale and Lager, respectively).

Ale yeast is called "top-fermenting" while lager yeast is called "bottom fermenting".

Ale yeast ferments at higher temperatures than lager yeast.


Malt is the word for grains that have gone through a process called "malting". The vast majority of grains that are used to make beer are either barley or wheat, although speciality grains such as spelt, oats and rye can be used as well as corn or rice (called adjuncts)

The malting process begins by soaking the grains in water in order to germinate. They are then dried using hot air to stop the germination. Doing so develops an enzyme that can take the grain's starches and convert them to sugar, giving yeast the food they need. Once the grain has gone through these first steps they are then roasted in a kiln for varying lengths and temperatures in order to achieve the desired colour. It's all very scientific--and a little bit magic--but without the malting process, we'd really be stuck with just a bunch of grain.

When making a beer brewers rely on what's a called a base malt. This is typically malted barley and can come in either whole grain or extracts (dried or liquid, DME or LME respectively). Other grains can be added to the mash (discussed later) in order to achieve some desired qualities. Wheat is good for body and head retention while oats can give a nice silky mouthfeel. Deeply kilned malts can add deep, dark colours and also produce some interesting roasted flavours. There are a million things that different malts can do. We'll refrain from going down the list here about what each grain can do but if you've got a grain, any grain, chuck it in and see what it can do.

Hopefully it's become apparent that malts play a very important role in beer. Not only do they provide the sugars necessary for the yeast dinner but they are also responsible for a beer's colour, body, mouthfeel and a good bit of flavour. What an exhausting job!

Malts are responsible for colour, body, mouthfeel, flavour and giving yeast the sugars they need

Grains used in beer are typically barley, wheat, oats and rye.

Raw grains go through a process called "malting" in order to acquire the enzyme necessary to convert starches to sugars.

Kilning, or toasting, the malts achieves desired colour.


Ahh water, without it beer wouldn't be very--well--wet. Yet water plays a much more important role than just making beer liquid-y. Not only is it vital in the brewing process, water also has a certain chemical makeup than can affect the outcome of a beer just as much as the other ingredients can.

One of the first things necessary when brewing is a boiling pot of water. While we'll go into the brewing process a bit more in depth in a future lesson, it's important to know that steeping the aforementioned malts in water for about an hour converts the starches into sugar and creates "wort". This sugary water is then boiled, has hops (!) added to it, chilled and then becomes a watery dinner party when the yeast is "pitched". Things are getting delicious.

The chemical makeup of a water source varies greatly from town to town, country to country. Our beer-making foremothers' beer recipes were adjusted and fine-tuned according to what their local area presented them. Without realising it, certain chemical compounds existed in their local water supply which had an effect on their end product. The water in the Plsen area of the Czech Republic is famously soft, with very little in it, and is best suited for the delicate Bohemian Pilsners. Equally as famous is the calcium sulfate from the waters around Burton-on-Trent. Otherwise known as gypsum, it gives the area's water a hard, dry mineral content which is highly suitable for making pale ales (the sulfates give off a noticeable whiff of sulfur, affectionately known as "Burton Snatch").

It's important to remember that many city water supplies can be treated with high levels of chlorine and the like. While that is perfectly safe it can have an effect on the final flavour of a beer. Now days there are easy-to-use water treatments available that can help adjust the water to better suit your recipe so you don't have to go to Plsen with a bucket if you're trying to brew a Bohemian lager. Thank you technology!

Water is the basis of the brewing process and responsible for creating "wort".

It has a varying chemical makeup which can have an effect on the flavour and character of a beer.

Local water can be treated with water treatments to adjust the chemical makeup according to a brewer's needs.


Finally! Beer lovers, Ratebeer contributors and hop farmers can rejoice! It's time to talk about hops. The final, and most exciting, ingredient in modern beer. These little flowers, scientifically known as Humulus lupulus, have a big role in beer.

Grown all over the world, some of the most famed hop-growing areas are the Pacific Northwest in the US, New Zealand, Kent, Germany and the Czech Republic. Hops grow on a robust vine which is trained to climb wires (young hop farms tend to look like telephone pole farms) and are harvested in late summer. They can be used right off the vine--called "wet hopping"--dried, or pelletised. Dry-hopping is when hops are added to beer after it's already undergone its primary fermentation.

With hundreds of varietals in existence--and more experimental ones coming out all the time--it's impossible to discuss each of them in depth. What's important to note, however, is that each hop--in varying degrees--is responsible for flavour and a bitterness which balances the sweet "wort". Depending on the varietal, the flavour and bitterness intensity--known as International Bittering Units (IBUs)-- can change. Much like grapes, hops can change based on the terroir. Classic American hops like Cascade, Centennial or Citra are known for their grapefruit, citrus and pine tree character as well as big bittering qualities notable in most American IPAs. New Zealand hops like Nelson Sauvin or Motueka bring with them flavours of the South Pacific: tropical fruits and zesty white wines. The noble hops of Hallertau, Tettnanger, Saaz and Spalt from Germany and the Czech Republic aren't powerfully bitter but are instead recognized for their strong aromas which are distinguishing characteristics of European lagers. Finally, the great English noble hops like Fuggles and Goldings are famed for grassy, minty, florals or zesty citrus character and are widely used in most classic British styles.

While that's all fun and games, hops also have an important vocation: they act as a preservative. Hops have a stabilising effect on the foam qualities of beer as well as extending the shelf life. There is also a small antibacterial property to hops that helps keep a beer from going bad. We wouldn't use it on your washing up, however.

Hops are important for adding flavour and bitterness as well as its antibacterial and preservative qualities.

They are grown on vines all over the world but primarily in the US, UK, China, Germany and Czech Republic

Hops can be used as whole flowers, dried leaves or pelletised.

Bitterness is measured in IBUs (International Bittering Units).


There you have it: at the very least, it's these four things in your glass. You are now ready to continue this beery quest for knowledge and walk through the doors. Next week we'll take a visit to some of our favourite taprooms and those which really excite us so you know where to enjoy a glass of yeast, malt, water and hops. Cheers!