Now that you know what beer is made from, it’s time to learn how it’s made.
If you haven’t yet read it, I’d highly recommend starting with this series on “What beer is made from” from first.
As a quick reminder, beer is made from 4 ingredients: malt, water, yeast and hops
Malt provides sugar, that yeast ferments into alcohol and carbon dioxide, in a liquid environment provided by water, and hops bring the bitterness to balance out malt’s sweetness
Here, we’ll talk through each step of the brewing process and its flavor impact.
Before we get started with brewing though, we’re going to quickly recap one step that happens before the brewhouse… malting.
Ready? Let’s get started.
Malt is shorthand for malted barley; in other words, barley grains that have gone through the malting process.
Barley is a grain that contains starches, which serve as energy reserves for growing a new plant. But starches are long chains of sugars and yeast can only ferment simple sugars, or short chains.
So barley is put through a process called malting, so that its starches can later be converted to sugars during the first step of the brewing process – mashing.
As you’ll recall from this article on malt, malted barley doesn’t just contain starch. It also contains all important enzymes, which convert that starch to sugar. (Enzymes are molecules that help speed up chemical reactions.)
Before mashing begins, malt is milled or crushed, as this exposes more surface area for the enzymes to act on. The crushed grains are then mixed with warm brewing water, or liquor, as it’s more technically known.
During the mash, sugar is “extracted” from the malt and dissolves into the water producing a sweet liquid called wort.
You may remember from this article on water that the minerals in our brewing water can alter the pH of the mash, which in turn effects the activity of malt’s enzymes.
But, enzyme activity is also impacted by the temperature of the mash, too.
At a lower mash temperature, the production of simple sugars is favored; as these sugars can be fully fermented by yeast, this produces a thinner bodied, drier beer.
At higher mash temperatures though, more dextrins, or unfermentable sugars, are produced. As these sugars can’t be fermented by yeast, they stick around the finished beer making it taste sweeter and feel fuller.
Making adjustments like these enables brewers to really fine tune their wort to best suit the beer style they’re brewing.
Brewers can also add in specialty malts and alternative grains during the mash to bring different colours, flavours, and textures to beer.
From here, all we want to move forward with is our sweet liquid or wort. (We don’t need the grains any longer as they’ve given up their sugars.) So we separate the liquid from the solid in a process called lautering and the wort moves on to the next step – the boil.
During the boil is when we add our hops, which give beer bitterness, aroma and flavour.
As we discussed in this article on hops, hops’ bittering component – alpha acids – need to be boiled in order to change shape, dissolve into the liquid, and impart their bitterness.
But hops’ aroma and flavour compounds – the essential oils – are very volatile, so they dissipate quickly during the boil.
To focus on this aspect of hops’ character – the ‘spice’ – more hops will be added late in the boil, just after the boil, or after fermentation when the liquid has cooled. (This final approach is called dry-hopping and we’ll mention it again shortly.)
The boil also plays a few other important roles:
- it helps to clarify the beer, making any proteins settle out.
- the high temperatures can cause some caramelization of the sugars in the wort, making malt’s flavours even richer.
- and importantly, it’s a sanitation step; so from here, cleanliness is key.
Next, the boiled, bittersweet wort must be filtered to remove any hop debris and cooled to bring it down to a suitable fermentation temperature… which depends on what family of yeast is being used for fermentation
Broadly speaking, there are 3 families of beer, determined by the type of yeast used: lager, ale, and mixed fermentation.
As you’ll recall from this article on yeast:
- Lager yeast ferments around 10 °C (50 °F) for 7 – 14 days at a minimum, often followed by a long cold conditioning phase.
- Ale yeast prefers warmer temperatures, closer to 20 °C (68 °F), which speeds up the process, taking approximately 3 – 5 days.
- Finally, mixed fermentation – which uses a combination of brewer’s yeast, plus wild yeast and bacteria – often ferments at ambient temperatures and can take from months to years.
Once the appropriate fermentation temperature is reached, yeast is “pitched” or added into the wort.
As yeast replicates, the sugar in the solution is consumed and alcohol and carbon dioxide are produced.
Aromatic esters and phenols may also be produced, dependent upon the yeast strain being used. These fruity and spicy flavours are much more common with ale yeast over lager yeast because of the temperatures they ferment at.
Most beers in the ale and lager family are fermented in enclosed stainless-steel vessels.
Some beers in the mixed fermentation family follow a similar approach initially, but the beer is often moved into large wood barrels for aging, which house the wild yeast and bacteria that sour the beer. But mixed fermentation can also take other approaches, like spontaneous fermentation or kettle souring.
In spontaneous fermentation, no yeast is pitched! In this very traditional method, the boiled wort is cooled in a large, shallow open vessel and wild yeast and bacteria present in the brewery settle in to start fermenting. (This beer is also long aged in wooden barrels, so more wild yeast and bacteria can be introduced that way, too).
In kettle souring, lactic acid bacteria is added to the sweet wort before it’s boiled. The bacteria consumes some of the available malt sugars, producing lactic acid and giving the beer a sour taste. Once the desired pH is reached, the wort is boiled, killing off the bacteria. Then, after the wort has cooled, fermentation carries as normal – ale yeast is pitched to give the beer it’s alcohol and carbon dioxide.
(While kettle souring is a much quicker way to make a beer with a sour taste, it’s important to note that these beers won’t have the same funky flavours and complexity found in long aged mixed fermentation beers.)
Again, some brewers welcome wild microbes into their brews, but others view them as contaminants and stick to ale or lager yeast only.
Regardless of the type of yeast used, fermentation is a pretty wild process and there are often lots of other flavorful compounds that are produced that yeast will go back in and clean up. So let’s talk about the final step of the brewing process – the conditioning phase.
As beer matures, any rough flavours age out. Lagers condition for longer than ales, further enhancing their “clean” fermentation character.
Hops may also be added here for dry-hopping. Along with fruit, herbs, spices or other ingredients and flavourings.
After conditioning, the yeast will be recovered so it can be reused, or re-pitched, as this helps with consistency from batch to batch.
Beer will typically brighten, or clarify, during the conditioning phase, as yeast and other particulates settle out. Depending on the brewery size or style of beer, further steps may be taken to improve beer’s brightness and shelf-stability.
Filtration is often used to remove particulates and increase clarity, while pasteurization – briefly heating the beer to kill all remaining microorganisms – gives the beer a longer shelf life. Alternatively, beers can remain unfiltered and unpasteurized.
From here, the beer is packaged into kegs, cans, bottles, or casks.
Beer can be force carbonated prior to packaging, or it can develop its carbonation once packaged, like in cask- or bottle-conditioned beers.
In this case, a small amount of sugar and fresh yeast is added into the beer when it’s packaged; the yeast then consumes the sugars, carbonating the beer right inside the vessel.
Finally, the beer is shipped out to consumers to enjoy!
And, there you have it, a whistle stop tour of how beer is made!