The Beer Brewing Process

Firstly, it seems that ingredients can vary from one beer to another. The most common ingredients are:

• Water
• A source of starch – typically malted barley
• Hops
• Yeast
• Sometimes what is called a “clarifying agent”

Looking at that list of ingredients, some are more familiar to me than others. What should I look at next – should I take a closer look at the ingredients, or how they fit into the process?

I thought I’d look more closely at the process – this might help me to see how the ingredients fit in.

The process starts with the source of starch – the barley. Barley grows in a field and is harvested (picked), before being dried. In this dried state, barley can look fairly lifeless. The opposite is actually true.

Barley grains have a genetic blueprint that is awaiting to be awaken. In nature, this would happen when it rains – the rain would start to help those grains to grow into seeds and then on to become larger plants.

So how does this all feed into the brewing process?

The brewing process involves soaking the barley grains in water. In effect, that can be seen as replicating the natural effect of rainfall. This soaking of the water kicks off the growth cycle – looking at it in scientific terms, it seems that the starches of the grain are converted into sugars. This conversion is carried out by enzymes and the sugars are vital to the brewing process.

These sugars are then used by the seeds to start growing at quite a pace. The seeds will start to sprout. At this stage, the barley is once again dried in the brewing process.

This may seem like a strange thing to do but drying at this point does not stop the enzymes from functioning – they continue to convert starches into sugars, but without the seeds continuing to sprout.

This is the start of a process known as malting.

So what’s the next stage? The next step is mashing. In this stage of the process, you take the lightly roasted barley (now known as ‘malt’) and mix it with other roasted grains, plus warm water. This produces a sweet liquid that is full of flavour and known as mash.

So we’ve been through the process of malting and then the process of mashing. We now have a warm, sweet liquid. This liquid, known as wort, is then boiled with hops in a vessel called a copper for at least an hour. After boiling, the hopped wort is run over a bed of boiled hops – this acts as a filter.

Our next step is to cool the liquid down and then to add yeast. Yeast is, in many respects, the magic ingredient in the brewing process. Yeast enables fermentation to begin.

Fermentation is obviously critical to the brewing process but what’s it really all about?

Basically, yeast takes in the sugars and some other nutrients from our hops and barley. It then generates two things: carbon dioxide (CO2) and alcohol. There are no prizes for guessing that alcohol is the key component that we’re looking for.

It seems that yeast works best in conditions that are warm and humid. If it’s too warm, however, then you can be left with a beer that doesn’t taste too good.

When fermentation has finished, you are left with “green beer”. This is run into conditioning tanks for a few days.

What about keg beers?

There's a good explanation of the process for keg beers at CAMRA.