Thursday 20 October 2016

Ranking how different factors affect brewing

I've noticed when people get to arguing about how a particular factor affects beer they always seem to go on as if it is of prime importance. I'm not always convinced. For example, home brewers seem to spend an inordinate amount of time obsessing about liquor treatment, when from what I can see ion balance has a relatively minor effect.

So I was pleased to see that in George Fix's Principles of Brewing Science he classifies a number of factors as being of primary, secondary or tertiary importance. Mastering primary effects he says is crucial for every brewer, whereas the secondary and tertiary effects are fine tuning.

Here's his ranking:

Relevance in brewing:




Maillard products
Hops and hop chemistry

Beer clarification
Water chemistry and water treatment

It's interesting to see where he places things, but when I try and slot things in he doesn't list I keep thinking "it depends", with things such as the beer style and if you do get it wrong how badly being variables. Also as he's talking about brewing other important points such as carbonation and the use of sparklers isn't listed. I shall ponder some more.


  1. This is really interesting. We've had a few brewers say to us in interviews something along the lines of 'X isn't the be-all-and-end-all, there are some many factors at play', where X refers to clarity, dispense method, hop variety, and so on. Staleness is the characteristic the other half and I have least tolerance for -- I guess that comes under oxidation in his hierarchy?

  2. Yes, ranked up there as one of the two primary factors. He did also include pre-fermentation oxygenation but definitely the staling effect of oxidation too.

  3. In my home brewing I really don't worry about the chemistry of my water beyond it having two hydrogen atoms to each oxygen. Granted, I am lucky that I have a well and so the extent of my water treatment is a filter, but I haven't actually bothered with finding out the exact mineral content. I think it is on the harder side as it extracts more colour from the malt than the distilled water I used when I lived in town and had a choice between distilled water or chlorinated public source.

    1. Basically brewing liquor advice can be boiled down to get greater that 100ppm of Calcium and less than 50ppm of carbonate. Adjust chloride and sulphate to taste though the effect is minor.

  4. But if you don't have enough calcium or you have too much alkalinity, and that depends on style, you are unable to recover from that later on. Reminds me of old Hi-Fi debates about which component is the most important. Bottom line there was the source, in our game it's the mash, water and it's content is a big influencer.

    1. I'm not saying that liquor treatment isn't important, it's just I think homebrewers tend to attach too much importance to the effects of it.