Using ProMash




So to recap, after working through 'Choose Your Brews' our list of ingredients is:


4.5Kg Maris Otter

250gms Vienna Malt

One 100gms packet of Fuggles hops

One 100gms packet of East Kent Goldings hops

Wyeast 1318 London Ale III

We’ve bought our ingredients, or bought acceptable substitutes. Now it’s time to get familiar with the brewing software that is going to help us turn our shopping list into a proper recipe.


There are a few alternatives out there when it comes to brewing software, but I use ProMash because there’s a free version and I’m a canny Yorkshireman. You can’t store all your recipes on the free version, but that’s no hardship for me because I type them out anyway and keep them in a series of folders along with my brewing notes. (I whip out these folders and show them to guests who have outstayed their welcome; they soon start looking at their watches and reaching for their coats…)

ProMash front.jpg

Once you've downloaded ProMash, take a while to play around with it and get familiar with the functions. Click on 'New Recipe' and play around with the figures and ingredients you can include. It might look complicated at first but you'll get used to it in no time. When you've done a bit of that let's move on to enter our own recipe.

Malt Details

ProMash pick malt page.jpg

 I just use the software to help design the recipe so I don’t bother typing in a recipe name, etc.  Enter the batch size – 25 litres in this case – then click on ‘Malt Name’, then ‘New’. Maris Otter isn’t listed by name (on my version at any rate) so scroll down to ‘Pale Malt (2-row) Great Britain’. Highlight this then click ‘Pick’. Then click ‘Edit’ and change the weight to 4.5Kg.  Click on ‘New’ again, scroll down

the list and choose ‘Vienna Malt Germany’ or ‘France’ – it makes no difference. As before, edit the amount to show 250gms. So now we’ve finished loading up our grain bill into the software. You’ll see the little square marked ‘CLR’ shows us the predicted colour of our beer using these grains in these amounts; and you’ll remember that our beer, according to the guidelines, should be coloured anything from ‘straw’ to ‘golden’.


You’ll also see that the amounts of malt we have decided to use gives us an estimate of what the strength of our beer will turn out to be – in this case, the predicted OG is 1.045. Hopefully the final gravity will get down to 1.010 or 1.012. So, using this formula (OG minus FG X 131.25 = ABV), we can work out that our finished beer will have a strength of something like 4.3% - 4.6% ABV. So we have every reason to believe that our finished beer will fall within the BJCP guidelines of 3.8% - 5.0% ABV. 

So that’s two characteristics of the beer style – colour and strength - we have successfully nailed down.

Hops Details

Click on ‘Hop Name’, then ‘New’ and select the hops we’re going to be using but don’t worry about the ‘Edit’ function until you’ve read this next part…

Alpha Acid Units (AA)

On each and every packet of hops you buy, you’ll see the Alpha Acid (AA) value written in terms of a percentage. This figure is vital when it comes to designing recipes because it tells us how much potential bitterness there is in those hops. Some types of hops have very high AA figures, some very low. And the AA value in any one type of hop doesn’t stay the same; it fluctuates with each harvest and is dependent upon the growing conditions that prevailed that year. Ascertaining the AA value of hops you grow in your garden is difficult and time consuming; if money is no object you can always pay a laboratory to analyse them, but in the real world, not knowing how bitter your hops are is one major drawback to brewing with home grown..


My version of ProMash gives the AA value of Fuggles as 5.0% whereas a homebrew supply shop is selling Fuggles with a current AA value of 3.3%. ProMash gives a value of 4.75 to  East Kent Goldings whereas the current supply is 5.0%. So we now need to go to the software, highlight each hop name, click on ‘Edit’ and update the AA value.  

International Bittering Units (IBUs)

The total bitterness of a beer is expressed in International Bittering Units (IBUs). We can manipulate the total IBUs by playing around with the software, editing the hop schedule, changing not only the amounts of hops we are adding to the boil, but also the timings of the additions (how far into the boil we throw an amount of hops into the pot). As you enter the details – name, weight and when introduced into the boil – of each type of hop into the software, you’ll notice that the total IBUs of the beer are calculated for you. So when to add the hops, and in what amounts?

ProMash pick hops page.jpg

The excellent Beersmith Blog, amongst many others, points out that in blind taste tests beers brewed that have had some hops added at the very start of the boil are regarded as being smoother, and nicely blended, with no harsh bitter aftertaste; so, always put at least some of your hops in at the start. As you’ll probably know, there is a lot of reading online to be had about hops, but put simply, hops added early in the boil add bitterness to the beer; hops added in the last five to fifteen minutes of the boil, although adding a small amount of bitterness, mainly add flavour and aroma.


With all this in mind, we can play around with the software to make sure our hop additions provide the level of bitterness called for in the guidelines (20 – 45 IBUs) and, more importantly, that they provide lots of flavour and aroma. Personally I prefer beers that are on or around 40 IBUs. Feel free to come up with your own combination; it’s fun to mess around with the figures.  

And after having said fun I’ve finally settled on a hop schedule which not only comes close to 40 IBUs but also rather neatly uses up all of the hops we bought. The substantial late additions to the boil will guarantee that we end up with the correct amount of bitterness and the aroma required by the style guidelines. Full details of the hop schedule are given on the next page, 'Bringing It Together'.

Evaporation Rates

I talk about evaporation rates (that is, the amount of liquid lost in the boil) in the ‘Wort Collecting & Sparging’ page. You may have noticed, if you click on the ‘Pre-Boil’ button, that ProMash has an evaporation rate set at 15% per hour. Don’t worry about this; as long as you know your own personal evaporation rate, you don’t need the pre-boil functionality at all.  

Promash evap rate box.jpg

Now all the hard work has been done it’s time to write up our recipe in a format we can easily follow come brew day and this is outlined in ‘Bringing It Together’