In the last article in this series on how do you create a brewing recipe we looked at how to calculate the weight of malt that we would need to use to achieve a target original gravity in what was a very basic beer recipe. If you haven’t read it yet it is well worth reading first before embarking on this next episode. You can access the article by following the link to Part 1 of the series on how do you create a brewing recipe.
If you have read it you will remember we wanted to create a 5% abv ale style beer with a target OG of 1.050. This is all very good if all you want to do is to brew a very basic beer. But as home brewers we like to experiment. So what do you do if you want to add something to your recipe other than just pale ale malt? Say for example you wanted to add a bit of colour to your brew by using coloured malt such as crystal malt. Or how about adding some torrified wheat to improve the head retention of your beer? Fortunately because of our LDK number, or the coarse extract as is, we can start to create a more complicated brewing recipe and use some alternative grain types.
Let us return to our original basic recipe that we used in the last article. If you remember we wanted to brew 25 litres of beer with an original gravity of 1.050. In the original recipe ale malt represented 100% of the grist and we calculated that we needed approximately 4.6 kg with 90% brew-house efficiency. Now I want to get a little bit more adventurous with my brewing and would like to have a bit more colour in my beer. I have also noticed that the beer that I brewed with my original recipe didn’t produce a particularly stable head of foam, and I like a bit of froth on my pint. To rectify the head retention issue I therefore want to put a bit of torrefied wheat into recipe as this should help improve the foam. The first step is to decide the proportion of your extract that is going to come from each of the different grains. For coloured malts such as crystal these are usually added to obtain a particular colour in the final beer. I will not go into how to calculate colour just yet but generally coloured malt does not represent more than 10% of the grist so for this example I think I will add 5% crystal and 10% torrefied wheat should be sufficient to fix my head retention problems.
Having decided the proportions I now know that 85% of my extract will come from ale malt, 10% from torrefied wheat and 5% from crystal malt. If I check my analysis certificates for these 3 ingredients I can see that my ale malt has a coarse extract of 302 lº/kg, torrefied wheat is 280 lº/kg and crystal malt is 275 lº/kg.
To work out the amount of each ingredient required you must work it out as if the individual grain ingredient represented 100% of your grist and then multiply out by the actual percentage used in the recipe. Therefore for the ale malt:
Malt required = (((Gravity – 1) x 1000) x Volume wort required)/ LDK
Malt required = 50 x 25/302
Malt required = 4.14 kg
Malt represents 85% of the grist therefore:
Malt required = 4.14 x (85/100)
Malt required = 4.14 x 0.85
Malt required = 3.52
Now we can repeat this for the torrefied wheat bearing in mind that this time the coarse extract for the wheat is 280 lº/kg:
Torrefied wheat required = (((Gravity – 1) x 1000) x Volume wort required)/ Coarse extract as is
Torrefied wheat required = 50 x 25/280
Torrefied wheat required = 4.46 kg
Torrefied wheat represents 10% of the grist therefore:
Torrefied wheat = 4.46 x (10/100)
Torrefied wheat = 4.46 x 0.1
Torrefied wheat = 0.45 kg.
And finally we can calculate the crystal malt component:
Crystal malt required = (((Gravity – 1) x 1000) x Volume wort required)/ Coarse extract as is
Crystal malt required = 50 x 25/275
Crystal malt required = 4.55 kg
Crystal malt represents 5% of the grist therefore:
Crystal malt required = 4.55 x (5/100)
Crystal malt required = 4.55 x 0.05
Crystal malt required = 0.23 kg.
If you remember this has all been calculated assuming a brewhouse or mashing efficiency of 100%. If we use the brewhouse efficiency that we used last time of 90% then all we do is multiply the calculated weight by 100/90 or 1.11. Therefore for the three ingredients the required weight is:
Ale malt required = 3.52 x 1.11
Ale malt required = 3.9 kg
Torrefied wheat required = 0.45 x 1.11
Torrefied wheat required = 0.5 kg
Crystal malt required = 0.23 x 1.11
Crystal malt required = 0.25 kg
There you have it a brewing recipe for a 5% abv ale style beer using 85% ale malt, 10% torrefied wheat and 5% crystal malt.
Next we will look at how you calculate the quantity of water required to mash.