Last Updated on 21.11.08 Written by Keith Weiland
All Grain also known as Full Mash brewing is not much more difficult than extract brewing or even kit brewing but can take significantly longer - usually 5 hours or more. Once you understand the basic procedure there is not much that can go wrong that would ruin the beer. It may not turn out quite like you expected or like the recipe indicates but you will have a very tasty and drinkable beer at the end of it all. As with all brewing, preparation and cleanliness are the key to success.
At the start of the day (or the night before) gather all of your equipment together and clean it thoroughly, you only need to sanitise your post boil equipment, I.E. everything that will touch the wort after you have boiled it.
Prepare your water either by filtering it or using 1 campden tablet per 5 gallons of water to get rid of chlorine and/or chlormide which can cause a medicinal taste to your beer due to the chlorine reacting with the phenols in the malt, forming chlorophenols. I treat my water with Campden tablets after adding it to the boiler/HLT. Measure your ingredients according to the recipe you are using.
You are either going to have a Hot Liquor Tun (HLT) and a Boiler or one unit that you used for both purposes, for simplicity I am assuming just the latter. You should also have a Mash Tun and a Fermenting Bucket
Fill your boiler/HLT with the Treated water if you haven't already done so and turn it on to start heating the water. You want the water to reach about 74°c or 165°f strike temperature. The ideal temperature may be slightly different for you depending on the ambient temperature and the equipment you are using. You can adjust this through trial and error.
You must calculate the amount of water you need based on a number of factors, those being:
Some of these things you will know and some you will need to discover as you go along, for your first brew you will have to make a few educated guesses.
Your brew length is easy, it will usually be 23lt or 5 gallons or until you increase your brewery size as most home brew equipment is based on 5 gallon brews though it may be less with high gravity beers to enable your mash tun to hold the required amount of grain.
Liquid loss during boil will be determined by factors such as the ambient temperature, how vigorously your boiler boils and the dimensions of your boiler. During your first brew you can calculate this by noting down your pre boil volume and your post boil volume then using this calculation - Boil loss %=100-(post boil volume*100/pre boil volume).
Hops and Trub loss is calculated by subtracting your post boil volume in the boiler from the collected volume in the Fementer. I lose about 2lt to trub on a 5 gallon brew and this is a good figure to use for your first brew.
The size of the grain bill matters as you will lose 1 litre of water for every kilogram of grain so in a typical brew you will lose 5 to 6 litres of water to the grain alone.
Dead Space in the mash tun is calculated simply by filling the mash tun to above the outlet and draining by opening the tap, whatever is left is your dead space loss.
I prepare my mash tun by pouring boiling water around the inside surfaces to bring the temperature up to somewhere near my desired strike temperature so when I add the water to the mash tun it doesn't lose temperature.
*note - This article is a work in progress and is not yet finished.