In the last installment of “How do I do that?” I described what’s happening chemically during the mash.
This time I need to tell you how to build a mash tun, but that will also require me briefly describing the ways in which you can sparge your mash. Spargeing is just rinsing the grain bed to remove sugars that have been left behind from the mash runoff. This step actually comes after the mash, which seems a bit like putting the cart before the horse.
Why would that matter? Because how you sparge will have a large effect on how you build your tun.
- If you intend to fly sparge — i.e. slowly drizzle water over the top of the grain bed to rinse the grain — you will probably want to build a manifold for your filter.
- If you intend to batch sparge — i.e. drain all of your initial mash liquid and then add your sparge water to rinse the grain — you can save money by building a tun with a stainless steel braid for your filter.
Building a manifold will not negatively affect your results if you batch sparge — in fact I’ve heard reports that it will increase your efficiency greatly — but you shouldn’t fly sparge with a stainless braid filter. More on that later on.
So… since we know what the mash is, we can start talking about how to build a mash tun and why we choose the parts we do for one.
It’s best to use a vessel for the mash tun that will maintain a relatively static internal temperature. It needs to be insulated, and since we’re going to be modifying it a bit, it should be relatively cheap. (more…)