Steinecker brewhouse - The three vessels pictured are (from back to front): kettle, mash mixer and lauter tun. The three vessels collectively make up what is termed the "brewhouse". The mash mixer is where milled malt and hot water meet and the two are thoroughly blended. In the mash, enzymes convert malt starches into fermentable sugars. The lauter tun acts like a big sieve and accomplishes the goal of separating liquid (wort) from solid (spent grain). The kettle is where the wort is boiled and also where hops are added in the process.