Sunday, March 19, 2017

Brew Day of Long Mashing

Today was a brew day, and on deck was a sour beer in the Belgian Lambic style, but first a word about the brew system.  The stainless kettle on the right has a PID controlled 5 kW element heating it, and clean water is circulated through the "outside" of a counterflow chiller (or in this mode, counterflow heater.)  Let's just say heat-exchanger.  The blue mash tun on the left has a false bottom and circulates wort through the inside of the counterflow, bringing it up to the temperature in the heated kettle, hopefully close to the set point on the controller.  This is my conception of the classic "three vessel system" with just two vessels, except for the fact that I use the red cooler on the bottom as a sparge vessel, so it *is* three vessels, but one of them is totally passive.

 Here's another shot showing the exhaust fan to try and help take some of the steam out of the room through an adapter to the dryer vent.  Technically I can't really brew and do laundry, but those are the sacrifices we make.
 On to the beer!  Grain Bill:

3 lbs Raw Wheat
5 lbs Pale Malt

Lambic grain bills tend to use 30% - 40% raw wheat, and I liked this because it is a nice 3/8:5/8 ratio (37.5% wheat.)  I think I was also supposed to use Pilsner as the base malt, but oh well, there will be a next time.  It was hopped with Williamette, 2.5 oz at 120 minutes.  Lambics are supposed to be made with aged hops, so these were in a paper bag on top of the furnace for about a week.  Probably not aged enough, and the wort does taste hoppier than I wanted, but hopefully it will fade in the finished product.  It came out looking great after a vigorous boil, with a dark blond color and crystal white head.

Here's the brew day schedule, which is a nice addition to what I usually do, i.e. unrecorded chaos.  It's a little hard to read, but the basic rundown is dough-in at 111 °F.  This is really low, but there's a ton of raw wheat to work on, and you're supposed to do a turbid mash to lock in some starch to feed the wild microbes.  Then an 11 degree step-up every 15 minutes until you get to 166 °F, mostly because I liked the numerology of 111, 122, 133, 144, 155, and 166.  I let it go a full half hour at 166 °F, and by the time I started sparging, it had been a full two hour mash; you're looking for tannin extraction in a sour.  The boil was also two hours, to really cook things out and concentrate sugars.  All in all, it took 5 hours, but considering the double mash and double boil, I am really pleased with the time efficiency of this system.  Having all the right tubes in all the right places really helped.