I am trying to understand the following part of a Gueuze recipe which calls for an Adjunct. The recipe is from the Gueuze-Lambic book by Jean-Xavier Guinard. I like the guy but his recipe is not detailed enough (for me, at least). It says:
“Mix 1.4 gallons of water with the 3.3 lbs of wheat and 10% (0.68 lb) of the klages pale malt. In a cooker, bring to a boil after a ten minute rest at 158F. Boil for 30-45 minutes.”
My question: What exactly do I bring to a boil?, the 1.4 gallons with all the grain in it?, sounds weird to me. Or do I just boil the collected wort after the 10 minutes rest at 158F (but if so, no sparging?).
I assume you’re using unmalted wheat. It look like he’s describing what’s more commonly known as a cereal mash in order to gelatinize the wheat, make the starches available for conversion when added to the mash. And yes, you are correct in that you would be boiling the water and grains.
Bob’s got it right, that’s a standard cereal mash, but indeed with little detail. Here’s the full procedure. The unmalted adjuncts, along with 10% of the total malt, are mashed in at a standard water to grist ratio for a target temperature of 122°F (50° C.) At the same time, the remaining malt (called the main mash) is also mashed in, in the normal fashion, at 122°F (50°C) and held there for a protein rest. The cereal mash, meanwhile, is immediately raised to boiling and boiled for 10 minutes to fully gelatinize the starches (enzymes in the malt aid in liquefaction of the cereal mash, so you don’t just make porridge.) The boiling cereal mash is then mixed into the main mash to bring the entire, combined mash up to conversion temperature (just like a decoction,) and from there, conversion, mash off and sparging proceed as for a normal step mash.
EDIT
(If all that seems like a PITA, it is. That’s why many brewers have long preferred flaked adjuncts, which are pre-gelatinized and can just go into the mash with the malt, over grits. If a recipe calls for grits and a cereal mash, you can just substitute flakes and do a regular infusion or step mash. If there’s a large amount of adjunct, you’ll still want to include a protein rest to ensure sufficient FAN for the yeast.)
Also curious, I looked it up. 1990. But even by then Klages was no longer grown and “Klages” was just homebrew shorthand for 2-row, IIRC. FWIW, I would discard any of those old Classic Beer Styles Series books still lying around. They were mostly wrong when they came out (not always the author’s fault, good info was scarce then) and are utterly outmoded now.
On this note, note this. The book’s description of what clearly should be a cereal mash makes no sense, it appears to be a misplaced description of a decoction procedure from a malt mash. The rest at 158°F can serve no purpose as the adjunct contains no enzymes to convert the starch; that happens later in the combined mash. And in a decoction a long boil develops Maillard products because conversion has taken place. Here there is nothing to be gained from a boil longer than 10 minutes to gelatinize the starches. This is the sort of half-understood information to be expected in old homebrew books (and some newer ones not written by Denny and Drew.) Hope this helps the OP to understand the procedure.
Reading back through the 1977 edition of MBAA’s The Practical Brewer (pp. 70-73.) Says that the malt is rested 15 minutes at 122°F to fully hydrate and liberate enzymes. Then the adjunct is added and simultaneously heat is applied to begin raising to boiling. The starches begin to gelatinize and take on a thick, gel-like consistency. The next action occurs beginning at 185°F, when the starch granules rupture and, in the presence of alpha amylase, disperse throughout the mash and the mash liquefies. Absent alpha amylase, which is still active in this function at this temperature, the gelatinization would proceed to an extreme degree and the resulting gelatinous mass would be unmanageable. The boil is carried out for a length of time dependent on the particular adjunct and determined experimentally, long enough for the liquefaction to become complete, anywhere from 5-30 minutes.
Interesting, for sure. I know that the alpha amylase enzyme denaturing is not a simple switch, but why do we do mash out temperatures of around 170F with normal step mashing (and not higher)? I also know that you must move a bit quickly once that cereal mash is liquefied, as it will return to goo as it cools, if not put back shortly into the main mash.
^^^^
Yep, all gelatinized starches will retrograde – the technical term – at some rate after they drop below their initial gelatinization temperature. We all experience it: it’s the mechanism of staling bread. Stale bread isn’t dry, it can contain the same amount or moisture as when fresh, but the starches go back to being individual grains instead of a smooth mass, making it crumbly.
As for mashing off, I think it’s really more a matter of offsetting heat loss expected when mashing down from the mash mixer to the lauter tun, to ensure a temperature in the goods amenable to good diffusion of extract and quick runoff. Texts usually state that it is only in the boil that enzymes are finally denatured, although they are past their optima at 170°F. Note that British brewers using a combined mash/lauter vessel have traditionally not performed as hot a mash off, presumably because they will not lose heat in a transfer and only need to maintain the optimal runoff temperature in the goods (~163°F,) achieved through the sparge. I think a mash off has other benefits, but that’s me and another topic.
I did find a source that advocates a 30 min. rest at 158°F, having doughed in at 100°F, and possibly a longer boil (determined not by the nature of the starches in the adjunct but the coarseness of the grits, no matter what grain.) It’s the original (1901) Wahl-Henius Handybook. I take this to indicate that this was state of the art practice 120 years ago, still taken for state of the art by at least one homebrew book 90 years later. ;) But does it matter? Just use flakes – that’s what Wahl and Henius really advocated, regarding grits as an outmoded waste of time, energy, and investment in extra equipment.
(I haven’t looked at what procedure Thausing recommends. Don’t feel like squinting at the fancy old German type tonight. And yes, German and Austrian brewers were at the forefront of adjunct brewing.)
Thanks so much Robert and denny, you added a very helpful historical perspective into those old recipes. I am going with flaked adjunct on this one.
FM