Brewing with Dehusked Dark Malt
Whether it was bread or beer that convinced our ancestors to trade in their nomadic wandering to tend fields of grass; grain and human culture are as linked as hops and IPA. From scrawny wild grasses, humans selected for traits that made growing, harvesting, processing, and brewing or baking easier. Slowly, wheat specialized for dough, with lots of sticky gluten and chaff that was easy to winnow. Barley diverged counter for wort production, with lower protein and husks (hulls) that stay firmly attached until milling.
Barley husks continue to be essential to brewing, allowing the grain bed to remain porous for easy separation of wort from spent grain. The husks contain tannins but by controlling the temperature and pH during the sparge, we take care not to extract too much tannin along with the grain’s carbohydrates.
Husk plays two important roles in malt production as well. Low in carbohydrates and high in polyphenols, the husk protects the kernel and creates a different set of flavors than the starchy endosperm. In roasted malts, these flavors provide some of the sharper notes that we associate with stouts and porters. This edge can be delicious but also overwhelming if you desire cocoa and coffee without charcoal and tar. Exactly which molecules impart these specific flavors is unclear. John Mallet, writing in Malt: A Practical Guide from Field to Brewhouse (Brewers Publications, 2015), says: “Husk material contains high levels of astringent tannins, which manifest during roasting.” Stefan Gottschall from Weyermann suggested to me that, “The bitterness is caused mainly by tannins and anthocyanogens, but also from (other) polyphenols.”
Luckily for us, maltsters discovered that removing most of the husk before roasting creates a smoother flavor profile that has subsequently become a classic component of schwarzbier, Czech dark lager, and more recently black IPA. Removing the husk (dehulling) is accomplished in much the same way that brown rice is polished into white rice (and even further into sake rice). Exterior layers are scraped away with an abrasive machine called a decorticator. In the case of Weyermann Carafa® Special, about 40% of the husk remains to protect the interior of the grain during roasting. 1
An alternative to scraping away the husk is to select a variety that has been bred to have a husk that falls away during harvesting. In some cases, wheat (e.g., Weyermann Chocolate Wheat), in others a “hulless” barley (e.g., Briess Blackprinz®). As there is no husk present during roasting, these grains provide the smoothest flavor contribution, but require precisely controlled roasting. 2
What and When
Dehusked roasted malts are typically used when the brewer desires dark color without the harshness of black barley, chocolate malt, or black malt. Sometimes dehusked malts are used for subtle color adjustment, turning a pale beer golden, or adjusting an amber ale into a red. In other recipes they provide a subtle roasted caramel flavor along with a rich dark color that belies the smooth flavor as in a Czech dark lager or Baltic porter. I often include 1% Carafa® Special II in Belgian strong dark ales to impart depth and darkness without overdosing on Special B or dark candi syrup. Dark malts also tend to promote flavor stability during aging by contributing polyphenols with antioxidant properties. 3
As I learned while helping develop the recipe for Modern Times’ Blazing World, the choice of dark malt can have a profound influence on the aging profile of hoppy beers. We initially selected pale chocolate malt, hoping to add both color and toasty depth to the pale and Munich malts without the sweetness of crystal malt. The beer was beautiful the first two weeks on tap, but soon the roast had “eaten” the hops, causing it to shift from a dank-resiny hop-assault into a malty amber. After several pilot batches, we switched to Briess Midnight Wheat, and as a result the hop flavor now lasts much longer (although there are only so many weeks that the intense Nelson Sauvin, MosaicTM, and Simcoe® are at their best!)
These malts can be added as you would any other roasted grain: Steeped in an extract beer, added with the rest of the grain in the mash, or ground fine and added during recirculation or the sparge for a lighter flavor and color contribution.
Cold Steeping
Rather than adding the dehusked malt directly to the wort, make a cold-water extract for an even smoother flavor. In a growler, combine the milled grain with ten times its own weight in chlorine-free boiled and chilled water. After 12–24 hours, strain the mixture through a sieve and then a coffee filter. Add this homemade extract to the wort at the end of the boil, or pasteurize before dosing into fermented beer. This is an easy approach to turn half of a dunkel into a schwarzbier, a standard saison into a dark saison, or the second runnings from a double IPA into a black IPA!
This inky extract can even add fresh roasted character to an aged stout or porter as described in the recipe above (the malt equivalent of dry hopping an aged American barleywine). I used this technique to great effect in a porter earlier this year. I served half of the 10-gallon (38 L) batch on tap, infused with butternut squash, cocoa powder, black treacle, and baking spices while the plain keg sat ignored in my basement. Five months later when show time finally arrived, the beer tasted bland, with the dark fruit of age starting to dominate the roast. After trials with five single dark-grain extracts, I scaled up my favorite combination (equal parts Weyermann Chocolate Rye and Carafa® Special II), filtered, pasteurized, and dosed directly into the chilled keg. The result was like a malted-chocolate shake: Rich, viscous, and amazingly fresh, roasty aromatics!
The Kernel
Familiarize yourself with your roasted-dehusked options: Smell and taste the malts as is, steep them in mash-temperature water for five minutes, or see the sidebar. While their flavor and aroma can be intense undiluted, they are more subdued than their husked counterparts. Consider using them for any recipe where you want color or smooth roast without the harshness associated with roasted husks.
Resources
1 http://www.weyermann.de/in/faq.asp?umenue=yes&
idmenue=62&sprache=2
2 https://byo.com/bock/item/1671-debittered-black-malt
3 http://pubs.acs.org/doi/abs/10.1021/jf051410f
Reanimated Stout
(5 gallons/19 L, all-grain)
OG = 1.066 FG = 1.019
IBU = 29 SRM = 53 ABV = 6.5%
Ingredients
9.5 lbs. (4.3 kg) Irish stout malt
1.75 lbs. (0.8 kg) flaked rye
14 oz. (0.4 kg) Weyermann Caramunich® III malt (55 °L)
8 oz. (0.23 kg) Weyermann Carafa® II malt (425 °L)
8 oz. (0.23 kg) Simpsons chocolate malt (450 °L)
8 oz. (0.23 kg) Simpsons medium crystal malt (65 °L)
8 oz. (0.23 kg) Briess Midnight Wheat malt (550 °L)
2.5 oz. (70 g) Weyermann Carafa® II malt (cold steep)
2.5 oz. (70 g) Weyermann chocolate rye malt (cold steep)
6.4 AAU Sterling hops (60 min.)
(0.75 oz./21 g at 8.5% alpha acids)
Wyeast 1318 (London III) or White Labs WLP022 (Essex Ale) yeast
2⁄3 cup corn sugar (if priming)
Step by Step
Mash at 158 °F (70 °C), adding baking soda if needed to achieve a mash pH of 5.3–5.5. Collect wort and boil for 75 minutes, adding hops as noted. Force chill to 68 °F (20 °C). Transfer the chilled wort to an oversized fermenter. Aerate the wort and pitch the yeast. Ferment at 68 °F (20 °C) until fermentation is complete (about 2 weeks).
Once the gravity stabilizes, the beer is ready to keg. Allow to age in the keg, uncarbonated for up to six months. When ready to serve, crush the cold steep roasted malts (or any roasted malts you enjoy) and combine with 48 oz. (1.4 L) of cool dechlorinated water. Leave at room temperature for 24 hours. Filter through a coffee filter, discarding the spent grain. Pasteurize the ~23 oz. (0.68 L) of inky extract at 170 °F (77 °C); cool and dose into the keg to taste. Seal and pressurize to reach 2.3 volume of CO2, or carbonate and serve on beer gas.
This recipe could be aged in a carboy and then dosed with the cold-steeped dark malt before bottling. Add the cold-steeped dark malt extract a week before bottling to ensure that any trace fermentables contributed are consumed. Aim for 2.3 volumes of CO2.
Partial Mash Option:
Exchange 7.25 lbs. (3.3 kg) of the stout malt for 3.7 lbs. (1.7 kg) of pale dried malt extract or 4.5 lbs. (2 kg) of pale liquid malt extract. Mash only the stout malt and flaked rye during the first 45 minutes of the partial mash, prior to adding the crystal and roasted malts. Follow the remainder of the all-grain version.
Widely Available dehusked roasted malts
Weyermann Carafa® Special I 300–375 °L
Grainy, wood shavings, moderate bitterness
Weyermann Carafa® Special II 413–450 °L
Bread, cocoa, moderate bitterness
Weyermann Carafa® Special III 488–563 °L
Black strap molasses, unlit charcoal, light bitterness
Weyermann Chocolate Wheat 300–450 °L
Chocolate cereal, generic roast, light bitterness
Weyermann Chocolate Rye 188–300 °L
Dark roast coffee, bready, light+ bitterness
Dingemans Debittered Black Malt 500–600 °L
Lightly charred cocoa, moderate bitterness
Briess Midnight Wheat ~550 °L
Dark chocolate, toast, light bitterness
Briess Blackprinz® ~500 °L
Toast, carob, light+ bitterness
To compare and come up with descriptors for the flavors of these dehusked roasted malts, I sat down with a bag of each, a big glass of water, and a notepad.