Black Roast Barley

Description

This is unmalted barley that has been roasted at very high temperatures. Black barley is also called dark roasted barley or roasted barley. Although, roasted barley usually refers to unmalted barley with a lighter roast (300 Lovibond versus about 500 for black barley). Black barley imparts dark color and complex coffee-like flavors. These flavors can range from intensely roasty to slightly nutty to burnt or slightly smoky. This grain contributes to the perception of a dry finish.

Black barley is visually quite similar to black patent malt. Both grains are kilned to a high degree, but black patent malt is malted prior to kilning. This makes more sugars available to react with proteins in Maillard Reactions. Products from these reactions can cause the beer's head to appear slightly brown at high concentrations. Therefore, black barley should have less impact on the color of beer foam than black malt. Black barley is also thought to produce rounder more multi-faceted flavors than black malt. Unlike black malt, it has some starch available for conversion in the mash.

An important property of dark grains is that they are slightly acidic. Mashing dark grains lowers the pH of the mash solution. This counteracts the higher pH in groundwater from some locations where there are large amounts of dissolved carbonates. High mash pH, if unchecked, leads to extraction of unpleasant tannins from the grain husks.

In excess roasted flavors can be perceived as burnt and a pleasantly dry finish can morph into back-of-the-throat astringency. When used in large quantities, any of the dark roasted grains (chocolate malt, black patent malt, roast barley, black barley) can become harsh. The total percentage of dark grains is generally low (< 20 %) even in opaque black beers. However, a mild edge of harsh flavors can help structure the flavors in the beer so that there is pleasant tension between contrasts. For example, bitter roast grain flavors can balance malt sweetness very much the way hop bitterness is used in many beers. Consequently, many beers making heavy use of dark grains tend to be more restrained in the use of hops and/or have a healthy dose of crystal malt sweetness.

Black barley is produced in heated rotating drums so that the grains continuously tumble while they roast. Temperatures are high enough that water must be added to "quench" the grains to prevent them from igniting. Some moisture content is necessary for the chemical reactions of roasting. The roasting drums used to kiln black barley are similar to the drums used for coffee roasting. The temperatures used in making black barley (up to 446 °F) correspond to a coffee with a fairly dark roast-level known as Vienna Roast. The flavors of this fairly dark roast coffee have some similarities to the flavors of black barley. Vienna Roast is known as the roast-level where characteristics unique to the geographic origin of coffee are mostly lost behind the roast character. Black barley could have more in common flavor-wise with other roast food products, like coffee and chocolate, than with other barley products.

Beer Styles

Black barley is a key ingredient in most stouts and many porters. It is often the featured ingredient in dry Irish stouts. It can be used for about 5 to 10 % of the grist in these low gravity and minimally hopped ales. Furthermore, it is often the only specialty grain with any noticeable contribution. Due to low hops, the bitterness from roast grains becomes essential. Relatively dry yeast, and possibly some lactic acid tartness, can further accentuate the drying character of this grain. At the source, in Dublin, these beers are made using high carbonate water.

American versions of dry stout often have slightly more hops with slightly higher gravity. They may also feature a more aggressive roasted barley profile. They may use black barley for up to 15 % of the grist. These stronger flavors overall may be balanced against a stronger core of malty sweetness.

Many sweet stouts make use of 5 to 10 % black barley. These less attenuated stouts complement rich sweetness with the espresso-like bite of black barley.

The first porters were made using mostly brown malt, and later a mix of black patent malt and pale malt, but modern robust porters may use a mix of dark grains (including black barley) with a pale malt base. In these beers, black barley can be used to compliment black malt or completely replace it, but it is still usually less than about 12 % of the total grain.

Higher gravity dark beers like imperial stout, Baltic porter, and export strength stout generally use about the same amount of dark grains as lower gravity dark beers. Given larger grain bills this results in a slightly smaller percentage of dark grain.

Very small amounts of black barley can add interesting flavors to nut brown ales and brown porters, but a strong roast flavor is not really consistent with these styles. Black barley produces deep red highlights around the edges in otherwise very dark beers. In minute amounts (1 to 2 %), paired with otherwise pale malts, it produces red-colored ales. It can also be an excellent addition for many medium to dark holiday/specialty beers.

Grain Analysis

Extract Potential 1.023 - 1.027
Color (°L) 500 - 525
DPLin) 0
Protein (%) 13

Statistical values aggregated from [1] and [2].

References

  1. ^ "Grains and Adjuncts Chart." Brew Your Own. http://www.byo.com/resources/grains. Retrieved 2013-11-09.
  2. ^ Briess Malt and Ingredient Co. http://www.brewingwithbriess.com. Retrieved 2013-11-09.
  3. England, Kristen. "Dark Roasted Barley." Brew Your Own. March/April 2008. http://byo.com/stories/item/533-dark-roasted-barley. Retrieved 2013-11-09.
  4. Lewis, Ashton. "The Dark Secrets of Stout." Brew Your Own. January/February 2005. http://byo.com/english-bitter-pale-ale/item/1477-the-dark-secrets-of-stout. Retrieved 2013-11-27.
  5. "Using Sight to Determine Degree of Roast." Sweet Maria's Coffee Library. https://www.sweetmarias.com/library/content/using-sight-determine-degree-roast. Retrieved 2013-11-28.