What is it?
Roast Barley imparts a dry, intensely roasted, coffee flavour and is used in Guinness style stouts and strong porters. It is normally used at levels below 1.5% of the grain bill to adjust colour and give a dry clean finish to a beer. If you want to make an authentic dry Irish Stout, then roast barley should be used. It is made from unmalted barley (making it distinct from Black Malt which is made by roasting malted barley). This creates a dry, grain-like flavour with hints of coffee, and produces a beer with a creamy white to off white head. It gives black colour with ruby highlights and the distinct, dry, roasted bitter flavour characteristic of Guinness. It can also be used in very small amounts for colour adjustment in other beers with little flavour contribution.
Roast Barley should make up 3-7% of the grain bill to give a coffee flavour in Porter and Stout and 2-5% in Nut Brown Ales. Chocolate Malt or Black Malt is often used in combination with Roast Barley to obtain specific red or deep brown colours.
Roast barley can also be used in partial mash/extract brews. Simply steep the whole grains in the pan prior to to the boil for around 15 minutes in a muslin bag in water between 155 and 175 ºF (66–79 ºC).
- Dry Irish Stout
- Brown Ale
Roast Barley is one of the very darkest grains used and is characterised by an intense, roast aroma, similar to French roast coffee beans. In fact, roast barley and French roast coffee are actually produced in a similar manner. The unmalted barley grains are churned in a roasting drum and heated nearly to the point of combustion. This product is widely used in the production of dry or bitter Stouts and other dark beers, or for the careful adjustment of Pilsen beer colours.
A slower roasting temperature profile is used to produce Roast Barley but the final temperature is 220°C or even higher, which is achieved by allowing the exothermic roasting reactions to continue after turning off the heat source. The reaction is stopped by spraying with water. Because of the high temperature at the end, colour pick-up at this stage is very rapid and extreme care is needed to prevent carbonisation. Because the roasting process is slightly different from that used for Roast malt and a higher final temperature is used, the balance of pyrazines to pyrroles is different. This leads to a more bitter flavour and the use of the material in the so-called bitter Stouts. With extreme care, it can also be used to colour and flavour Lager beers, but the quantities used are very small.
To produce a black, almost opaque beer, the minimum amount of dark roast barley required is 7% (of the grist). This can be increased up to 15% to increase the roast flavour of the beer. Using more than 10% will give more of a smoky, burnt profile. The higher levels will impart a characteristic that is more common in American microbrewed stouts rather than Irish dry stouts.
Roast barley has an acidifying effect on the mash. Because of this, brewers tend to treat the mash with calcium carbonate to keep the pH in the proper range. The proper mash pH is about 5.2–5.5 for almost all beers. Stouts, due to the dark grains, will tend to be on the lower end.
What are the scales used?
"Degrees Lovibond" or "°L" scale is a measure of the colour of beer. The determination of the degrees Lovibond takes place by comparing the colour of the substance to a series of amber to brown glass slides. The scale was devised by Joseph Williams Lovibond. The Standard Reference Method (SRM) and European Brewery Convention (EBC) methods have largely replaced it, with the SRM giving results approximately equal to the °L.
The Standard Reference Method or SRM is a system modern brewers use to measure the colour intensity of a beer or wort. The EBC convention also measures beer and wort colour, as well as quantifying turbidity (also known as haze) in beer. EBC (European Brewing Convention) is used to indicate colour in malts (and beers). The lower the EBC is, the lighter is the malt (thus kilned for a shorter time). EBC and SRM/°L scales and conversions are available online and usually provide colour swatches to indicate the colour depth that you are likely to achieve from specific malts. Most craft brewers measure the colour of the grain using EBC (European Brewing Convention). The higher the EBC the darker the malt. Other countries may prefer Lovibond (L) or the Standard Reference Method (SRM). There are currently two colour scales in common use: SRM in the US, and EBC in Europe. The SRM (Standard Research Method) scale is based on an older degrees Lovibond scale and for all practical purposes, SRM and degree Lovibond are identical. So to convert SRM to EBC simply multiply by 2. e.g. 4 SRM = 8 EBC. The formula for converting Lovibond to EBC is EBC=(2*Lovibond)-1.2
Why Use Dark Rock Malts and Hops?
The Dark Rock Brewing team are passionate about producing the best quality beers. Their mission is to help you to "Master your Craft" and brew the best craft beers possible. There is no reason why home-produced ales cannot be just as good as commercial equivalents. The key to success is having a wide selection of the best quality and freshest ingredients possible. Dark Rock ingredients are not just great value, they are of the highest quality and always supplied fresh. The team strive to constantly innovate and experiment with new styles and products. Dark Rock also markets top quality all-grain and partial--mash kits which receive fabulous reviews. They are experienced commercial brewers and supply craft micro-breweries and nano-breweries with equipment and ingredients. They also provide training and business development consultancy to scale-up breweries. This experience is channelled into equipping the home craft brewer with the "tools to compete". Use Dark Rock products and you can't go wrong.