Barley is widely produced in Scotland with that from the North being better suited to Scotch Whiskey production and that from the South going into beer. Interestingly, Scotch distillers boil the entire mash instead of extracting the wort from the grains. No hops are grown in Scotland and must be imported, so being the frugal folks they are reputed to be, they used a variety of substitutes including ginger, pepper, spices and aromatic herbs. Quassia, derived from the wood of a tropical plant was used into the 20th century and was also used in medicines and insecticide. One pound of quassia equaled 12 pounds of hops. Economics favored minimal bittering and when Scotland and England joined in 1707, an excise tax on malt was in effect on the English brewers which was greater than the tax on hops. This was not included in the treaty and set the stage for the assertive malt character of the Scotch products. Prior to this, most ale from Scotland was of low gravity while the English porter producers were making a very strong brew indeed. By 1800, Strong Ale's popularity accounted for one third of all production from Scotland. Later in the 19th century the strong ales which were actually known as early as 1578 reached the West Indies and America as well as Eastern Europe and India.
For economic reasons, Scottish brewers sought to expand their product lines and, not being knowledgeable about hard water brewing as in the Edinburgh vicinity, hired brewers from Burton to produce pale ales and stouts which were exported world-wide. Tennent also made export lagers which to this day are more popular than their ales. While Scottish exports are generally regarded as being darker, two 19th century breweries prided themselves on the pale, clear appearance of their brews. The Scotch were the first outside Bavaria to sparge in an effort to gain more extract from the mash. Using a very thin mash at 1.33 qts/pound, and a strike temperature of 180F to 190F in a pre-warmed mash tun resulted in a very high mash temperature, producing an extremely dextrinous wort, characteristic of the style.
W. H. Roberts, an 18th century maltster/brewer, dismisses any hop except Kent. Hops were utilized in a .40 to .70 bittering unit to gravity unit ratio while most English recipes yielded .70 to .90. First-wort hopping was quite popular at the time. Fermenting temperatures also varied widely in the Isles with English worts set at 68F and occasionally as high as 80F while the Scotsmen seldom exceeded 58F and frequently dropped as low as 44F.
Modern examples of strong Scotch ales include MacAndrews, McEwan's, Traquair House and Skull Splitter (from Orkney Island). Scottish style ales are McEwan's Export, Belhaven's St. Andrews and Golden Promise from Caledonia. Local brewpubs offer occasional Scottish ales and even a wee-heavy from time to time.
Roasted barley may be found in more than a few recipes dating back hundreds of years and came into use as a result of the Scotch, wishing to get the most for their buck by picking the grains which floated to the top of the steep tank and roasting them. Today, few brewers use any roasted barley with the preference being for black malt (Traquair House uses it exclusively). Little crystal malt is used since a great deal of caramelization come from the long, vigorous boil. Smoked or peated malt, while quite popular with homebrewers is not found in any commercial product from Scotland.
To brew one of these beers, mash high (155F to 158F) and keep hops low (<55 IBU's for a 1.090 strong ale or 20 IBU's for a 1.040 60/-). Kent Goldings or Fuggles are indicated in a single pitch with some using Northern Brewer, Hallertau or Saaz. Age of the hops does not matter with these brew since there should be zero to very little flavor and aroma hops. Expect to boil off at least 20% of the wort in a vigorous two hour boil. Yeasts are normally used not only for their attenuation and fermenting characteristics, but for the flavors they impart. Scotch and Scottish ale yeasts are most recognized for the flavors they do not impart to the beer. While primary fermentation is usually expected to take three or four days at 65F to 70F, you may find that a primary ferment of three weeks at 52F to 60F and a secondary of six to twelve weeks at 50F may produce better results. I recommend that the starter be pushed to at least four volumes at 62F to 65F. Popular yeasts for this brew include White Labs Edinburgh Ale and Wyeast European, Irish ale, Scottish ale and even American ale, which are very clean. For competition, absolutely zero chill-haze is tolerated, nor very much if any diacetyl, so be certain to ferment completely and keep the bright beer very cold. Serve at 42F to 48F for the best flavor profile. Expectations for finishing should be on the higher side with a 70/- around 1.030 and a wee-heavy as high as 1.045. Lighter gravity brews should last six months while beers above 1.080 should be good for a couple of years.