Patent malt in the early 19th century

Back to malt again. It's fun this, isn't it? This time it's turn of the controversial black or patent malt.

Not all brewers were convinced about black malt. Nor everyone keen in the change it made to the colour and flavour of Porter. I love the description of "nappy brown stout". Doesn't that make it sound yummy? (For my American readers nappy = diaper.)


Patent malt
When all forms of colouring were made illegal in 1816, Porter brewers had a big problem. How could they brew a beer of the right colour when using mostly pale malt? The answer was provided by Daniel Wheeler, who, by roasting malt in a way similar to coffee beans, created a malt capable of colouring a large quantity of wort. Pale malt was roasted at 360 to 400º F in metal cylinders, which revolved over a furnace. (Source: "The Theory and Practice of Brewing" by W.L. Tizard, London, 1846, page 90.) Wheeler acquired a patent for the process, hence the name patent malt. It was also known as black malt, porter malt or roast malt.

Not everyone was a fan of black malt. Tizard wrote "Allusion has been made in former pages to the improvement which has of late years been made in the metropolitan ales, while on the other hand their beers have, in too many instances, declined in virtue and beauty, which circumstance is not wholly, as we have seen, though in part attributable to the introduction of Wheeler's patent malt, or such as is roasted in imitation of it; the "nappy brown stout" produced from amber malt, having fallen off, and in many houses a black sulky beverage being substituted in its stead, on the taste of which the stranger experiences a shake, as sudden and electrical as that which seizes a spaniel when quitting water." (Source: "The Theory and Practice of Brewing" by W.L. Tizard, London, 1846, page 495.)

Because of problems it could cause in the mash tun, black malt was sometimes added in the copper, though that wasn't trouble-free, either. Insoluble parts of the malt could stick to the bottom of the copper and burn or even cause the metal to overheat and crack. (Source: "The Theory and Practice of Brewing" by W.L. Tizard, London, 1846, pages 495-496.) As late as 1933, Barclay Perkins were still boiling some black malt in the copper when brewing their IBSt (Russian Stout).

Black malt varied greatly in quality and colour. Cheaper versions were made from poor-quality barley or had not been properly malted before roasting. (Source: "The Theory and Practice of Brewing" by W.L. Tizard, London, 1846, page 496.) "The colour is often so black that it resembles merer cinders, and the whole corn is puffed up to an enormous size . . . and it adheres together in bunches, through the bursting of the shells and the exudation and fixation of the gummy matter when in the roasting cylinders." (Source: "The Theory and Practice of Brewing" by W.L. Tizard, London, 1846, pages 496-497.) Such malt, beacause it was charred into insolubility, yielded poor colour and flavour. Porter brewed from it would lose much of its colour after a couple of months as the colouring matter precipitated out. (Source: "The Theory and Practice of Brewing" by W.L. Tizard, London, 1846, page 497.)

Properly made black malt had an even chocolate brown colour and its grains did not clump together. Because it had been properly malted, it contained myuch more sugar than the cheap kind. "it contains a much larger quantity of colouring matter of a superior kind, consisting chiefly of caromel, similar to the colouring matter of former times: being burnt saccharum and mucilage, which impart an agreeable odour to the beer, and maintains its colour with tenacity. (Source: "The Theory and Practice of Brewing" by W.L. Tizard, London, 1846, page 497.) Tizard went on to add that all the major London and Dublin breweries used good quality black malt in moderate quantities. (Source: "The Theory and Practice of Brewing" by W.L. Tizard, London, 1846, page 498.)

Due to the problems it could cause in the mash tun, Tizard advised mashing black malt by itself in a special vessel. It could then be mixed with the rest of the wort in the underback. It was mashed repeatedly until all the colour had been extracted. (Source: "The Theory and Practice of Brewing" by W.L. Tizard, London, 1846, page 498.)