Milk stout

The name milk stout refers to lactose, that is, milk sugar. Brewers add it as a sweetener. Brewer's yeast does not ferment lactose, so the beer stays sweet and becomes fuller. The idea of adding lactose to stout was patented in 1908 by the English food chemist William Melhuish. In 1909 Mackeson's in Hythe brewed the first milk stout.

The name does not mean that milk goes in. A British newspaper wrote as early as 1949 that no milk was used in the making, but lactose: a sugar from whey. In the EU allergen list, lactose does fall under 'milk'.

Not every sweet stout contains lactose. The BJCP writes that it is often added, not that it always is. If you are lactose intolerant or drink vegan, take a look at the label.

Lactose in beer is well over a century old. Ordinary sweet stout lost its sweetness as it aged. The English food chemist William Melhuish therefore patented the idea in 1908 of adding unfermentable lactose, so that the stout stayed sweet. In 1909 Mackeson's in Hythe brewed the first milk stout, and the company gave other breweries licences to make one as well.

In 1912 Mackeson won a court case against a London competitor. That competitor sold a 'milk stout' made with milk powder, but with almost no lactose. According to the newspaper report, Mackeson used 9 pounds of lactose per 36-gallon barrel (about 4 kilos per barrel of roughly 164 litres) and had already issued 14 licences. The magistrate ruled that 'milk stout' stood for stout with a considerable amount of lactose, and the competitor was fined.

Modern beers with lactose, such as many pastry stouts, therefore build on an idea from before the First World War.

The colour of beer comes mainly from the grain. The more caramelised, roasted or darkly kilned malt the brewer uses, the darker the beer. CraftBeer.com of the Brewers Association expressly adds that colour does not equal alcohol content or mouthfeel. A quality guide of the Brewers Association for the trade also writes that colour sometimes suggests strength, but often wrongly.

The style guidelines show it in black and white. An Irish stout is black from dark roasted malt or barley, but according to the BJCP has 3.8–5.0% alcohol. A Belgian tripel is deep yellow to light amber and has 7.5–9.5%. The Brewers Association gives the same picture: a dry Irish stout has 4.1–5.3% at a colour of 80+ EBC (black), a tripel 7.1–10.1% at 8–18 EBC (pale). Such a stout does not have to be heavy either: the BJCP calls it remarkably smooth, with a medium-light to medium-full body.

Of course there are also dark beers that are strong, such as imperial stout (8–12% according to the BJCP). That is due to the amount of sugar that was fermented, not to the colour.