Brewers who followed the trend, most likely trying to dodge Maclay’s patent on Oat Malt Stout, usually went for flaked oats. In quantities so small, they could only have been for legal purposes. At no more than 1% of the grist, far too little to have any impact on the character of the beer.
No-one in London set up to brew an Oatmeal Porter. It was simply a side-effect of parti-gyling. As Porter usually shared its grists with the Stouts, there was simply no avoiding it, if you wanted to brew an Oatmeal Stout.
There never seems to have been an attempt to market this by-product. Perhaps because Oat Stout was usually a bottled product. And by this point Porter wasn’t usually bottled. A fact which probably hastened its demise. Stout, for example, managed to survive in bottled form long after draught versions disappeared.
With oats making up less than 1.5% of the grist at Truman, they were pretty typical of London brewers.
|Truman Runner grists 1880 - 1909|
|Year||OG||lbs hops/ qtr||hops lb/brl||pale malt||brown malt||black malt||crystal malt||oats||flaked maize||caramel||sugar|
|Sources: Truman brewing records held at the London Metropolitan archives, document numbers B/THB/C/082, B/THB/C/092, B/THB/C/096, B/THB/C/102, B/THB/C/108 and B/THB/C/112.|
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