Let's Brew - 1909 Maclay OMS 63/-

As one of the first Oat Stouts, this is an incredibly important beer. One which inspired a whole generation of beers. This should be interesting.

At just 1062º, it’s not exactly the mightiest of Stouts. It just about scrapes in strong enough for a Single Stout. A pretty poor degree of attenuation – a recurring theme in Scottish Stouts – leaves it only a shade over 5% ABV. Or about the same as a London Porter.

As this was parti-gyled with the DBS which we’ve just seen, I have little to say about the recipe. Other than that, at 20%, the oat content is pretty high. At most brewers, who, admittedly, used flaked rather than malted oats, it was under 5%. Sometimes, not much more than 1%. Purely token amounts. Whereas the quantity of oats in play here would have definitely impacted the character of the finished beer.

The hops are the same as all the other beers. Hallertau from the 1905, Hallertau and 1907 vintages; Californian from 1907, Farnham from 1908 and Worcester from 1905. 

1909 Maclay OMS 63/-
pale malt	7.50 lb	53.10%
black malt	1.50 lb	10.62%
amber malt	0.50 lb	3.54%
malted oats	3.00 lb	21.24%
No. 2 invert sugar	1.25 lb	8.85%
caramel	0.38 lb	2.65%
linseed	0.50 oz
liquorice	0.25 oz
Cluster 120 min	1.00 oz
Hallertau 60 min	1.00 oz
Goldings 30 min	2.00 oz
OG	1062
FG	1024
ABV	5.03
Apparent attenuation	61.29%
IBU	52
SRM	60
Mash at	144º F
after underlet	154º F
Sparge at	170º F
Boil time	120 minutes
pitching temp	60.75º F
Yeast	WLP028 Edinburgh Ale