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Talking of sugar, five different types were used. Though no single beer includes more than three.

Most common is No. 3 invert, which pops up in everything except the Pale Ales. Which makes sense. Though, on the other hand, they do contain black malt. Which makes no sense at all.

Second most popular is malt extract. Which, rather randomly, only appears in the Pale Ales and Milds. Usually, it’s there to deliver extra enzymes. Which makes sense if there’s a large percentage of adjuncts needing to be converted.

No. 1 invert turns up exactly where you would expect: in the Pale Ales. Which is exactly the type of beer it was intended for.

The Mild/Burton parti-gyle includes a small amount of caramel. Though the Porter and Stout don’t. Maybe the high percentage of roasted grains made it unnecessary. Caramel was quite common in these styles. At Fullers, they used two types, for example

I’m guessing OM was some sort of Oatmeal Stout sugar. And it was coupled with the only adjunct: oats. At least I think it’s an adjunct. It could have been malted oats. The record isn’t specific. Compared to other London Stouts, the percentage of oats in the grist is really high. Usually, it was no more than 2% or 3%.

Note that it’s the Pale Ales that contain the most sugar. That was often the case before WW I. When gravities were higher and brewers wanted to keep their Pale Ales, er, pale. Here, that can’t be the case, as there’s also a fair amount of black malt in the mix.
Young's adjuncts and sugars in 1932
Beer Style oats malt extract no. 1 sugar no. 3 sugar caramel OM total sugar
A Mild 2.40% 8.01% 0.70% 11.11%
X Mild 3.00% 6.00% 1.03% 10.03%
XXX Strong Ale 13.13% 0.67% 13.81%
XXXX Strong Ale 13.13% 0.67% 13.81%
PAB Pale Ale 2.86% 11.43% 14.29%
PA Pale Ale 2.86% 11.43% 14.29%
P Porter 7.79% 5.19% 5.19% 10.39%
S Stout 7.79% 5.19% 5.19% 10.39%
Young's brewing record held at Battersea Library, document number YO/RE/1/1.