Late 19th century London Stout mashing

London brewers were certainly keen on their complicated mashing schemes. They may have finally discovered sparging, but there were still multiple mashes.

This example from Barclay Perkins has two full mashes, but also an underlet mash. It was a type of step mash much beloved of English brewers. About 30 minutes after the initial infusion a small quantity of hotter water was added via the underlet, i.e., from the bottom of the tun. The rakes were spun a couple of times to mix the new water well with the grains and left to sit for a couple of hours.

It’s not that dissimilar from the 1849 version. The biggest difference being that the second mash was cooler. And a sparge replace the third mash.

Whitbread were doing something very similar. Two mashes, an underlet mash and a couple of sparges. The tap temperatures for the first and second mashes were very similar at the two breweries.

Barclay Perkins 1899 BSt Ex mashing scheme
action	barrels	strike heat	tap heat
mash 1	64	151º F
underlet	9	166º F	146º F
mash 2	32	170º F	155º F
sparge	32	160º F	152º F
Source:
Barclay Perkins brewing record held at the London Metropolitan Archives, document number ACC/2305/1/594.

Whitbread 1900 S, SS and SSS mashing scheme
action	barrels	strike heat	time mashed	time stood	tap heat
mash 1	540	156º F	30
underlet	50	170º F		75	144º F
sparge 1	300	180º F
mash 2	280	180º F	15	30	155º F
sparge 2		170º F
Source:
Whitbread brewing record held at the London Metropolitan Archives, document number LMA/4453/D/09/094.