Monday, 9 March 2009

The colour of malt

Recent recipes have resulted in questions about the colour of crystal malt. I never imagined I'd have discussions about things like this. Most, I'm sure, hoped they never would.

Amber malt and crystal malt are right bastards. As much, in their own way, as brown malt. But let's not get distracted by that. Both amber and crystal malt varied greatly in colour from maltster to maltster.

Amber malt filled almost the whole space between pale and brown in terms of colour. How on earth can we hope to work out what shade of malt the records are talking about? There's no colour indication in the logs.

But . . . . there is a hidden clue. Nothing exact, but a rough guide.

Some logs give the weight per quarter (a volume measure) of the various malts. In general, the darker the malt, the lighter the weight. That's something I learned to take account for in transcribing recipes. Five quarters of pale malt is a lot heavier than five quarters of brown malt.

Do you see where I'm leading? We can make a guess at the colour from the weight (in pounds) per quarter.

To the right you'll see the weight per half quarter of Barclay Perkins malts for the years 1937 to 1939.

Crystal malt has weights of 140, 135, 135, 140, 168, 144, 142, 142, 144.

Brown malt 140, 130, 130, 130, 138, 138

Pale Ale malt 169, 168, 165, 168, 168, 170, 170

(That's for those of you who can't be bothered to look at the images.)

Is this nerdy? Yes, if you're threatened by anyone with knowledge because your own ignorance is so great. Personally, I love a puzzle and a challenge.


Anonymous said...

"...varied greatly in colour from maltster to maltster."

Still does. They argue like crazy. A 130 from French & Jupp isn't the same as a 130 from Fawcetts. Unbelievable eh?

I like your observation about weights though. It is missing calibration however so we don't know how much influence a percentage change in weight makes to colour.

Jim Johanssen said...

Ron - We may not know exactly what the color was just like the IBU issue, but we can get in the ball park, then we can ask which ball park, Basketball or Baseball?
Nice bit about the weight, we should be able to get rough guide for the color.
Do not forget about an adjustment for moisture content if available.