Tuesday 23 September 2014

Mashing in Denmark in 1960

We're getting to the real meat of A. J. Mayfield's article of German and Danish brewing. Stuff about the nuts and bolts of brewing.

Unsurprisingly, Mayfield seems to have concentrated his attention on Carlsberg and Tuborg, at the the time the country's largest breweries.

"Brewing.—Both Carlsberg and Tuborg have recently carried out extensive modernization, and it seems probable that the pattern of large-scale brewing in Denmark has now been set for many years to come. Complete standardization in brew types and sizes has been achieved, with each process timed to fit a given number of brews into the 24-hr. working day.

In the Carlsberg brewery, basic simplicity combined with rigorous control at all stages was striven for and, where possible, a control test with easily reproducible numerical limits was employed. The brewing plant was double as far as the plate coolers, with mashes on alternate sides giving a regular run of worts to the fermenting cellers at 2-hr, intervals. With a separate maize mash, this necessitated a third mash-kettle on each side to hold the mash for the final rest before filtration. Ten beers were produced with gravities ranging from 1026° to 1080°; seven of these were pale types with separate maize mashes, and mashing procedure was arranged to keep the schedule shown in Table I.

TABLE I
Mashing Schedule for Pale Malts Time
Mashing stage (min.)
In-mash malt at 95° F 15
In-mash maize at 124° F. -
Maize to boil 40
Maize boiling 20
2-stage addition of maize mash to malt with 10-min. rest at 124° F then raise to 149° F 35
Saccharification rest at 149° F. 60
Pump off decoction 10
Decoction to boil 25
Decoction boiling 25
Return to head mash, raising temperature to 169° F 15
Rest at 169° F. to complete the mash 25
Total 255


TABLE II
Mashing Schedule for Dark Malts Time
Mashing stage (min.)
In-mash malt at 124° F 15
Pump off first decoction 5
Decoction to boil 30
Decoction boiling 25
Return to head mash, raising heat to 158° F 15
Rest at 158" F. 20
Pump off 2nd decoction 10
Decoction to boil 25
Decoction boiling 25
Return to head mash, raising temperature to 169° F 15
Rest at 169° F. to complete the mash 65
Total 250

The maize mash contained about 25% of highly diastatic malt to assist in starch liquefaction. Dark beers also conformed to the 4.25-hr. timing, but with a single all-malt mash, and a typical schedule is given in Table II."
Journal of the Institute of Brewing, Volume 66, 1960, pages 495 - 496.

Carlsberg was obviously running its brewing kit pretty much non-stop. Having new wort ready every two hours is impressive. That's twelve brews a day.

I'm pretty sure both those methods are double decoction. Using a cereal mash as a decoction is a trick Dann used when brewing Younger's No. 1. It worked remarkably well, with the temperatures coming out spot on. Both methods here have three rests, though not exactly the same temperatures. Not sure why the second rest was warmer for the dark malt schedule.

Now for a really fun topic: milling.

"Milling was performed on 5- and 6-roll mills fitted with vibrating screens which gave a good separation of husk, grits and meal. Roller settings were carefully controlled to maintain an average grits diameter of 0.38 mm., which gave best results for extract and filtration with this plant. The grist cases were suspended on weighing bridges coupled to automatic recorders which gave the weight of malt as ground."
Journal of the Institute of Brewing, Volume 66, 1960, page 496.

I don't feel qualified to make any comment on that.

Now more mashing details:

"For mashing, the required length of liquor was prepared at the prescribed temperature in the kettle, and a simple dry drop of grist was stirred in with the propeller. Temperature recording was continuous on one chart from in-mash to casting, and a master control panel prevented the flow of mash or wort in the wrong direction. The pH was adjusted by standard additions of permanently-maintained lactic mash, followed, if necessary, by a calculated addition of lactic acid; no other liquor treatment was needed for the town's water supply, and the pH of the boiled Pilsner wort was thus maintained between 5.2 and 5.4. With mash-filters for separation of spent grains, a 50-Qr. mash was filtered and sparged in 2.5 hr.
Journal of the Institute of Brewing, Volume 66, 1960, page 496.

Heating the water and then adding the grist is very different from how British breweries usually operated. They would use a Steel's masher - a screw which mixes grain and water in the right proportion as they enter the mash tun. Steel's mashers are still common in British breweries.

Interesting that they sometimes used lactic acid to control the pH of the mash. That's something that wouldn't be allowed in Germany because of the Reinheitsgebot. What is that telling us about Carlsberg's water? That it was soft?

Mmm. I seem to have asked more questions and provided few answers.

Boiling next time.

4 comments:

Oblivious said...

"Interesting that they sometimes used lactic acid to control the pH of the mash. That's something that wouldn't be allowed in Germany because of the Reinheitsgebot.

You can get latic acid from sour mashing/fermentation that is compliant with the Reinheitsgebot.

I have seening a brewer with a lactic product systemt

Jeff Renner said...

Apparent typo you may want to correct - "Rest at 109° F. to complete the mash"

Presumably 109° F.

Ron Pattinson said...

Jeff Renner,

yes, it's wrong. Bad OCR.

Mitchell W Rumpf said...

You had the 2 tables showing the mashing for Pale vs. Dark Malts. You say, "Not sure why the second rest was warmer for the dark malt schedule." The higher rest on the dark is to accentuate the sugars and the pale rest at a lower temp brings out more alcohol in a drier beer.