Something other than Heineken

Only kidding. Of course it's more Heineken stuff. Lots of crumbs of knowledge for me to peck away at.

Lagering times is today's topic. Did I mention before that there wasn't much about them in the records? That's not totally true. There are a few details and dates. Annoyingly, no temperatures are given. My guess us that the lagering tanks would have been filled with the wort at the temperature where fermentation ended. That is 5º-6º C. Then slowly cooled to around freezing.

The pattern is fill the tank, leave it open for a few days, seal it up and finally let the pressure increase. That pressure coming from the continued fermentation while lagering. Fermentation must have occurred as the eventual FG is a good bit lower than at the end of primary fermentation. All, with the exception of Export Pils, lost more than 2º Plato during secondary fermentation.

Is lagering really a secondary fermentation? I suspect not, technically. As it's really a continuation of primary. Who gives a toss about that, really? I've certainly more worthwhile quibbles to waste my time on.

Yet another table showing that fall in gravity I mentioned a short while ago.

Heineken 1935 secondary fermentation
Beer	Racking gravity Plato	FG Plato	Fall Plato
Münchener	6.4	4.0	2.4
Pils	6	3.4	2.6
Export Pils	4.5	2.8	1.7
Bok	8.2	5.6	2.6
Source:
Heineken Brouwjournalen van de proefziederij, 1935 - 1957 held at the Amsterdamse Stadtsarchief, document number 1785-1792.

The lagering times are pretty reasonable. Around 10 weeks for the Piseners and for Münchener more than 17 weeks. Just a shame that there are no examples of the two Lagerbiers. I'd love to know how long they were lagereed.

That's enough fun for today. I've some more numbers that need fiddling with. Though,  as it's not raining, I may nip out for a quick walk and read of Private Eye. That night happen to take me past Ton Overmars. Where I may as well check if they've refilled the shelf with Abt.

Pilsener 11th Jul 1935 Lagering
Step	Date
Filled	20th July
Sealed	24th July
Pressurised	29th July
Tapped	30th Sept
Tasted	26th Oct
Total days	72
Source:
Heineken Brouwjournalen van de proefziederij, 1935 - 1957 held at the Amsterdamse Stadtsarchief, document number 1785-1792, page 20.

Export Pils 18th Jul 1935 Lagering
Step	Date
Filled	26th July
Sealed	28th July
Pressurised	5th Aug
Tapped	1st Oct
Tasted	26th Oct
Total days	67
Source:
Heineken Brouwjournalen van de proefziederij, 1935 - 1957 held at the Amsterdamse Stadtsarchief, document number 1785-1792, page 20.

Münchener 2nd Jul 1935 Lagering
Step	Date
Filled	10th July
Sealed	11th July
Pressurised	15th July
Tapped	9th Dec
Tasted	9th Dec
total days	122
Source:
Heineken Brouwjournalen van de proefziederij, 1935 - 1957 held at the Amsterdamse Stadtsarchief, document number 1785-1792, page 11.