Author Topic: Reusing 34/70 dry lager yeast  (Read 8808 times)

Offline lupulus

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Re: Reusing 34/70 dry lager yeast
« Reply #75 on: November 29, 2020, 12:00:50 am »
The German law/rule that blew my mind is known as "Abgeschlossene Ausbildung."   What it means is that one cannot just change careers.  One has to go through a formal program of study to change careers.  I learned about it because I used to hang out on a lutherie forum.  A really talented German luthier could not call himself a luthier in Germany because he was self-taught.  PRS Guitars would have never gotten off of the ground if the U.S. had a similar career-limiting law.

Something to consider (not a defense of the system):
Education is almost free in Germany. Changing careers is a cost for those who don't go to College. It's an efficient system.
Won't get into the history, but nowadays the Ausbildung system is a buffer against uncontrolled immigration. A citizen of any EU country can work in Germany, but they need to learn German and do the Ausbildung, limiting the number of non-college immigrants.
Taxes are very low if you compare the perks that you get vs. the US. Health insurance, paid job retraining if you lose your job among others.
Not sure about not changing careers. It is correct for college vs. non-college; you cannot change paths, and not everyone can go to college (related to grades).

“The good thing about science is that it's true whether or not you believe in it.”  Neil deGrasse Tyson

Offline lupulus

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Re: Reusing 34/70 dry lager yeast
« Reply #76 on: November 29, 2020, 12:10:48 am »
It appears that the Kunze text was first published in 1961 and it appears that texts written by Narziss are not quite as old, but are all old in terms of brewing science.  All of these texts were written before genetic sequencing, which means that anything related to yeast is based on outdated scientific information.  I am not attempting to take anything away from these brewing scientists.  They were accomplished in their day, but brewing science is not static.  To treat what they wrote as gospel in light of what has been learned in just the last ten years is, in fact, dogmatic.  The methods that they developed were based on the science of the day.
Books are summaries/ a reset of the current knowledge (as I am sure you know :-) ).
Narziss is a Professor Emeritus at Weihenstephan. The most recent book from the Weihenstephan school is that of Werner Back, still a professor at Weihenstephan.  As a research group it's probably the largest in the world. They publish mostly in "Brewing Science" but occasionally in English and American journals. 
Prost !
“The good thing about science is that it's true whether or not you believe in it.”  Neil deGrasse Tyson

Offline Northern_Brewer

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Re: Reusing 34/70 dry lager yeast
« Reply #77 on: November 29, 2020, 12:31:34 am »
Except that 2042 is a Frohberg according to Langdon et al's lager sequencing paper last year (see Supplementary Dataset 1) - in fact they reckon all mainstream homebrew yeasts are Frohberg.

That is interesting because Wyeast 2042 has always been referred to as Miller's strain and Miller was one of the Midwestern brewers who employed Carlsberg Unterhefe No. I and the Carlsberg flask. I hate to tell you, but Langdon's data is suspect. It could just be a reporting error

All these big sequencing papers are bound to have the odd mistake in - the 1002 Genomes paper looked like they'd mixed up Artois and Orval. That's why I was careful to phrase it as "according to Langdon et al".

OTOH, the Hittinger lab are not amateurs, I suspect they're actually throwing some subtle shade as they have two entries for 34/70, on row 65 they have "W34-70" as Frohberg based on their own Peris & Langdon et al. 2016 paper and marked as "Weihenstephan 34/70" perhaps suggesting they got it direct from Weihenstephan. You're looking at row 53 where they are quoting a "W34-70" from Okuno et al. 2016, maybe Suntory have had a mixup in their library? Yes of course it's bizarre for a 34/70 isolate to be coming up as Saaz.

Edit - I've just noticed there's also a "WS3470" Frohberg in row 55 from van den Broek et al. 2015 at Delft. You'd hope they know their Saazes from their Frohbergs given that the authors on that paper include Jan-Maarten Geertman of Heineken, hypothesised to be the original source of the entire "Frohberg" lineage.
« Last Edit: November 29, 2020, 11:54:45 am by Northern_Brewer »

Offline TXFlyGuy

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Re: Reusing 34/70 dry lager yeast
« Reply #78 on: December 01, 2020, 02:35:57 pm »
I decanted about two pints of beer off my harvested W-34/70 (7th Gen), then added one quart of fresh wort. Shook it up to get it aerated, and it appeared to be coming back to life. The color went from off gray back to it's light peanut-butter like color. The aroma was nice and clean, so it was pitched into a 10 gallon batch of Munich Helles. 1 pint per 5 gallons.
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Offline HopDen

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Re: Reusing 34/70 dry lager yeast
« Reply #79 on: December 10, 2020, 09:41:42 pm »
I decanted about two pints of beer off my harvested W-34/70 (7th Gen), then added one quart of fresh wort. Shook it up to get it aerated, and it appeared to be coming back to life. The color went from off gray back to it's light peanut-butter like color. The aroma was nice and clean, so it was pitched into a 10 gallon batch of Munich Helles. 1 pint per 5 gallons.

Nice!! Keep it going as many generations as you possibly can. Nice money saver to say the least!