Author Topic: Reusing 34/70 dry lager yeast  (Read 8806 times)

Offline lupulus

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Re: Reusing 34/70 dry lager yeast
« Reply #60 on: November 27, 2020, 06:35:31 pm »
Re "there is a lot of modern research that renders much of German brewing to the classification of dogma rather than science."

Just for casual readers that happen to read this statement, I wish to state that it's not true at all.

The books, articles and dissertations are widely available.

Prost!

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Offline Saccharomyces

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Re: Reusing 34/70 dry lager yeast
« Reply #61 on: November 27, 2020, 06:58:29 pm »
Just to back track a little about professional literature and suggested pitching temp here is an excerpt from the MBAA Practical handbook For The Specialty Brewer Vol. 2

"(ale) pitching temperature is typically 59°-62°F (15°-17°C), climbing to 67°-70°F (20°-22°C)..."

That is still not lager temperature.  It is just merely cool ale temperature.  The question to ask here is why?  What is gained?  I know what is lost.  The optimal replication temperature for Saccharomyces cerevisiae is 30C.  At 30C, the average replication period is 90 minutes. Every degree below 30C extends the replication period.   

Quote
... and for lager

"Wort is cooled to 45°F (7°C), aerated to a DO content of 8 ppm, and pitched... as the beer ferments, the temperature rises"

First off, fermentation temperature only rises if it is allowed to rise, which applies to both lager and ale fermentation. Are these practices from the days when fermentation temperature could not be precisely controlled; thereby, helping to prevent thermal overshoot?  Secondly, there are two different families of lager yeast with different optimum fermentation temperatures; therefore, this practice is based more on brewing dogma than science, especially in light of recent findings with respect to yeast genetics.   If one reads the publication I linked in my last post, one will see that only the Saaz family of lager strains exhibits significant cryotolerance.  In the case of Saaz strains optimum temperature is 10C/50F whereas optimum temperature for Frohberg strains is 22C/72F, which is at the higher end of normal ale temperatures.  Can we lower the temperature to retard fermentation to reduce growth-related metabolites? Absolutely! However growth-related metabolites are dependent on things other than temperature.  Attributes such as protein content and dissolved O2 enter the picture because higher alcohol production is the result of catabolism of amino acids (the building blocks of protein) via the Erhlich pathway and O2 has an effect of acetic acid production.  That means that treating higher alcohol and ester production as only a fermentation temperature-related problem is akin to treating the symptoms instead of fixing the problem. The carbon to nitrogen ratio of the wort as well as the amount of dissolved O2 have a major impact on higher alcohol and acetic acid production. In essence, high FAN coupled with low O2 is recipe for hot tasting, estery beers.  Fermenting at lower temperature to control higher alcohol and ester production is akin to putting a band-aid on a sucking chest wound.  If anyone wants to test this phenomenon, formulate two non-excessively hopped beers at a gravity of 1.060 (i.e., the malt and hops need to be in balance).  The first beer should be all malt.  The second beer should contain 20 to 30% flaked maize.  The all-malt beer is splash aerated.  The adjunct beer is venturi or direct O2 injection aerated.  One will have to adjust the hopping rate down on the adjunct beer to accommodate for its lighter body.  Both beers should be pitched with the same culture at the normal fermentation temperature for the given yeast culture.  The goal here is not to produce two identical beers.  It is to compare higher alcohol (hot flavors) and ester production between two different carbon to nitrogen ratios coupled with two different dissolved O2 levels.

From https://ec.asm.org/content/13/10/1256:

Quote
Lager yeast strains can be divided into two groups, Saaz/Carlsberg and Frohberg. This division is based on the geographic heritage of the strains and was supported by molecular analyses of transposition distribution in these strains (24). Only recently, the differences in fermentation performance of these two groups were analyzed. It was shown that group I/Saaz yeasts are better adapted to low-temperature growth conditions (10°C), while group II/Frohberg yeasts ferment better at a higher temperature (22°C). Differences in sugar utilization became apparent, as group II yeasts utilize maltotriose and group I yeasts do not. Additionally, flavor differences were identified showing that Saaz strains produce several fold-lower levels of, e.g., isoamyl acetate (banana flavor) than Frohberg strains (25, 26).

What is interesting is that Saaz strains do not ferment maltotriose.  They are also bigger producers of isoamyl acetate.

The MBAA recommendation is more than likely based on the fact that the American lager brewing industry was made possible by Emil Hansen generously sharing Carlsberg Unterhefe No. 1 (a.k.a. Sacchormyces Carlsbergensis) and the Carlsberg flask for pure culture propagation.  The Midwestern brewing industry was built on Carlsberg Unterhefe No. 1, which lives on today as Miller's lager strain (a.k.a. Wyeast 2042 Danish Lager).  Carlsberg Unterhefe No. 1 is the type strain for the Saaz family.
 

Offline hopfenundmalz

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Re: Reusing 34/70 dry lager yeast
« Reply #62 on: November 27, 2020, 07:04:10 pm »
With regards to scales involving temperature, there is a reason we have kept the Fahrenheit scale. It is far finer, i.e., more accurate than Centigrade / Celsius.
All of us (in the USA) grew up with F. It is my standard temp of reference. All pitching temps with regards to W-34/70, and fermentation are referenced in F.
We are all free to use the scale we prefer...at least for the time being.
Re: precision. There is nothing stopping a person from using one or more digits to the right of the decimal point when measuring temperature in Celsius.

Correct. If I switch a digital thermometer from C to F, does it become more accurate? No.

My point is Fahrenheit is a finer scale, and most often does not require the use of fractions to accurately depict the correct temperature, unlike C.

This will help illustrate...I flew B-777's for a major US airline. Internationally, around the world. All of our performance data such as take off performance, climb performance, etc., was based on using Fahrenheit as it is a finer scale avoiding the need for fractions.

That means your pressure reading were in KPA? A tire example, 32 PSI=220.6 kPA, so a finer scale.

I used SI (metric) units at work. Got used to many and could go back and forth. Never got intuitive with pressure.

If you flew an Airbus would it be in degrees C? I'm honestly curious.

Edit.
A little Google time answered my question. Aviation uses USCS units due to the Weight Brothers, and how the US had influence after WWII. Airbus probably uses USCS in the cockpit.
« Last Edit: November 27, 2020, 07:30:40 pm by hopfenundmalz »
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Offline Saccharomyces

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Re: Reusing 34/70 dry lager yeast
« Reply #63 on: November 27, 2020, 07:31:23 pm »
Re "there is a lot of modern research that renders much of German brewing to the classification of dogma rather than science."

Just for casual readers that happen to read this statement, I wish to state that it's not true at all.

The books, articles and dissertations are widely available.

Prost!

Sent from my SM-G960U using Tapatalk

The problem here is that a sizable percentage of German publications are only available in German.  The paper I linked was written by a recognized authority on lager yeast genetics who just happens to be German by birth.  His work on lager yeast genetics is being used by other scientists to push the outside of the evenlope.  Pretty much everything I post here is backed by peer-reviewed science, which I routinely check to see if it no longer holds. I am never going to rely on dogma, as dogma defines a way, not the only way to achieve a result.  Plus, dogma limits one's horizons.


Offline Saccharomyces

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Re: Reusing 34/70 dry lager yeast
« Reply #64 on: November 27, 2020, 07:38:35 pm »
I used SI (metric) units at work. Got used to many and could go back and forth. Never got intuitive with pressure.

Engineers in the automotive industry had no choice, but to become fluent in SI units because the automotive was an early adopter of the metric system.  America will eventually adopt the metric system or risk being isolated from the world.  We are already a mixed country when it comes to units of measure.

Offline lupulus

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Re: Reusing 34/70 dry lager yeast
« Reply #65 on: November 27, 2020, 08:01:49 pm »
Re "there is a lot of modern research that renders much of German brewing to the classification of dogma rather than science."

Just for casual readers that happen to read this statement, I wish to state that it's not true at all.

The books, articles and dissertations are widely available.

Prost!

Sent from my SM-G960U using Tapatalk

The problem here is that a sizable percentage of German publications are only available in German.  The paper I linked was written by a recognized authority on lager yeast genetics who just happens to be German by birth.  His work on lager yeast genetics is being used by other scientists to push the outside of the evenlope.  Pretty much everything I post here is backed by peer-reviewed science, which I routinely check to see if it no longer holds. I am never going to rely on dogma, as dogma defines a way, not the only way to achieve a result.  Plus, dogma limits one's horizons.
Contrary to a few incorrect comments in homebrew forums, there's zero dogma in german brewing.
Thermal load on boiling, low oxygen mashing, endosperm mashing, pressure fermentation have been incorporated to large scale brewing by germans. German brewing technology dominates brewing equipment world wide. There's no dogma there.

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Offline hopfenundmalz

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Re: Reusing 34/70 dry lager yeast
« Reply #66 on: November 27, 2020, 08:03:07 pm »
All of us (in the USA) grew up with F. It is my standard temp of reference. All pitching temps with regards to W-34/70, and fermentation are referenced in F.

I do not know where you grew up, but I was taught the metric system in junior high school (what is referred to as middle school these days) in the seventies in preparation for the U.S. to move to it. However, the movement fizzled out (does anyone remember speed limit signs and speedometers in metric and U.S. customary units of measure).  The reality is that the U.S. has not been a pure U.S. customary units of measure country for the better part of five decades.  Legal alcohol has not been sold in U.S. customary units since 10/1/1976.  For example, the fifth was replaced with a volume of 750ml.  The quart was replaced with the liter. What is referred to as a pint today is actually 375ml (12.68 fl. ozs).  A half pint is 200ml (6.76 fl. ozs).   Non-alcoholic beverages are mixed U.S. customary units and the metric system.  Bottle sizes less than a liter are sold in ounces.  Bottle a liter and above are sold in liters.  Automobiles use a combination of U.S. customary units and metric. 

A lot of Americans refer to our system as imperial units of measure.  However, that is only partially correct.   A U.S. inch is equal to an imperial inch.  However, a U.S. fluid ounce is not equal to an imperial ounce.  A U.S. fluid ounce is 1.04084 imperial ounces.  What we refer to as a barrel of beer today actually started out as a wine unit of measure; namely, the Queen Anne barrel.  Our gallon size is actually the Queen Anne gallon, which is why it is different than the imperial gallon.  A Queen Anne barrel is 1/8th of a tun, which is 252 Queen Anne gallons. 

The reality is that U.S. customary units are an incoherent hodgepodge. The only reason Americans understand U.S. customary units is because they are raised with the system and most only know a fraction of it.  Weight and volume are disconnected, which is why most lab work is performed using the metric system.  The U.S. had the opportunity to be the second country to adopt the metric system and Thomas Jefferson passed because it was a French creation that he found to be too decimal (base 10), which is weird because he created the first base 10 currency in the world.  If want to talk about accuracy, the metric system blows U.S. customary units of measure out of the water precisely because it is base 10.  For example, what base is U.S. liquid volume?  A quick look at the units of measure for a sub-fluid ounce will demonstrate how much of a mess our system is with respect to metric system.  A dram is 1/8th of a fluid ounce. Really?  That makes absolutely no sense once one realizes that most Americans are only taught base 10 arithmetic. Few people outside of computer scientists, computer engineers, mathematicians, and other select engineering types can work in any numerical base other than 10.

Vehicles are engineered in metric now. The instrument panel on my vehicle can be changed to metric by selection in a menu. That was nice crossing into Canada on the way to the Portland homebrewcon to visit friends there.

Vestiges of US units still remain. Wheel size is in inches, while the tires are specified in metric.

One VP said at a presentation that there are universal constants such as, the speed of light, Avogadros number, and the bore spacing of a Chevy Small block V-8 (4.40 inches). Change the bore space and much of the production line would be scrapped.

Newer engines have metric bore spacing, bores to and so on.
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Offline denny

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Re: Reusing 34/70 dry lager yeast
« Reply #67 on: November 27, 2020, 08:16:20 pm »
Re "there is a lot of modern research that renders much of German brewing to the classification of dogma rather than science."

Just for casual readers that happen to read this statement, I wish to state that it's not true at all.

The books, articles and dissertations are widely available.

Prost!

Sent from my SM-G960U using Tapatalk

The problem here is that a sizable percentage of German publications are only available in German.  The paper I linked was written by a recognized authority on lager yeast genetics who just happens to be German by birth.  His work on lager yeast genetics is being used by other scientists to push the outside of the evenlope.  Pretty much everything I post here is backed by peer-reviewed science, which I routinely check to see if it no longer holds. I am never going to rely on dogma, as dogma defines a way, not the only way to achieve a result.  Plus, dogma limits one's horizons.
Contrary to a few incorrect comments in homebrew forums, there's zero dogma in german brewing.
Thermal load on boiling, low oxygen mashing, endosperm mashing, pressure fermentation have been incorporated to large scale brewing by germans. German brewing technology dominates brewing equipment world wide. There's no dogma there.

Sent from my SM-G960U using Tapatalk

It may be scientific dogma, but it's still dogma.
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Offline beerphilmcd

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Re: Reusing 34/70 dry lager yeast
« Reply #68 on: November 28, 2020, 12:17:14 am »
I’ve run into problems with mangrove jack yeast producing terrible amounts of phenolic when repitched. For instance liberty bell is beautiful on the first pitch but turned my time tested blonde ale into a Belgian.

I learned this because I’ve repitched other yeast, dry and liquid, multiple times with nothing but positive results! I’ve ran Nottingham through 7 repitches and have  only had good repeatable results.


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Offline Northern_Brewer

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Re: Reusing 34/70 dry lager yeast
« Reply #69 on: November 28, 2020, 08:17:12 pm »
In British brewing it's historically always been the norm to pitch fairly cool and then let it free-rise - and since cooling became available, then to come down again a bit towards the end of fermentation to stop the bugs cleaning up too much.

But if you look at the British commercial recipes on Ron Pattinson's site, you'll see that almost all of them are pitching in the 59-63F range (including the Scottish ones, they're not pitching at near-lager temperatures as some conventional wisdom would make out).

Bingo!  Most of the ale strains that Americans use originally came from the UK where they were selected under pressure over hundreds of years sans fermentation.  If the mixed cultures from which modern ale strains of British were isolated did not perform well at between 18 and 22C, they would have been discarded.  Lager brewing is a completely different kind of brewing with its own set of rules.  Lager ale cultures were not originally cropped from the top.  The practice of top-cropping is what allowed ale brewers to separate domesticated yeast from wild yeast and bacteria because wild yeast and bacteria do not floc to the top.

Except we weren't talking about top-cropping and lager versus ale, you made the general comment :
I have not found a single reference to pitching below fermentation temperature outside of the amateur brewing forums.  Most professional references I have seen state to pitch at fermentation temperature or a few degrees higher.



However, at least the UK is making an effort to bring your units of measure in line with the rest of the world.

Meh - not really, it was a big deal thirty+ years ago but there's not been a huge effort since we settled on the current system of exempting miles and beer-pints, but metric for everything else, which seems pretty stable. It's only an issue for the boomers who have now pretty much left the workplace, so it only crops up in minor things like "Brexit will allow us to buy carrots by the pound and no longer by the kg".

The Midwestern brewing industry was built on Carlsberg Unterhefe No. 1, which lives on today as Miller's lager strain (a.k.a. Wyeast 2042 Danish Lager). 

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.

You have helped my argument. Why use decimal points, when whole numbers are readily available?
Again...it's my personal hangup. For those who prefer C to F, with the required fractions, knock yourself out.

Why use a 100's column, when you can go all the way up to boiling point of water without it? And how many times do you need the extra precision of whole-number Farenheit, but are not in a position to record or measure centigrade? It's not like say the difference between an inch and a cm, where ordinary people have a good feel for quite small differences in length, people are not good on small differences in temperature. For most purposes centigrade has appropriate resolution.

Offline Saccharomyces

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Re: Reusing 34/70 dry lager yeast
« Reply #70 on: November 28, 2020, 09:26:22 pm »
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, but W-34/70 is the Frohberg type strain (it is originally from the Frohberg brewery in Grimma, Saxony); however, it is listed as a Saaz strain on Langdon's spreadsheet. Jürgen Wendland and his team at Carlsberg Laboratories took W-34/70 apart genetically as few years ago.  If any institution is familiar with Saaz strains, it is Carlsberg Laboratories because CBS 1503, CBS 1513, and CBS 1538 are all Saaz strains that were isolated by Emil Hansen.  CBS 1513 is Carlsberg Unterhefe No. I and CBS 1503 is Carlsberg Unterhefe No. II.

From https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4187645/:

Quote
Lager yeast strains can be divided into two groups, Saaz/Carlsberg and Frohberg. This division is based on the geographic heritage of the strains and was supported by molecular analyses of transpositon distribution in these strains (24). Only recently, the differences in fermentation performance of these two groups were analyzed. It was shown that group I/Saaz yeasts are better adapted to low-temperature growth conditions (10°C), while group II/Frohberg yeasts ferment better at a higher temperature (22°C). Differences in sugar utilization became apparent, as group II yeasts utilize maltotriose and group I yeasts do not. Additionally, flavor differences were identified showing that Saaz strains produce severalfold-lower levels of, e.g., isoamyl acetate (banana flavor) than Frohberg strains (25, 26).

Ploidy determination of hybrid lager yeast strains has been a long-standing issue. Some advances came from a study using array-CGH and DNA sequence analysis covering several lager yeast strains (reference 12 and references therein). A 1n ploidy difference between group I and group II lager yeasts was identified. However, according to this study, group I yeasts appeared to be 2n and group II yeasts appeared to be 3n. Aneuploidy of lager yeasts and regions with copy number variations were also detected in another study using microarray hybridization (27), but only recently was it shown that, based on next-generation sequence and flow cytometry data, Saccharomyces carlsbergensis (group I) is essentially triploid, whereas the Weihenstephan 34/70 strain (group II) is (allo)tetraploid (26). Other studies were based on copy number variations in different strains, which also provided an estimate of the allotetraploid nature of group II lager yeasts (8).

If you noticed, Frohberg lager strains are not as cryotolerant as Saaz strains.  That is why W-34/70 is so forgiving at fermentation temperatures that we normally associate with lager brewing.  The fact that Frohberg strains can ferment maltotriose and Saaz strains cannot is probably the easiest test to check if a lager strain is Frohberg or Saaz just like the presence of absence of melibiose in a beer is a way to test if it is an ale or a lager.


With that said, a lot of Wyeast data is either wrong or we are associating the wrong source cultures with the Wyeast cultures.  For example, here is a description for Wyeast 2124, which most brewers assume is W-34/70.  However, if that is true, then the data below from Wyeast's website is wrong.

Quote
STRAIN: 2124
Bohemian Lager

Species: Saccharomyces pastorianus

Profile: This Carlsberg type yeast is the most widely used lager strain in the world. This strain produces a distinct malty profile with some ester character and a crisp finish. A versatile strain, that is great to use with lagers or Pilsners for fermentations in the 45-55°F (8-12°C) range. It may also be used for Common beer production with fermentations at 65-68°F (18-20°C). A thorough diacetyl rest is recommended after fermentation is complete.

Metric Temperature Range: 8-22 °C
This Carlsberg type yeast is the most widely used lager strain in the world. This strain produces a distinct malty profile with some ester character and a crisp finish. A versatile strain, that is great to use with lagers or Pilsners for fermentations in the 45-55°F (8-12°C) range. It may also be used for Common beer production with fermentations at 65-68°F (18-20°C). A thorough diacetyl rest is recommended after fermentation is complete.
« Last Edit: November 28, 2020, 11:16:38 pm by Saccharomyces »

Offline Saccharomyces

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Re: Reusing 34/70 dry lager yeast
« Reply #71 on: November 28, 2020, 09:46:33 pm »
It may be scientific dogma, but it's still dogma.

I am assuming the lupulus is German.  The German population, as a whole, is very dogmatic.  They have rules and laws that would drive the average American crazy.  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.

Here is Webster's definition of Dogma:

1a : something held as an established opinion especially : a definite authoritative tenet

b : a code of such tenets pedagogical dogma

c : a point of view or tenet put forth as authoritative without adequate grounds

2 : a doctrine or body of doctrines concerning faith or morals formally stated and authoritatively proclaimed by a church


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Re: Reusing 34/70 dry lager yeast
« Reply #72 on: November 28, 2020, 09:48:47 pm »
It may be scientific dogma, but it's still dogma.

I am assuming the lupulus is German.  The German population, as a whole, is very dogmatic.  They have rules and laws that would drive the average American crazy.  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.

Here is Webster's definition of Dogma:

1a : something held as an established opinion especially : a definite authoritative tenet

b : a code of such tenets pedagogical dogma

c : a point of view or tenet put forth as authoritative without adequate grounds

2 : a doctrine or body of doctrines concerning faith or morals formally stated and authoritatively proclaimed by a church

No, I don't think he is.
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Offline hopfenundmalz

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Re: Reusing 34/70 dry lager yeast
« Reply #73 on: November 28, 2020, 11:12:19 pm »
It may be scientific dogma, but it's still dogma.

I am assuming the lupulus is German.  The German population, as a whole, is very dogmatic.  They have rules and laws that would drive the average American crazy.  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.

Here is Webster's definition of Dogma:

1a : something held as an established opinion especially : a definite authoritative tenet

b : a code of such tenets pedagogical dogma

c : a point of view or tenet put forth as authoritative without adequate grounds

2 : a doctrine or body of doctrines concerning faith or morals formally stated and authoritatively proclaimed by a church

No, I don't think he is.

He is not German, but knows a fair amount about German brewing.
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Offline Saccharomyces

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Re: Reusing 34/70 dry lager yeast
« Reply #74 on: November 28, 2020, 11:15:34 pm »
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.
« Last Edit: November 28, 2020, 11:18:02 pm by Saccharomyces »