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You are here: Home --> Forum Home --> Brewing Forum --> Brewing Discussion --> on tasting

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ingoogni
nl
314 Posts


As kids we always had a lot of fun when my grandmother stayed at our place, she did so twice a year for a week. We played strange games, we'd put stuff in a box with a small opening and she would have to smell and tell us what it is. Being kids, old socks went in the box, dried pigs ears the dog chewed on, soil, leaves, flowers, anything. She was a Grass trained 'nose' and could tell exactly what it was in the box. She could analyse a perfume to it's components and roughly quantify the ratio. She never made a perfume, analysis was her job, not composition. (Sadly I didn't inherit her nose, but later in life happened to do the same thing with my eyes as colourist)

Our home brewers guild has a brewing competition every year. Judging is done by the members, always a fun evening. Judging is also done by the "noses" of the big  brewer in town, Grolsch. They know nothing of styles. They are trained in just one thing, qualification of certain (up to ~40 different) substances and for the best among them also quantification. They judge on brewing quality and then have to compare their findings with style sheets. As everybody has a different 'resolution' in perception of the different substances they always work in teams each member filling their list with check boxes. Evaluation of the gathered data is not done by them.

Many moons ago I worked in the field of "critical dimension metrology" at the time when the semiconductor industry went submicron. One of the biggest influences on the quality of the gathered data where guys who did the measurements. After a lot of work with statisticians, the best way was to give the person who did the measurements as little information as possible, certainly no sheets with dimensions etc. Also we manipulated the output on the screens of the measurement equipment to show 'nonsens' and just an indication whether the measurement was done in the right way (kind of the "I'm not a robot" chapta like things we now have on the web). It also proved to be important to have highly trained personnel to do the measurements and a different team for evaluation.

In the audio(phile) world there are always big debates on comparing equipment, is the method right, A-B or A-B-X, is the music right, acoustic, amplified, modern classic etc. In the time I was still interested and building speakers I set up a test for a few friends with golden ears. Black acoustic transparent curtain (yeah discussion about that) and all the equipment behind that. Only one switch visible they could flip for A-B or A-B-X, whatever their preference. All they knew was they where comparing two pieces of equipment. Result as always, more discussion. Now there was one guy who only needed two flips of the switch to know, sat back and smiled: "You manipulated the recording". That was indeed the case. He explained he didn't listen to the music at all, he'd see it as noise and in his head scan this noise on a set of parameters and rate those. After listening to both pieces there was one parameter that didn't match and the way it did not was not natural. He repairs pro equipment in studio's.


Why all this?

Xbeeriments. What else?

Why is there almost never a very clear difference?
Why do big brewers use taste panels to evaluate their beers brew after brew instead of a gas chromatograph, analysing the same beer day after day?

It's not the palate (although there are people who don't have the genes to taste much).

Is it the way we evaluate, the lack of proper training on the right aspects?



Posted 34 days ago.

mchrispen
Bastrop, TX
485 Posts


Interesting post Ingoogni. We should chat - since I just got laid off from THX and went through many of the things you described above. Agreed, quality of the measurement is critical - however, I would submit there is a difference between getting something technically perfect (flat speaker performance across frequency, phase and amplitude, or perfect REC709 or P4 video representation) and having a viable product. I spent a lot of money and effort to have a properly calibrated plasma and high-end cinema audio system because I love movies so much. That said - I am also perfectly happy watching a movie or sports elsewhere, where the performance is not so good (looking at you modern cinemas!).

I think an analogy to say Budweiser or Coors works here. Both companies produce nearly perfect beer (by their standards and by mass consumption) over and over again. We home brewers seem to miss the fact that their manufacturing process is nearly perfect compared to ours. However, home brewers seem to prefer X, Y or Z vectors over a simple mass produced lager. I can say with confidence that Bud/Coors make continual improvements in their systems, and work intensely to minimize any impact on the final product. Like it or not - what they accomplish would make any other manufacturer pale in comparison (and I also worked in the CPU manufacturing world for a few years... ). So much of our collective brewing knowledge comes from the commercial world (often mistranslated or out of context) that we overweight (perhaps) it's authority. I am also shocked at how little we know about brewing from a pure chemistry and applied sciences perspective.

But to the point, XBMTs seem to struggle to isolate a statistically relevant result from a minor process change at the home-brew scale, but I think this will balance as more proposed topics are explored. If we took some of their hypothesis at a commercial scale, I am reasonably certain there will be a statistically relevant result more often. This seems to be the crux and point of Marshall's site - that we have far more flexibility and opportunity than someone brewing at 10 BBL or 10000 BBL scales. Yet, many home brewers - myself included - have shackled ourselves to dogmatic and inflexible procedures, just because someone said that is how it works period - not because they confirmed it personally.

An example, perhaps, of verifiable effects: DMS and diacetyl in beer. If you look statistically at people's sensitivity to such off flavors, they are all over the map. I am highly sensitive to DMS, but low sensitivity to diacetyl; not blind, but it has to be fairly high for me to detect. In both cases, there could be measurable PPM of each, but not every taster would notice or detect it, unless the level is high enough to make a perceptible difference overall in the beer. Expecting a gross pool of tasters (in this case usually BJCP, Craft Beer Fans and other beer drinkers) to always pick this out is just not possible. Oh and we cannot specifically test the testers, but could perhaps group testers based on say - BJCP rank, which is pretty unreliable as well. I took the tests at NHC last year and missed both. I had pretty high confidence on the BoPils test - but completely blew it. Marshall's recent analysis of the testers held this out to be more or less true.

I know of at least three Texas brewers that regularly test via both Tasting Panels and Gas Chromatography. The tasting panels are 'calibrated' buy tasting at least 2-3 times a week (triangle, but not completely blind), and usually tested against random spikes that should be regularly detected by specific testers (test the testers). GC provides fairly simple feedback, but much like using a spectrophotometer or accoustic waterfall plot - only means something against a standard reference. I am also amazed at the palettes of some of my brewer friends that can pick the most ridiculous things out. I always weight that feedback against the source. As for BJCP judging - it's pretty easy to tell when a judge is writing crap down to just fill space. 

I know that /u/testingapril has some issues with the way the algorithms are applied (p-values, etc.). I also often question the result that should be obvious (and I think is wrong). I don't know what else that Marshall's team can actually do to test that doesn't more directly imply a bias. Given the scope and scale and efforts - what they are bring to the table is pretty damned excellent. Short of setting up a trained tasting panel - (really difficult given the variety of beers and locations for testing), I think they have the best data they can collect.




Posted 34 days ago.

ingoogni
nl
314 Posts


A lot of people have no idea of the difference between liking something and the quality of something. What does giving three stars to an IPA mean? Bad IPA, brewing errors or I dont like the taste so it is not a good beer. Rembrandt was the best painter in the world ever. I don't like his paintings. Once people learn this difference they still have a problem in applying it concequently. Yet, final decisions are made by humans, at THX, at the printshop where I worked, at the brewery, often regardless of the measurement data. We rely on the senses of specialists, but when the average beerdrinker, brewer, beer judge comes in play the result is "average". Strange.

I started brewing in 1978, there was nothing. No decent literature so I had to invent it all by my self for some time. The XBMT's are not strange to me. This how I learned brewing. Later (~1984) I was lucky to have an old german brewmaster as guru. There I learned "making yeast", controlled fermentation, manipulating malt, mashing techniques. Making yeast and controlled fermentation where the biggest jump forward (although I blended every yeast in I could harvest from a bottle, no pure strains). After a long brewing pause came a big jump back. In hinsight this was caused by the use of too many specialty malts and by the use of the 'wrong' single strain yeasts (very personal opinion) I never bothered much with brewing communities, live or virtual, until recently and nothing I've seen there made impact on my brewing methods. They are stil the same as 30 years ago, even most of the equipment is.

The XBMT's are also well described in brewing literature and outcome is in cases the same (trub, reactivating yeast with oxygen, short boil) or different (fermentation temperature, mashing methods). So are the outcomes of my own experiments, temperature and yeast health and mass matter, the rest less. Boiling is overrated, no boilers are fine. Short boils are fine when you cool quikley. Fast cooling is important for colour and taste. Beer should be removed from yeast asap (or the other way around), for foam quality and stability. etc. I don't do triangle tests and I am very aware of my own bias.

As for literature, learn to read German, it's all there.

These examples above are just illustrations, there are many more. Just illustrations on where we depend on human senses of very skilled and trained people. In all these fields of work where the "average opinion" (don't know a better English expression) gets us no where. This one thing is what stands out for me in the XBMT's.

--
The company I worked for went belly up 5 years ago, still no other job but happily, albeit slowly, building my own brewery. And my audio, it's gathering dust :(




Posted 34 days ago.

uberg33k
Charter Member
The Internet
314 Posts


> As for literature, learn to read German, it's all there.

You know, you could start a blog a la Shut Up About Barclay Perkins with nothing but translations from old German and Dutch texts and never run out of things to write about.  That would be amazing.

I understand the issue as you're describing it, but what's the right answer?  Is there one?




Posted 34 days ago.

homebrewdad
Charter Member
Birmingham, AL
2480 Posts


That is a fantastic idea, uberg!  Ingoogni would be a rock star in the beer blogging world.



Posted 34 days ago.

ingoogni
nl
314 Posts


I prefer to listen to rock stars ;)

There is a lot of interesting modern stuff published by the Munich university.

There is an answer to the issue, a very simple one, an XBMT, what else. But a difficult one to perform. I'll have to talk to the Grolsch guys, but they are in heavy weather at the moment with the merger of the two big'uns that requires Grolsch et al to be sold.




Posted 34 days ago.

testingapril
Charter Member
Atlanta, GA
595 Posts


Would a simple solution be to administer a triangle test that virtually anyone could reproduce. Say dose a commercial beer like grolsch or sierra nevada with a precise amount of vinegar that is calibrated to average detectability levels and see if the triangle test can identify what should be identifiable?




Posted 34 days ago.

brulosopher
Charter Member
Fresno, CA
167 Posts


This is a genius fucking idea! I shot an email to Siebel asking about their sensory kit... haven't heard back.




Posted 34 days ago.

mchrispen
Bastrop, TX
485 Posts


What are you testing? That vinegar dosed beer tastes different than un-dosed? That the average person prefers sour beer over normal beer? What sample size?

Give us a robust hypothesis.

Seems easier to do the old Coke v Pepsi challenge and gather a million inputs.




Posted 34 days ago.

vinpaysdoc
Charter Member
High Point, NC
321 Posts


Bravo Dan




Posted 34 days ago.

testingapril
Charter Member
Atlanta, GA
595 Posts


Null hypothesis would be that a vinegar dosed beer does not taste different than a non dosed beer when dosed at "average threshold" levels.





Posted 34 days ago.

testingapril
Charter Member
Atlanta, GA
595 Posts


Marshall, BJCP uses the siebel kit and it's a crapload cheaper than buying from siebel. They've omitted vinegar from the kit to save money and because it's readily available at the grocery store.

Supposedly they were going to provide a flyer for how to do the home dosing for the grocery store sourced additives. I'm not sure the status of the flyer but I know it's been asked about on the BJCP Facebook page.

Null hypothesis would be that a vinegar dosed beer does not taste different than a non dosed beer when dosed at "average threshold" levels.



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Posted 34 days ago.

homebrewdad
Charter Member
Birmingham, AL
2480 Posts


That absolutely is genius.





Posted 34 days ago.

brulosopher
Charter Member
Fresno, CA
167 Posts


That's exactly the null. I have plans to do it with all sorts of off-flavors. Thanks for the BJCP tip, I'll shoot them an email!




Posted 34 days ago.

mchrispen
Bastrop, TX
485 Posts


Thanks for the BJCP tip

So they f***ed you too? 

From: brulosopher <listpost@brewunited.com>
Reply-To: brulosopher <listpost@brewunited.com>
Date: Wednesday, February 10, 2016 at 3:42 PM
To: Matthew Chrispen <mchrispen@gmail.com>
Subject: re: on tasting

Thanks for the BJCP tip




Posted 34 days ago.
Edited 34 days ago by mchrispen

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