Where Does Yeast Come From?

[Lilo]

Had a few people over for a session and a run down of the Brewery the other day. All went well until someone asked me.

"Where does yeast come from and how do they get different strains".

Only answer I could give was "Ross's.. and it depends on what bag you select" Bugga me I do not know.


Could one of the more educated on the forum give me a run down and save a little humiliation next time.

Cheers

 

[Lilo]

Very Clever use of Google, wish I'd a thought of that. Of course you could google the answer to many of the queries posted in this forum.. that too would be clever...

Thought a discussion here would be nice. Thought that was the point of a discussion board.

Guess I got that wrong as well... Bugga... Sorry for annoying you. I'll go bury myself in Google then... Cheerio...

 

[NickB]

I would have thought this to be a very legitimate topic for discussion here. I find it a little harsh that someone reasonably new to brewing can com here asking quite genuine questions, and basically get told to F**K off and google it. As Lilo states, yes he could do that, however I don't know about you, but I value the opinions of the people on this board much more highly than some random and possibly very old web site.

Now, fair enough if the question had been "why is my airlock not bubbling", "where can I buy some hops", "where do I put the kitten", as these are very frequently posted topics, however this particular topic is not one I've seen up for discussion here, and while I'm nowhere near the longest serving member on this forum, I have been around a number of years, and have read many interesting and informative topics.

So, in summary (before I write a thesis on the subject), I would love to know a genuine answer to the topic at hand, and think this would make a very informative thread topic (unlike some of the bullshit on here of late).

Cheers & Beers

 

[winkle]

I'd assume that brewing yeast originally derived from the wild yeasts that resided on the grains exterior, the varieties coming from natural selection in differing breweries conditions and, eventually, deliberate human selection to engineer specific strains.

 

[wabster]

I recall an article I saw once, could have been a Peter Jackson Beer Hunter episode, where he said or implied that some of the traditional Czech Republic brewers originally used wild yeasts which then colonised their breweries. After that point they brewed in open vats and the wild yeasts now at home there, did their work.

I guess over time the sciences of brewing and microbiology were used to isolate the yeast that were best in terms of results, and then innoculate future brews with it in a more closed environment.

Seems to make sense for me, though the origins of the "wild yeasts" could be open to speculation. After all bread making has been done for ages and that uses yeasts too.

Cheerz Wabster

 

[sunburnt]

It poses the question did we domesticate yeast or did they do it themselves?

You could argue both cases; firstly that previous brewers selected past batches based on the success of the brew and therefore were naturally selecting better yeast.

I also guess you could argue that yeast naturally adapted to the conditions of the wort and fermenting conditions, which is why a wheat beer strain is very different to a larger strain.

Interesting question!

 

[Jazzafish]

Until recently, yeast wasn't understood. Keep in mind that yeast was not included in the german purity law, and fermentation was a bit of a mystery. Some brewerys made better beer, as did different regions. As science progressed, and the microscope invented it was discovered that yeast was the mystery behind fermentation. When this was discovered, yeast was included in the purity law. It was also discovered that there are many varieties of yeast that have their own characteristics and influences on the beer.

Nowdays, we can isolate and select different strains of yeast to suit the desired beer we wish to make.

The cool thing is that there will be more strains out there to be found for us to make new flavours.

 

[Nick JD]

Son, when a Mommy yeast and a Daddy yeast love each other very much...

I heard the vikings (probably an old wive's tale) used to have a "magic village beer stick". It was passed around to anyone who needed to innoculate their sweet barley sugar juice and turn it into beer.

The wood of the stick must have been soaked with a desirable yeast strain, but it'd require them to give subsequent stirs during fermentation. After a few hundred generations some natural selection must have happened when the brewers who brewed crap beer were rejected from using the stick.

Maybe.

Wild yeasts selectively bred. Like wolves turned into great danes and chihuahuas.

 

[Screwtop]

I heard the vikings (probably an old wive's tale) used to have a "magic village beer stick". It was passed around to anyone who needed to innoculate their sweet barley sugar juice and turn it into beer.

I imagine that stick sat around in the air between uses..........(clue) or maybe Helga used to ride it around pretending it was a horsie :lol:

Screwy

 

[MHB]

It goes further back than that, beer and bread are why we became civilised, the introduction of both is older than metal.
Both bread and beer need yeast, it wasnt until Louis Pasteur that we began to understand and select for specific strains.
MHB

 

[Yeastie Beastie]

Yeasts are single-celled fungi. As fungi, they are related to the other fungi that people are more familiar with. These include edible mushrooms available at the supermarket, common bakers yeast used to leaven bread, molds that ripen blue cheese and the molds that produce antibiotics for medical and veterinary use. Many consider edible yeast and fungi to be as natural as fruits and vegetables.

Over 600 different species of yeast are known and they are widely distributed in nature. They are found in association with other microorganisms as part of the normal inhabitants of soil, vegetation, marine and other aqueous environments. Some yeast species are also natural inhabitants of man and animals. While some species are highly specialized and found only in certain habitats at certain times of the year, other species are generalists and can be isolated from many different sources.

Bakers yeast is used to leaven bread throughout the world and it is the type of yeast that people are most familiar with. Bakers yeast is produced from the genus and species of yeast called Saccharomyces cerevisiae. The scientific name of the genus of bakers yeast, Saccharomyces, refers to saccharo meaning sugar and myces meaning fungus. The species name, cerevisiae, is derived from the name Ceres, the Roman goddess of agriculture. Bakers yeast products are made from strains of this yeast selected for their special qualities relating to the needs of the baking industry.

The typical yeast cell is approximately equal in size to a human red blood cell and is spherical to ellipsoidal in shape. Because of its small size, it takes about 30 billion yeast cells to make up to one gram of compressed bakers yeast. Yeast reproduce vegetatively by budding, a process during which a new bud grows from the side of the existing cell wall. This bud eventually breaks away from the mother cell to form a separate daughter cell. Each yeast cell, on average, undergoes this budding process 12 to 15 times before it is no longer capable of reproducing. During commercial production, yeast is grown under carefully controlled conditions on a sugar containing media typically composed of beet and cane molasses. Under ideal growth conditions a yeast cell reproduces every two to three hours.

In a nutshell it is commercially grown in different enviroments to produce the exact same strain of yeast every time.

 

[pdilley]

Until Pasteur everyone thought the oxygen/air did the fermentation through chemical reaction with the wort and if you thought otherwise you were ostracised quite the same as on the modern AHB forums. The environment was quite the same even back then amongst brewers. Everyone didn't know exactly the whys of how things happened and of course if you succeeded in making good beer you kept repeating the same thing again and again and it became dogma and your way was right and anyone with a different way had to be wrong.

Of course malting was done by the brewer and not by any special company as it was an easy enough process to do. Management of the malting was a simple process of making little piles of grain and shifting little piles into bigger piles to regulate temperature and the biggest issue of the day was not mice eating the grain but the cats. They would use the grain piles as their litter and crap and piss in the malting grain. Crap could be removed but cat piss really could skunk flavour a resulting brew :blink:

All brewing is derived from natural yeasts or moulds (in the case of fermented foods and Sake) growing on the grain as we know from today -- it just takes water and a little warmth to activate them. Everything in the eyes of the brewers of then was colourful and creative as an explanation until Pasteur when the greater collective agreed that it was the yeast that caused the fermentation and the rest is history.

Cheers,
Brewer Pete

 

[Yeastie Beastie]

or maybe Helga used to ride it around pretending it was a horsie :lol:

Screwy

"Giddie Up Helga, we need that stick nice and ready for a brew day coming up"

 

[jayandcath]

Very Clever use of Google, wish I'd a thought of that. Of course you could google the answer to many of the queries posted in this forum.. that too would be clever...

Thought a discussion here would be nice. Thought that was the point of a discussion board.

Guess I got that wrong as well... Bugga... Sorry for annoying you. I'll go bury myself in Google then... Cheerio...

Lilo, I totally agree. Of late there just doesn't seem to be the same willingness to help or guide the lessor knowledgable of the brewing fraternity, or the answers that you do get are simply "this is how you do it stupid" or my favorite "did you use the search function??". I have been part of this forum for a few years now and have made some great friendships and learned a lot about the subject of beer and brewing, but I have definately seen a drop in the quality and helpfulness of answers. And considering were all here for the same reason.......BEER! its giving me the shits.
So sometimes you might think that a question has been done a thousand times or that its beneath you, I would just ask you to remember that you too had to start somewhere and someone helped you!!! so show a little tolerance and try and show people how to use the site not just blow them off.

Now, if have just read the above comments and sighed under your breath that I'm a knob, I ask you to lean back on your chair and give yourself an uppercut because your the dickhead that I'm talking about.

Oh and Merry Christmas
Jay

 

[Bribie G]

In old English breweries yeast wasn't even called yeast, it was called 'barm' and was a bit of a mystery - along with Phlogiston which we all know is responsible for heat and fire, and the Luminiferous Aether which of course accounts for light transmission (and even the first crude radio transmissions). Pasteur put them right but we could have done without the Pasteurisation of bottled beer. Thanks for nothing frog boy. B)

 

[geoff_tewierik]

For those that haven't got it yet, there's an article in the latest Beer & Brewer, issue #11, about yeast, worth a quick read IMO.

And yes the "stick" method is mentioned, as is most of the other stuff mentioned in this thread.

Only read the article this morning over a cuppa, funny that it's been asked about here on AHB - co-inky-dink?

 

[Screwtop]

your the dickhead that I'm talking about.

Oh and Merry Christmas
Jay

Just googled dickhead...................and ................well, **** you!

Merry Christmas to you too :lol:

 

[Lilo]

Thanks all for the replies. Some very informative stuff. I will of course "Google" as well to compliment what has been talked about here.

 

[Lilo]

Just googled dickhead...................and ................well, **** you!

Merry Christmas to you too :lol:

I did as well and it turns out I know a few..

Happy New Years

 

[dr K]

Stolen direct from pils

Lets have a look at this yeast.

Certainly by 1842 brewers and scientists knew that yeast was an important part of beer making (quite an advance from the days of The Reinheitsgebot where yeast is not even mentioned) though they were uncertain as to its function.

The renowned chemist of the time Justus von Liebig believed that fermentation was a chemical reaction triggered by the death and decomposition of yeast, whereas Theodore Schwann considered that fermentation was a living process involving the reproduction of yeast cells. It was not until Pasteur's experiments at the end of the 1870's that Schwann was shown to be correct.

The brewers did know that different breweries' yeast affected beer in different ways. In fact Sedlmayer and Dreher (more on them later) travelled around Europe and Britain around 1830 carrying a specially commissioned metal tube with a hidden valve with which they "stole" samples of fermenting wort, yeast and all.

The most probable answer to all this is that brewing practices in Northern Europe, particularly the British Isles, where the yeast was skimmed from the top of the ferment contrasted with the southern German practice which involved fermenting and lagering at low temperatures(beer was not made in the summer).

Thus we have two strains of yeast, one adapted to live well in warm, open conditions and another adapted to cold conditions, where the yeast would sink to the bottom during the storage period.

Fermentation, after all, occurs throughout the wort, not exclusively at the top or bottom !
The yeast used in Bavaria at the time was probably a mixed strain of S,Cerevisiae and S.Carlsbergensis (now S. Uvaram). S.Uvarum was first isolated as a single cell by Emil Hansen at the Carlsberg Brewery in Denmark in 1883.

The Carlsberg Brewery was founded by Jacob Jacobsen in 1847. Jacobsen had studied under Sedlmayer and it is believed that his yeast came from Sedlmayer's Spaten Brewery in Munich.

Pasteur was pretty pissed off by the Prussians so decided one way to screw what would become Germany was to beat that at their own game..brewing beer, he was successful in his isolation but unsuccessful in creating a French dominance of brewing.
You can see how old the article is,nearly ten years old actually in those days the LHBS in my area stocked "Franklin" malt and "English Lager Malt" but, apparently, no Czech or even German Pilsener.

K