From: arf@ddsw1.mcs.com (Jack Schmidling)
Newsgroups: rec.crafts.brewing
Subject: Re: Wyeast and contamination (Re: esters, banana)
Date: 19 Aug 92 16:42:45 GMT
Organization: ddsw1.MCS.COM Contributor, Chicago, IL
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In article <binkley.714070889@beagle> binkley@boulder.Colorado.EDU (Jon Binkley) writes:
>>  = Jack Schmidling (arf@ddsw1.mcs.com)
>>> = Jeff Frane (gummitch@techbook.com)
>  
>>>Imprimis: no one ever contended that "Wyeast has never had a
>>>contaminated batch" -- but I in fact responded to your comment that
>>>"contrary to public opinion contaminated Wyeast supplies are not
>>>uncommon".  These, as anyone can see, are very different statements.  I
>>>asked you to please supply some data to substantiate your statement.
>  
>> Bad choice of words because "not uncommon" is rather flakey term.  However, I 
>> will direct you (in private), to a source that was the reason I selected the 
>> expression.  You can draw your own conclusion.
>
>Why keep such vital information private?  Keeping it anonymous is
>one thing, but why don't you post it with the caveat that it's secondhand,
>anonymous information?  

I dislike spreading rumors, particularly in a medium wherein it so so easy
to take things out of context or repeat the story inaccurately.  In this
case the individual is out of the country and the point was only mentioned
in passing via email and I am unable to clarify just exactly what he meant.

Furthermore, all attempts to email to Jeff have been bouncing lately, so I
will provide the info with the caveat that it came out in a casual conversation
and in itself is lacking in a very important detail.

An expert, well know and respected by most knowledgable brewers mentioned that
he had been tied up "the last few weeks with a disaaster casued by you know who yeast."  He indicated that there were a number of breweries around the country
involved in the disaster.

The quotes are to indicate the sense of what he said not the exact words and to
separate it from what I said.  The expression "you know who" was his and as
he did not say Wyeast, I was disinclined to publicly do so.

I really do not want to get in the middle of this.  What I said is all I know.

For more info, contact GF.

js

>>>Secundus: As Glenn Tinseth is pointing out, it's in fact very difficult
>>>to isolate the point of contamination, and blaming it on your yeast
>>>supply is the easy way out.
>
>> It is also just as easy to exonerate the yeast simply on reputation.  
>> Difficulty of isolating the contamination works both ways.
>
>As I've reported here before, I had one contaminated batch of beer
>using Wyeast and about fifty clean ones.  I can think of at least 8
>different possible sources of contamination for that one batch, all
>equally likely: 
>
>1) transfer of wort from kettle to primary fermenter
>2) something nasty in primary fermenter
>3) something nasty in yeast starter culture
>4) contaminated Wyeast
>5) transfer of beer from primary to secondary fermenter
>6) something nasty in secondary fermenter
>7) transfer of beer from secondary to botteling vessel
>8) addition of priming sugar to botteling vessel
>
>(Given the laxness with which I perform most of the above
>processes I'm amazed more of my beers are not contaminated!)
>
>Again, assuming these are all equally likely, the statement 
>"It was the Wyeast" has a 1/8 probablilty of being correct.
>The statement "It was not the Wyeast" has a 7/8 probability
>of being correct.  Yes, Jack, it could have been the Wyeast,
>but unless I heard of other people having problems with
>Wyeast English Ale yeast in July of 1991 I would conclude that
>it PROBABLY was not the Wyeast.
>
>Jon Binkley
>
Newsgroups: rec.crafts.brewing