From: djc@ece.cmu.edu (David Collins)
Subject: Re: what's the difference? (Wyeast)
Organization: Carnegie Mellon University
	<1993Jan26.150217.18645@rosevax.rosemount.com>
Date: Thu, 28 Jan 1993 19:13:12 GMT


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Date:    Mon, 7 Oct 1991 22:58:02 -0400 (EDT)
From: D_KRUS@UNHH.UNH.EDU (Daniel L. Krus)
Subject: Yeast and Spec. Grav's.

There's been a few questions lately about yeast and characteristics associated
with them.  Here is a retype of some information I received from Wyeast
relative to their yeast.  This information was obtained a while ago and
supposedly this was to be updated and expanded.  If anyone has the latest
update I would appreciate a copy of it from you since Wyeast wasn't too
tickled that I contacted them directly.  Sorry if there are any typos.

YEAST CHARACTERISTICS

   Some yeast strains are more active and vigorous than others.  Lager strains
   in particular do not show as much activity on the surface as many of the
   Ale strains.  We provide an adequate quantity of yeast to complete fermen-
   tation with varying amounts of lag time depending on strain, freshness,
   handling, and temperature.  If you find it too slow, make a starter as
   recommended on the package.  In any event, a closed fermenter with an
   airlock is recommended.

TEMPERATURE

   The slow onset of visible signs of fermentation can be improved by starting
   fermentation at 75 deg. F (24 deg. C) until activity is evident, then
   moving to your desired fermentation temperature.  A few degrees does make
   a significant difference without adversely affecting flavor.

   The normal temperature for Ale yeast range from 60-75 deg. F (16-24 deg. C)
   A few strains ferment well down to 55 deg. F (13 deg. C).  68 deg. F (20
   deg. C) is a good average.  Lager strains normally ferment from 32-75 deg.
   F (0-24 deg. C).  50-55 deg. F (10-12 deg. C) is customary for primary
   fermentation.  A slow steady reduction to 32 deg. F (0 deg. C) during
   secondary fermentation typically works well.

   The fermentation rate is directly related to temperature.  The lower the
   temperature, the slower fermentation commences.  Fluctuations in tempera-
   ture such as cooling and warming from night to day can adversely affect
   yeast performance.

ATTENUATION

   Apparent attenuation of yeast normally ranges from 67-77%.  The attenuation
   is determined by the composition of the wort or juice and the yeast strain
   used.  Each yeast strain ferments different sugars to varying degrees,
   resulting in higher or lower final gravities.  This will affect the resid-
   ual sweetness and body.

FLOCCULATION

   All brewing yeast flocculate.  The degree and type of flocculation varies
   for different yeast.  Some strains clump into very lary flocculate.  Some
   floc very little into a more granular consistency.  Most yeast strains
   clump and flocculate to a moderate degree.

pH RANGES

   Typical pH range for yeast fermentations begins at about 5.1 and optimally
   4.8.  During the course of fermentation the pH reduces to typically 3.9-
   4.1 and as low as 3.1 in some wines.

ALCOHOL TOLERANCES

   The alcohol tolerance for most brewing yeast is as least to 8%.  Barley
   wines to 12% can be produced by most Ale strains.  Pitching rates need to
   be increased proportionally to higher gravities.  Alternately, Champagne
   and Wine yeast can be used for high gravities sometimes reaching alcohols
   to 18%.

YEAST PROFILES

   Ales  (Saccharomyces cerevisiae)

      1007.  Our original Ale Yeast of German origin.  Ferments dry and crisp
      leaving a complex yet mild flavor.  Produces an extremely rocky head and
      ferments well down to 55 deg. F (12 deg. C).  Flocculation is high and
      apparent attenuation is 73-77%.  Optimum fermentation temperature:
      62 deg. F (17 deg. C).

      1028.  British #2 (London Ale previously British Ale).  Rich minerally
      profile, bold woody slight diacetyl production.  Medium flocculation.
      Apparent attenuation 73-77%.  Optimum fermentation temperature:  68 deg.
      F (20 deg. C).

      1056.  American Ale Yeast.  Ferments dry, finishes soft, smooth and
      clean, and is very well balanced.  Flocculation is low to medium.
      Apparent attenuation 73-77%.  Optimum fermentation temperature:  68 deg.
      F (20 deg. C).

      1084.  First considered just British, but now more specifically Irish.
      Slight residual diacetyl is great for stouts.  It is clean smooth, soft
      and full bodied.  Medium flocculation and apparent attenuation of
      71-75%.  Optimum fermentation temperature:  68 deg. F (20 deg. C).

      1098.  British Ale Yeast from Whitbread.  Ferments dry and crisp,
      slightly tart and well balanced.  Ferments well down to 55 deg. F (12
      deg. C).  Medium flocculation, apparent attenuation 73-75%.  Optimum
      fermentation temperature:  70 deg. F (21 deg. C).

      1338.  European yeast from Wissenschaftliche in Munich.  A full bodied
      complex strain finishes very malty.  Produces a dense rocky head during
      fermentation.  High flocculation, apparent attenuation 67-71%.  Optimum
      fermentation temperature:  70 deg. F (21 deg. C).

   Lager  (Saccharomyces uvarum)

      2007.  Our original Lager Yeast Strain.  Specific for pilsner style
      beers.  Known as many things, we call it Pilsen.  Ferments dry, crisp,
      clean and light.  Medium flocculation.  Apparent attenuation from
      71-75%.  Optimum fermentation temperature:  52 deg. F (11 deg. C).

      2035.  American Lager Yeast.  Unlike American pilsner styles.  It is
      bold, complex and woody.  Produces slight diacetyl.  Medium floccu-
      lation, apparent attenuation 73-77%.  Optimum fermentation temperature:
      50 deg. F (10 deg. C).

      2042.  Danish Yeast Strain.  Rich, yet crisp and dry.  Soft, light
      profile which accentuates hop characteristics.  Flocculation is low,
      apparent attenuation is 73-77%.  Optimum fermentation temperature:  48
      deg. F (9 deg. C).

      2124.  Bohemian Lager Yeast.  The traditional sazz yeast from Czechoslo-
      vakia.  Ferments clean and malty, rich residual maltiness in high
      gravity pilsners, medium flocculation, apperent attenuation 69-73%.
      Optimum fermentation temperature:  48 deg. F (9 deg. C).

      2206.  Bavarian Yeast Strain used by many German breweries.  Rich flavor,
      full bodied, malty and clean.  Medium flocculation, apparent attenuation
      73-77%.  Optimum fermentation temperature:  48 deg. F (9 deg. C).

      2308.  Munich Yeast from Wissenschaftliche in Munich #308.  One of the
      first pure yeast available to American homebrewers.  Sometimes unstable,
      but smooth soft well rounded and full bodied.  Medium flocculation,
      apparent attenuation 73-77%.  Optimum fermentation temperature:  50 deg.
      F (10 deg. C).

   Saccharomyces delbrueckii, S. cerevisac

      3056.   Bavarian Weissen.  A 50/50 blend of S. cerevisiae and
      Delbrueckii to produce a south German style wheat beer with cloying
      sweetness when the beer is fresh.  Medium flocculation, apparent
      attenuation 73-77%.  Optimum fermentation temperature:  56 deg. F (13
      deg. C).

   Wine Yeast

      3021.  Prise de mousse, Institute Pasteur champagne yeast race bayanus.
      Crisp and dry, ideal for sparkling and still red, white and fruit wines.
      Also can be used for Barley wines.  Optimum fermentation temperature:
      58 deg. F (14 deg. C).

      3028.  French wine yeast ideally suited for red and white wines which
      mature rapidly.  Enhances the fruity characteristics of most wines.
      Optimum fermentation temperature:  72 deg. F (22 deg. C).

   Malo-lactic Bacteria

   Leuconostoc oenos

   4007.  Malo-lactic culture blend isolated from western Oregon wineries.
   Includes strains Ey2d and Er1a.  Excellent for high acid wines and low pH.
   Softens wines by converting harsh malic acid to milder lactic acid.  Can be
   added to juice any time after the onset of yeast fermentation when sulfur
   dioxide is less than 15 ppm.
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--
 Dave Collins					Carnegie Mellon University
						Pittsburgh, Pennsylvania
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 "It's such a fine line between being clever and being stupid."  Spinal Tap