October 4, 2017

How to choose the right yeast: strains

from <Yeast: the practical guide to beer fermentation(White and Zainasheff, 2010)>

when selecting a new yeast strain


  • attenuation
  • flavor profile
  • flocculation
  • reliability of supply
  • working temperature range

George Fix's division


  • ale: Clean/ Neutral/ Maltier/ Yeast/ Specialty
  • lager: dry/ crisp/ full/ malty

author's division


  • ale: clean, fruity, hybrid, phenolic, eccentric
  • lager: dry, full

each strains


  • idle temperature for most yeast=20'c
  • compounds(ester, fusel alcohols) of ale yeast: more(fruity, estery) less(clean)

clean ale strains


  • ferment slowly
  • flocculate at a medium rate
  • remain in suspension long enough to condition beer properly
  • sulfur under stressful condition
  • eg. california, american, scottish, english

fruity ale strains


  • ferment and flocculate very quickly
  • form large clump during flocculation->bright and clear beer 
  • more by-product eg. diacetyl
  • eg. british, irish, australian, belgian

hybrid ale strains


  • ale yeast fermented at cooler temperature than average ale yeast
  • clean, lagerlike beer eg. kolsch, altbier
  • ferment slower than fruity strains
  • flocculate at a medium 
  • remain in suspension long enough to attenuate and condition beer
  • sulfur(<lager)
  • eg. california common yeast

phenolic ale strains


  • attenuation high
  • flocculation low
  • historically, w/ bacteria=attenuation further, more characteristics
  • ensure vigorous ferment and complete before capping fermentor(avoid sulfur, diacetyl)
  • eg. german hefeweizen, belgian ale, trappist/abbey ale

eccentric ale strains


  • everything not clean, fruity, phenolic, hybrid
  • earthy, barnyard, sour
  • attenuate well
  • flocculation low
  • interesting flavor profiles(including phenol)

lager strains


  • stay in suspension longer>ale strains->remove most of the by-products
  • idle temperature=10~13'c
  • slower fermentation+cool temperatures=more sulfur&diacetyl
  • esters: ale>lager bc/ depends on membrane
  • drier, cleaner, crisp, refreshing(eg. american, scandinavian, german)
  • vs. clean, maltier, rounded, complex(eg. Munich helles, dunkel, and malty lagers)

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