WET AND WONDERFUL, LIQUID YEAST
Each of these yeasts comes in a foil packet
inside which is a separate smaller packet containing the yeast starter
solution, in other words a small amount of malt extract. This
inner packet is surrounded by the liquid yeast. Four or five days before you
are ready to brew, follow the directions on the packet, you press the foil
pack to break and release the starter solution into the liquid yeast. You then leave
the packet lying flat in a warmish place for one to three days. In that
time, the yeast will start to multiply in the malt extract solution just as
it would in a real wort.
The carbon dioxide it gives off makes the packet swell and that’s when you
know the yeast is ready for the next stage. You can use it just as it is,
pitching it into your wort just as you would do
with a dried yeast but you are best to go through
another stage first.
Because there isn’t enough yeast in the packet at
that stage to start off a full fermentation
quickly
enough to be safe,
the best thing to do is culture it up until there is. That’s easy enough.
You must make up a starter solution by adding a dessertspoonful of malt
extract to 250ml of water, bringing it to the boil then cooling it rapidly
down to 28C. This is easily done by immersing the pot in which you boiled
the solution in cold water, making sure you don’t get any of the water into
your solution.
Now take a cleaned and carefully sanitized 750ml
bottle and pour the starter solution into that. Next you must cut the yeast
packet open and pour its contents into the bottle, taking care not to allow
contact with unclean surfaces. Stop the bottle either with a rubber cork and
airlock (sanitized of course), or some cotton wool, give the whole thing a
good shake then leave it somewhere warm to go to work. In two or three days (even less if the yeast is
fresh), there should be strong signs of activity and the yeast is ready to
be pitched into your fermenter.
The normal temperature for ale ranges from 16 to
24 degrees C. A few strains ferment well down to 13 degrees C but 20 degrees
C is about average. Lager strains normally work between 0 to 16 degrees C
but performs best from 10 to 12 degree C for primary fermentation with a
slow reduction to 0 degrees C during secondary
fermentation. Fluctuations in temperature such as cooling and warming from
day to night can adversely affect yeast performance. Each yeast strain
ferments different sugars to varying degrees, resulting in higher or lower
final gravities which will affect the residual sweetness and body. Some
yeasts are also better than others at setting out
and leaving the beer
clear.
WYEAST—Yeast
Profiles
ALES
(Saccharomycess cervisiae)
1007.
Our original Ale Yeast of German origin Ferments dry and crisp leaving a
complex yet mild flavour. Produces an extremely
rocky head and ferments well down to 55*(12*C). Flocculation is high and
apparent attenuation is 73 to 77% Optimum
fermentation temperature: 62*F (17*C)
1028.
British #2 (London
Ale, previously British Ale) Rich minerally
profile, bold woody slight diaccetyl production.
Medium flocculation. Apparent
attenuation 73 to 77%. Optimum fermentation temperature: 68*F (20*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
to 77% Optimum
fermentation temperature: 68*F (20*C)
1084.
First considered just
British, but now more specifically Irish. Slight residual
diaetcyl is great for stouts. It is clean
smooth, soft and full bodied. Medium flocculation and
apparent attenuation 71 to 75%. Optimum fermentation temperature:
68*F (20*C)
1098.
British Ale Yeast from Whitbread. Ferments dry and crisp, slight tart and
well balanced.
Ferments well down to 55*F
(12*C) Medium flocculation, apparent attenuation 73 to 75%
Optimum fermentation temperature: 70*F
(21*C)
1214.
Belgian Ale. Abbey-style top fermenting yeast suitable
for high gravity beers doubles, triples and barley wines.
High flocculant strain,
which clears well. Apparent attenuation 71 to
75%.
1338.
European yeast from Wissenschaftliche in Munich.
Full-bodied complex strain finishes very malty.
Produces dense rocky head during fermentation.
High flocculation, apparent attenuation 67 to 71%.
Optimum fermentation temperature: 70*F (21*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 and light. Medium flocculation.
Apparent attenuation 71 to 75%. Optimum
fermentation temperature: 52*F (17*C)
2035.
American Lager Yeast. Unlike American pilsner styles, it’s bold, complex and
woody.
Produces slight
diacetyl. Medium flocculation, Optimum
fermentation temperature: 50*F (17*C).
2042.
Danish Yeast Strain.
Rich, yet crisp and dry.
Soft, light profile, which accentuates hop characteristics.
Flocculation is low, apparent attenuation is 73 to 77%. Optimum fermentation
temperature: 48*F (9*C).
2112.
California Lager
Yeast. Warm fermenting bottom cropping strain, ferments well to 62*F
while
keeping lager characteristics, Malty profile,
highly flocculant, clears brilliantly.
Apparent
attenuation 72 to76%.
2124.
Bohemian Lager Yeast.
Ferments clean and malty,
rich residual maltiness in high gravity
pilsners,
Medium flocculation, apparent attenuation 69 to 73%.Optimum fermentation
temperature: 48*F (9*C).
2206.
Bavarian Lager Yeast Strain used by German breweries. Rich
flavour, full bodied, malty
and clean. Medium flocculation, apparent attenuation 73 to 77% Optimum fermentation
temperature: 48*F (9*C).
2308.
Munich Yeast from Wissenschaftliche in Munich.
One of the
first pure yeasts available to American home brewers.
Sometimes unstable, but smooth soft well rounded and full bodied. Medium
flocculation, apparent attenuation 73 to 77%
Optimum
fermentation temperature: 50*F (10*C)
This is a list of only a few of the liquid yeast strains available from
WYEAST
For a more detailed list….
Home
Brewing Yeast Strain Guide
Choosing which Yeast to Use…..
Home Brewing Style
Guidelines
RE-USING
LIQUID YEAST
There are many ways to reuse yeast, some brewers
use techniques involving slants & microscopes, which theoretically would
allow reusing the yeast infinitely. The method I have used successfully is
to remove half a litre of vigorously fermenting
wort two to three days into the fermentation,(there
is lots of fresh yeast in it) into a plastic 1.25litre soft drink bottle.
Seal & allow to sit at room temperature for a few hours
then transfer to the fridge.
When you want to reuse the yeast, remove from the
fridge a couple of days before intended use and
allow to sit a room temperature for 12 hours. Check to see if fermentation
has commenced (pressure in the bottle). If not, add a solution of one
tablespoon of malt extract or sugar mixed in some boiling water and then
allowed to cool. Pour this into the bottle a shake vigorously & ensure
strong fermentation has commenced before making your next brew.
I have reused yeast which has been stored up to 3
months, but a few weeks are probably safer. With each generation, more risk
of infection or problems with yeast are likely to
occur so this is why a figure of 4 to 5 times is generally quoted as a
maximum of reusing yeast unless laboratory techniques are used.
Many people like to make a number of cultures
from the packet or from the first brew