Extending the Life of your Liquid Yeast

Second part of this.

I’ve already mentioned the benefits of liquid yeast. If you
tried one in your latest must, or better yet, did a comparison,
chances are that I’m be preaching to the choir. However, liquid
yeast is expensive compared to that little packet of dried
yeast. Sometimes it’s hard to justify an 800%+ price increase
just for yeast.

No fear, with a few tricks you can drop that price differential
down dramatically.

Pitch the Leavings

Do not do this with dry yeast!

Make a wine as per normal, except use liquid yeast. Right after
you rack the wine from the primary to the secondary pitch the
leavings in the carboy (don’t do this if you use plastic as the
primary) into the new wine. It’s better if you re-pitch just
after the kraeusen falls. The yeast will immediately start
munching on the new sugars. Voilà, two wines from one yeast.

Starters

Not so long ago Wyeast
Labs shipped their liquid yeasts in small packets. Wyeast at
the time recommended creating a starter. What Wyeast neglected
to mention was that if you could create one starter, you could
create two, and if you can create two, you can create four.

A starter is simply a liquid environment that liquid yeast can
use to propagate up to a level that is sufficient for
introduction into a 19 litre brew. Winemakers have it a little
easier to make starters then beer makers, but both are quite
simple.

Unlike agar which is a gelatinized medium for propagating
bacterial strains, a starter is liquid in nature. The liquid
should be as close to the brew as reasonable. The liquid yeast
pack is started as per normal and when it’s full the yeast is
introduced to the starter. The starter is sealed with an airlock
and let go. When the starter is at kraeusen (peak of yeast
activity/foam) it’s pitched into the must or wort.

The yeast multiplies in the starter dramatically before
the kraeusen, so you know that a) the yeast is healthy and
numerous, and b) it is in a stage of it’s growth where it eats
sugar ravenously. This is the ideal time to pitch into a fragile
must.

Making a starter for wine is simple . . . it’s known as grape
juice. Go buy some unsweetened grape juice, buy two litres. Get
two regular mouth litre (quart) mason jars (if you’re doing beer
starters, get lids and rings too). Get two #12 bungs from the
brew store. Take the jars to the brew store and test the
bungs on the jars. If you don’t have them, get two
air-locks for the bungs. Buy a liquid yeast of your choice
depending on your plans.

Start the yeast. Wait a day or so for the pack to expand.

Now, sanitize the jars. I use a tablespoon of bleach in the jars
+ water. At the same time, sanitize the bungs in the same
solution, also immerse a pair of scissors and the business end
of the yeast pack in the bleach solution. Leave them for an hour.

I boil a full kettle of water for about 10 minutes near the end
of the bleach sanitization. When the bleach is done, I dump
(re-use this solution!) the bleach and then rinse the jars by
filling them with boiling water. This gets rid of the bleach
residue which could inhibit the yeast and also provides a
secondary sanitization.

Pour the grape juice into the jars about 3/4 full. Cut the yeast
pack with the scissors and pour half of the yeast solution into
each jar. Bung and airlock.

Beer starters are a little more difficult. Instead of grape
juice, you need a cup of dried malt extract. Boil a couple of
litres of water and add the dried malt extract. Boil for ten
minutes. Pour the “wort” into the jars. Seal with mason lids and
rings and wait for them to seal (you’ll hear a pop as the air in
the jars compresses pulling down the lids. When they are cool
. . . or whenever you are ready (they are canned after all)
pitch the yeast. I do several of these at a time (like 8) so
that I have beer starters on demand.

If the yeast was active when you pitched it into the starter,
it’ll be about a day or so (for beer, longer with wine)
when one of the jars is ready to be pitched into your wort. Just
watch for the kraeusen, when you see it begin to settle, it’s
time to pitch.

You can let the second jar rest a long while, but I’ve never
gone more then a month. You have to start the yeast up again
in exactly the same way before pitching into another brew.

So now, if you pitch the leavings of each beer, you now have
made four brews just off of one liquid yeast pack. Now that’s
economy.

Now, all of this assumes that you’ve used careful and proper
methods of sanitization in all of your procedures. If you don’t
then you just might end up with a lot more vinegar then normal.

Now there’s an idea, malt and wine vinegar for X-mas. Not
hard to do either . . . .

Cheers,
lance