SSSSHHHHH. THE YEAST IS ASLEEP!

SSSSHHHHH.  THE YEAST IS ASLEEP!

Devitera had a busy lead up to Christmas and we were at every event possible selling, selling, selling!  Christmas markets, outside shops, farmer’s markets, and of course our taphouse open afternoon (thank you to everyone who came along). 

Things were absolutely manic, and it gave me no time to brew beer.  So by January the 1st we were almost drunk dry.  I needed to urgently brew some more Power Fail Pale Ale, so were planning logistics just before Christmas with a view to brew first week back.  Various ingredients arrived via the post, and I collected the grain, which was still warm, fresh from Warminster. 

TEMPERATURES

A Rare Picture Of GlenAs a brewer I’m always thinking about temperatures.  Are things too hot, too cold, or just what temperature are they?  Various steps in the process are temperature sensitive.  For example when “mashing” (creating a porridge like substance with grain and hot water) I have to consider the temperature of the grain, room, vessel (called a mash tun), and the hot water.  1 degree makes a massive difference at this point!

The brew went smoothly and as I transferred the wort (a sugary substance for the yeast to eat creating beer), then pitched the yeast, I went home feeling content.  How wrong could I be!

WONDERFUL YEAST

Yeast is such a wonderful animal!  It is everywhere around us, and lives between -2 to 45 degrees.  It can live in aerobic (breathing oxygen) and anaerobic (without oxygen) environments, and each strain has its own behaviour.  Ales use one strain, whilst largers use another.  Bread is made from the same strain as Ale.

BACK TO THE BREW

The brewhouse was cold and the temperature of the fermentation vessel dropped over night (and the yeast went to sleep).  Now to give context this is a large vessel containing about 800 litres of soon-to-be beer.  Once the temperature gets too cold, below 18 degrees, the yeast starts to slowdown/go to sleep, and drops to the bottom of the vessel inactive.  As the yeast was just pitched it didn’t have time to establish itself, so this happened almost instantly. 

The challenge is how do you get such a large vessel warm again (ideally to 18+ degrees)?  The answer is of course heaters.  I have portable electric and gas heaters and direct them to the bottom of the vessel and wait (the hard bit).  About 6 hours later the temperature had risen, and fingers crossed the yeast was awake enough to multiply overnight.

Next morning I arrived to see the temperature had risen, which meant the yeast was active and multiplying.  This is the first stage of the fermentation process and lasts 24 hours.  Afterwards the next 3 days are spent eating the sugary “wort”.  This creates CO2 and alcohol!  On the 4th day you have beer!

BOTTLING, RACKING, & CONDITIONING

So yesterday we finally got to bottle and rack (put the beer into casks) the beer.  A hard day bottling by hand 1000 bottles.  Producing 6 casks, and 5 “bag in a box” beers.  We cleaned the brewhouse down, cleaned the fermenter of yeast, and made 40 boxes (cases) to move the bottles into.

Today I boxed the beer and moved it into my “warm room” where it will sit for 3 weeks (minimum) conditioning.  The room is kept around 19 degrees so that the yeast will be active and properly condition the beer.  This is a natural process and is similar to how you make champagne.  Only beers that are “bottle conditioned” will go through this process, and all other beers are “force carbonated” (injected with CO2).

FINALLY

So after a week’s effort, lost sleep (but not for the yeast), everything seems ok.  The beer is bottled and in casks, it’s conditioning, and it tastes great.  Now time to start selling :).

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