| Brewing is a magical process that turns the principle
ingredient - barley (fit only for feeding to animals in normal
circumstances!) - into a wonderful beverage called BEER.
Strictly speaking, 'ale' has no added hops, unlike 'beer' that
does. Flavour and bittering components are included to make the
final product more stable, interesting and enjoyable to drink.
That's brewing in a nutshell. For a bit more detail, read on. |
Beer ingredients |
The first step in the process is to turn the starch in the
barley grains into fermentable sugars. Moistened barley grains
are encouraged to produce small sprouts before being kilned
(heated) to stop them sprouting further. Luckily our maltsters
do this bit of the process for us and the malt arrives
ready crushed in 25kg bags on pallets. This is stored on
a mezzanine floor in the brewery ready for use. We also keep the hops up here in 5kg vacuum packs.
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Malt sacks |
| On the day before a brew all the ingredients are prepared.
First, the water is tested for calcium content and adjusted to
our requirements by the addition of dilute acid and gypsum based
dry treatment. Furthermore the water is now referred to as
liquor. Second, the malt (mainly pale malt) is weighed out with
the required amount of crystal malt (for
mouthfeel and flavour),
torrified wheat (for head retention) and roasted barley (for
colour and flavour). These dry ingredients are known as
the grist. Not surprisingly they are tipped into the
grist case. A different grist is used for each beer and
the stronger beers use more of it. |
Filling grist case
Grist case |
Other than freezing, the best way to preserve the freshness and
aromas of hops is to vacuum pack them. So, guess what? - we use
vacuum-packed hops that are weighed out into sacks ready for use
the following day. We use a blend of hops in our beers with a
different blend for each one - except Fuggle-Dee-Dum which is
100% Fuggles hops (though, even then, some come from Oregon and
some from Herefordshire!).
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Clean fermentation vessel |
The final jobs are to clean and
sterilise the fermentation vessel and the hot and
cold liquor tanks are filled and set to heat up/cool
down overnight.
Brew day! If all has gone well overnight we now have the two
liquor tanks at the required temperature, the grist case full of
the correct grist and a brewer (or two) with a vague idea of
what to do.
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Liquor tanks |
The grist is allowed out of the grist case under gravity and is
mixed with hot liquor in a mashing head on its way down into the
mash tun below where this porridge-like mixture (mash) sits on
its perforated false bottom. The temperature of the resultant
mash is controlled by mixing the hot and cold liquor in the
masher to achieve a temperature of 65 degrees centigrade.
Varying this temperature up or down by a degree or so alters the
proportion of unfermentable sugars (dextrins) and thus the
sweetness and mouthfeel of the finished beer. The mash is
left for an hour during which time the enzymes in the malt are
activated and convert most of the starch contained in the malt
into fermentable sugar.
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Mash tun |
| The liquid wort (as it has now called) contained in the mash tun
is drained off through the perforated false bottom and
pumped into the copper. This takes about an hour during which
time the remaining sugars are rinsed out by spraying the mash
with hot liquor, a process known as
sparging. |
Inside the copper |
| When sparging is
complete the remaining solids are removed from the mash tun via
a small door on the side and put into sacks. There is much
competition among brewery staff to perform this task. Not. The sacks of
spent malt are taken away by a local farmer. |
Emptying the mash tun |
As soon as the wort covers the stainless steel heating coil in
the bottom of the copper, the gas-fired heater is switched on
and starts to heat the wort. It reaches a vigorous
rolling boil
some two hours later.
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| As soon as the wort boils a charge of hops (known as
copper
hops) is added to the copper via a
manway on top. These
add bitterness to the finished beer. After 55 minutes boil,
during which time the bitterness is extracted from the hops and
the wort sterilised, a second charge (late hops) are added for
the last 5 minutes of the boil and give the finished beer aroma
and hoppiness. |
Adding hops to the copper |
| The copper heating is turned off after the 1 hour boil and the
hops settle on to the perforated false bottom (yes, another one)
within. The hopped wort is then recirculated through the hop bed
until it is seen to be bright in the sight glass.
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Sight glass |
| It is then ready to be cooled and this
is achieved by running it through a
heat exchanger containing stainless steel
plates. Cold water circulates across one side of the plates and
the hopped wort on the other. This has the effect of cooling the
wort and heating the cold water. |
Heat exchanger |
| The cooled wort is pumped into the
sterilised fermenting vessel (prepared earlier) and
the hot water is pumped into the brewing liquor tank ready to be
adjusted for the following day's brew. |
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| When empty the copper is opened and the
spent hops raked out
into a wheelbarrow and composted as a mulch/soil conditioner. At
the end of the brewing day all the equipment is washed down
ready for use the next day. |
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| The next requirement for this magical process is yeast. We use a
fresh charge of dried yeast for each brew and this is added to
the fermentation vessel as it fills at around 20 degrees
centigrade. Shortly after the yeast is added to the hopped wort
it starts to convert the sugar that we extracted from
the malt into alcohol and CO2. The following morning
there is a thick head on the fermenting beer forming a
protective coating as it ferments. The CO2 is exhausted to atmosphere but the
alcohol - which seems to be what people like in their beer -
stays put and we carefully monitor its level (ABV - alcohol by
volume), until it reaches the desired level. This is achieved by
cooling the beer, which slows the process right down. The whole
process takes 5 or 6 days until the finished beer is ready to be
racked into the casks. |
Fermentation vessel |
| On the day before racking, the beer is
pumped from the fermentation vessel over to the racking
tank where it is left overnight for some of the
remaining yeast to drop out of suspension. A small
amount of yeast is carried over into each cask to allow
the beer to ferment inside it. The CO2 created in this
secondary fermentation puts a sparkle or
condition into
the beer - and makes it 'cask conditioned'. |
Washing the casks |
| The following morning the beer is
run into the casks (which have been sterilised earlier
on our cask washing machine) through the
racking cock. This fills the casks from the bottom preventing air
being mixed with the beer, which would ruin it.
Finings are
added at this point to enable the beer to drop bright at the pub
by settling out the remaining yeast. |
Beer is racked off into casks |
| There is a saying that "beer should be godly. It should spend at least one Sunday in the fermenter" - ours do, you'll be glad to hear. After racking the beer then goes into the cold store where it stays for a minimum of one week at 12 degrees centigrade to allow conditioning to take place before its onward journey to our customers. |
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