As described in the previous section,
grain contains a fair amount of starchy elements. These elements
can not be fermented by yeast yet, but need be transformed into a
fermentable sugar. This transformation will be done by enzymes (amylase),
which are formed once the grain starts to germinate.
This process is called malting.
Note: I always buy the malt I use direct from a homebrew shop. If find the
process of malting too time consuming and I therefore leave it up to the
specialized malting firms.
MALTING PROCESS IN A NUTSHELL
1. Select
First, you need to select raw barley that
is suitable for brewing. A professional maltster measures the amount of
protein in the grain, looks for suitable moisture content, etc. You, on the
other hand, can only gauge the quality of the grain by look and feel. Look
for large plump kernels of 2-row barley. You also want the kernels to be of
fairly consistent size to encourage a consistent germination rate later.
2. Soak
Soak the Barley in water. You want the
water content of the barley to get up to about 45%. This means that if
you're malting 10 pounds of barley, you want it to weigh just over 14 pounds
when you're done. The soaking process will take you a minimum of 40 hours,
or at least two days. Historically, quality malts were soaked 65-72 hours
[1]. During this time you need to change the water at least daily, and
preferably every 8 to 12 hours. You could also devise system whereby the
water is constantly but slowly drained while being replenished by some type
of slow sprayer. Nineteenth century maltsters changed the water every 24
hours, but current practice is to sprinkle fresh water over the grain
constantly---which also allows the soaking time to be reduced to the 40-45
hour range.
3. Germinate
After your barley is soaked, you need to
germinate it. The traditional floor malting method should work fairly well
for you. To do this, spread your soaked barley on a clean floor to a depth
of about 8 inches. The temperature in your germinating room should remain
consistent at about 60 degrees F. It will take about 8 to 15 days for the
barley to germinate. During this time, you will need to turn and move the
barley about every 12 to 24 hours. You should also spray a light mist over
it to keep it moist, though not wet. Note that the time the barley takes to
germinate properly can vary widely. Less than 8 days is possible, though
sometimes as much as 24 days may be required.[1]
Examine the barley to see when germination
is complete. You want to look for the new growth stemming out from the end
of the kernels and up the back of the grain. This growth is called the "acrospire".
When the acrospire is roughly the same length as the kernel, the malt is
fully modified. If you let it grow longer than the kernel size, the malt is
said to be "over modified". If it is shorter than the kernel size, the malt
is "under modified".
Neither under nor over modified malt is
desired. Undermodified malt still has starch in the grain that could be
converted to sugar. Overmodified malt has already started consuming the
sugars during the normal plant growth cycle.
4. Kilning
When the malt is fully modified, you need
to "kiln" it. This is a 2-step process: drying and curing. In the first
step, you are drying the malt at a low heat over a long period of time to
drive off the moisture. This is typically done at 90 to 100 degrees F with
constant air movement, and takes about 2 days. The grain is done drying when
the moisture content drops into the 4 to 5% range.
In the curing stage of kilning, the
temperature is raised to 172 to 220 degrees F for another day and half to 2
days (in the 1880s, the preferred temperature was 172, in the 20th century,
the practice changed to use 180-220 F).
If you are producing lighter colored pale
ale malts, your malt is now ready. However, if you want darker colored
malts, you would increase the temperature during the curing stage to produce
what are called "high kilned malts".
Some malt varieties would require some
changes in the schedule. For a black patent malt, you would roast the malt
in a revolving drum at over 400 degrees for one to two hours. For an amber
malt, you would increase the temperature during the last 14 hours of drying
time to about 140-150 degrees. To make a crystal malt, you would take the
germinated barley and heat it to 150-170 degrees for 2 hours with no
ventilation, and then increase the temperature to about 250 degrees F. [1,2]
A more smokey flavour from peated malt
The peated malt gives an authentic subtle
smoky flavor to the alcohol.
Peated malt is a malt with the smoky
smell that comes from treating barley with peat, in other words, dry the wet
malt over a peat fire so the wet malt absorbs some of the smokey
flavors of the burning peat.
Peat is nothing more than compressed,
decayed vegetable matter cut from peat bogs and used as fuel. The pungent
smoke it gives off when burnt is used in the malting of barley intended for
certain Scottish malt whiskies, especially on Islay.
In general, the professionals are
drying the "green malt" over a peat fired kiln. For a lightly peated whisky,
malt is dried for six hours with peat, then a further 24 hours with hot air.
If you like a more stronger smokey flavor, dry the malt entirely over
a peat fire for 48 hours.
If you want to buy peated malt from a
homebrew shop, it is in most cases called "Rauchmalt", the German term for
smoked malt. In most cases, you can by it in three different
strengths:
- low (5 ppm phenol),
- medium(10 ppm phenol),
- high(15 ppm phenol)
How strong should the smokey flavor be?
In the professional industry, the level of
peat is measured in "ppm of phenol". For us, this does not
clarify anything. The only thing we can do is measure the known level of
phenol in commercial available whiskeys. I have searched the web and
contacted several distilleries about the levels of phenol in their whiskeys.
To my surprise I have found different levels of phenols in some cases, which
makes it a bit confusing.
| Distillery |
Country/Region |
Content
range of ppm phenol |
|
High (Heavy peated) 30 -
50 ppm |
| Laphroaig
10 Yr. Old |
West
Islay
malt |
40 - 50 |
| Ardbeg |
West isles |
52 |
| Lagavulin |
West Isles |
40 - 50 |
| Bruichladdich
Octomore
|
Islay
malt |
40 |
| Talisker
10 Yr. Old |
Island
malt |
25 |
| |
|
|
|
Medium 10 - 20 ppm |
| Bowmore |
Islay
Malt |
20 |
| Glenkinchie
10 Yr. Old |
Lowland
Malt |
|
| Glenfiddich |
Speyside
Malt |
|
| Highland
Park |
|
5-15 |
| The
Famous Grouse |
Blend |
|
| Johnnie
Walker Red Label |
Blend |
|
| Cutty
Sark |
Blend |
|
| Bruichladdich
Port Charlotte |
Islay
malt |
10 |
| |
|
|
|
Low ( slightly) 1 - 5 ppm |
| Glenmorangie |
Scotland
Highland Malt |
2 - 3 |
| Aberlour |
Speyside
Malt |
2 |
| Glenfarclas |
|
2 |
| Cragganmore |
|
2 |
| Deanston |
|
none |
| Glengoyne |
|
none |
| Bushmills
Malt 10 Yr. Old |
Ireland |
none |
| Connemara
Peated Malt |
Ireland |
none |
| Tyrconnel
Single Malt |
Ireland |
none |
| Jack
Daniels Single Barrel |
Bourbon |
|
| Jim
Beam |
Bourbon |
|
| The MacTarnahan |
|
3 |
A hassle free guide for peating your malt, it is
definite worth to try..
Replacing a portion of the regular malt by
peated malt will enhance the flavor of the alcohol tremendously. I would
recommend to give it a try, as it is not as complicated as it sounds.
A very hassle free method of peating goes
like this:-
Soak 1,000 grams of malted barley
in water, until it weighs approx .1,300 grams .
Take this grain and place it on a
tight-mesh screen, like metal window screen, and then put another layer
of screen over the top of the grain, to prevent ash from falling onto
the grain, which would cause a creosote like flavor in the malt.
Start a small fire under the screen
with a bit of peat from the garden store.
Dry the malt over the fire slowly to
prevent the malt from browning/charring- misting the fire and the grain
with a water spritzer helps.
stop when the grain is back down
to weighing 1,000 grams.
Mix it 50/50 with some unpeated regular
unpeated 2-row malt, and brew an all-grain malt batch.
Mash and ferment the malt as you would
normally do.
The Process
Grain content,
Malting, Grinding, Mashing,
Filtering,
Fermenting,
Distilling, Ageing.
