Technical Topic: What’s a Malt Analysis Sheet and What’s It Good For?
Beer Defect: Tannins
Style Topic: BJCP Category 4 - Dark Lagers
Thomas Barnes, 1/5/2011
Technical Topic: What’s an Analysis Sheet and What’s It Good For?
What’s an Analysis Sheet?: A malt analysis sheet (sometimes
called a malt spec sheet) is a document which describes the “vital
statistics” of each type, or each lot, of malt. Since slight variations
between different batches of malt can greatly affect malt character,
professional brewers, and all-grain homebrewers striving for consistency
from batch to batch, rely on malt analysis sheets when formulating
There are two types of Analysis Sheets, Typical Malt Analysis and
Lot Analysis. Typical Malt Analysis represents the maltster’s best estimate
of the brewing properties of a particular variety of malt based on the
current year’s barley crop. Typical Malt Analysis figures are readily
available on any maltster’s web site and are useful when sourcing new
varieties of malt or designing new recipes. Understanding the terminology
in a Typical Malt Analysis is helpful if you wish to details about a particular
malt’s color, diastatic power, potential extract yield and suitability for use
with a particular mashing regime.
Lot Analysis describes the brewing properties of a particular batch
of malt. Even with modern levels of quality control, different lots of malt
can have noticeably different lot analyses, which can affect the character
of your brew! For this reason, if you’re trying to “dial in” a recipe so that it’s
consistent from batch to batch, you must reformulate your recipe slightly
every time you brew. Paying careful attention to differences between
different lots of malt helps you do this.
Getting Malt Analysis Sheets: Homebrewers don’t always have
easy access to malt analysis sheets, especially lot analysis sheets, since
they typically buy malt from a homebrew supply store rather than directly
from the maltsters. If you are buying malt by the bag, better homebrew
suppliers will typically supply you with a lot analysis, which they get (or
should get) from the maltsters. If they do not, some manufacturers or
suppliers have web pages where you can look up the lot analysis for your
particular batch of malt.
If you are buying your grain by the pound from a homebrew
store, the store might have a lot analysis on file which you can look at,
although this usually isn’t the case. Usually, the best they can offer
you is a typical malt analysis for that particular malt. If the malt is sold
out of large bags, however, you might be able to get the lot number off
the bag and get a lot analysis directly from the maltster.
The lot number should be printed on each bag. If you’re lucky
you can find the lot analysis on the maltster’s web site. If you’re not so
lucky, you might need to telephone, email or fax them.
Reading a Malt Analysis Sheet: At minimum, an analysis
sheet should provide information about color, extract potential,
mealiness (friability or vitreosity), moisture percentage, protein
percentage (total and soluble) and size assortment of the malt. For
base malts, the analysis should also include diastatic power. Tests
and measurements are standardized by the ASBC (American Society
of Brewing Chemists) or the EBC (European Brewers Convention), but
exact information provided will vary from company to company.
Specialty malts typically won’t have complete analysis sheets,
especially for traits such as diastatic power. A typical malt analysis
sheet might look much like Figure 1.
Reading the top columns from right to left, the abbreviations are:
Barley Type: Two-row or six-row barley will be specified.
Practically, this sort of information is limited use compared to other
aspect of the analysis sheet.
Barley Variety: Certain types of barley are traditionally
preferred for certain types of beer and different strains of barley impart
different flavors and aromas to beer. Strains such as Optic and Maris
Otter are typically used for English ales, while strains such as
Harrington are associated with certain types of American ale. While
it’s not likely to be mentioned on the analysis sheet, the location where
Fig. 1. Typical Malt Analysis Sheet
Brewers Malt
Colored Malt
Data taken from:
Protein Max.
Extract Dry
the barley is grown can also play a role in its flavor and aroma. Just as
with grapes and hops, terroir matters for barley as well!
Assortment: This is a measurement of the average size of each
kernel of malt, as determined by the percentages of kernels which fall
through a sieve with openings of a certain size. Practically, malt size gives
you an idea of malt quality as well as the gap needed on your malt mill in
order to get a proper crush.
In ASBC testing, the listings for size indicate numbers mean the
percentage of kernels which remain on a screen with 5/64 -in., 6/64 -in.,
or 7/64 -in. mesh and will be expressed in terms of “5/64 Max”. The EBC
test is similar, except that a 2.2 mm mesh is used. In some cases, though,
the size might just be listed as the percentage which is “plump” or “thin.”
The term “Thru Max” is the maximum number of kernels which fall through
the screen.
As a rule of thumb, 6-row malt and more highly modified malts will
also be a bit smaller, while 2-row malt will be a bit plumper. Typically, the
plumper the kernels, the better the extract yield. Malt with more than 1%
thin kernels (those which fall through a 5/64-in opening) or 2% less than
2.2 mm is likely to be undermodified or otherwise unsuitable for brewing.
Equally important is uniformity of kernel size, since a large variation
means a less uniform grain crush. Higher size variation between kernels
can mean lower quality malt, although this isn’t usually a problem with
modern malts. Regardless of plumpness, a lot of malt must have at least
90% adjacent sizes in order to crush reasonably well (i.e., about 90%
must have be left on the 6/64 -in., and 7/64 -in. screens).
H2O % Max: This row indicates the moisture percentage within the
malt. It is also sometimes expressed as “Moisture content,” “% m.c.” or
just MC. Moisture content on the malt is very important since, not only is it
an indicator of quality, it also helps determine extract yield and storage
stability of your malt. The lower the moisture content the better. Malt can
have a moisture content of as low as 1.5% MC. Malts with higher moisture
content are more prone to mold growth and lose more aroma and flavor
during storage. No malt should have moisture content above 6% and
colored malts shouldn’t have moisture content above 4% (except for
caramel/crystal malts where 3.5-6% moisture content is acceptable although lower moisture is still better). British ale malts have the lowest
moisture content, followed by Munich, Vienna, Pilsner, and lager malts.
Caramel malts trap more water during drying, so they have slightly higher
moisture content than other specialty malts. Malts with an excessively
high level of moisture are said to be “slack” and are likely to have been
poorly stored, dried or kilned.
Moisture content also affects extract yield, since each percentage
increase of moisture content results in an identical drop in potential
extract yield. You can’t turn water into sugar!
Color ASBC Deg. Lov.: This column indicates the malt’s color.
Malt color is sometimes expressed as “degrees SRM,” “degrees
Lovibond” or “degrees EBC” or just “°SRM,” “°L,” or “°EBC.”
Not only is color a likely indicator of how a malt is likely to smell and
taste in your beer, but it’s an indicator of how dark your beer is likely to
be. While exact malt color isn’t so important for dark beers, it’s critical if
you wish to make very light colored beers, such as Light Lagers or
The color of a particular type of malt can vary widely from
manufacturer to manufacturer and lot to lot. It’s particularly important to
pay attention to malt color if you are switching between different brands of
malt, since each maltings has its own color range. Differences in color are
more pronounced at the dark end of the color range, with dark malts from
the same maltings varying by up to 40° L from batch to batch!
The color of U.S. and Canadian malts is expressed in terms of
Standard Research Method (SRM) values or in degrees Lovibond. The
color of European malts is usually measured in European Brewing
Convention (EBC) units.
A rough conversion between the different units:
Degrees Lovibond = Degrees SRM
Degrees EBC = (degrees L x 2.65) - 1.2
Degrees Lovibond = (Degrees EBC + 1.2)/2.65
Protein Max: This column is a measure of how much protein or
nitrogen is in the malt and how much of that material can be dissolved
in water. It indicates the maximum percentage of protein (or nitrogen)
by weight.
Protein percentage depends a great deal on the type of barley
used to make the malt, but it can also be an indicator of its degree of
modification and diastatic power. Indirectly, protein percentage can
also be used to measure nitrogen percentage at a rate of 1% Nitrogen
per 6.25% Protein.
Highly diastatic American 6-row malts have the highest protein
percentages (up to 13%), while European malts have slightly lower
protein content (8-10%). North American malts are traditionally a bit
higher in protein than their European equivalents.
Malts with total protein values greater than 12% (1.9% Total
Nitrogen) are more vulnerable to mash runoff and problems, protein
haze and storage instability, unless adjuncts are used to reduce the
total protein percentage of the grist. Likewise, when adjunct grains or
sugars are used, malts of at least 10% protein are required to get
appropriate levels of Free Amino Nitrogen (FAN) for yeast nutrition
and to achieve proper head and body for all but the thinnest of beers.
“Sol.” indicates the percentage of soluble proteins by weight. It
is sometimes expressed as “Soluble protein” or “% SP.” Alternately,
there might be a line for “Total Soluble Nitrogen,” or “% TSN,” instead,
which indicates the total percentage of all soluble nitrogen in the malt.
Regardless of the calculation uses, the soluble protein or total soluble
nitrogen percentages are used to calculate the soluble nitrogen ratio.
“Total” indicates total protein percentage by weight and can
also be expressed as “Protein %” In some cases, the analysis sheet
might also give a “total nitrogen” or “TN” percentage, or substitute that
figure for the total protein percentage. Where total nitrogen is given, it
indicates the percentage, by weight, or all nitrogenous matter in the
malt, not just proteins.
“S/T” [Soluble/Total] indicates the ratio of soluble protein to total
protein as a percentage. This figure can also be described as “Soluble
Nitrogen Ratio,” or “% SNR. Where Soluble Nitrogen and Total
Nitrogen figures are given, Soluble Nitrogen/Total Nitrogen, SN/TN or
Kolbach Index is listed instead.
In all cases, this ratio is calculated by dividing soluble protein (or
nitrogen) value by the percentage of total protein (or nitrogen) to get a
ratio between the two.
The soluble protein (or nitrogen) ratio is an important indicator of
malt modification; the higher the number, the greater the degree of
modification. Malts destined for infusion mashing, such as English
pale malt should have an SNR of 36-42%, up to 45% for light-bodied
beers. Beer made using just malt with 45% or higher SNR, will have a
thinner body and poorer head due to lack of soluble nitrogen. For
traditional lager malts, 30-33% indicates undermodification, while 3740% indicates overmodification.
For a lot of malt with SNR than usual, the brewer must adapt by
adding or modifying protein rests during mashing. Likewise, when
dealing with a lot of malt with a lower than normal SNR, the brewer must
shorten or eliminate protein rests.
Extract Dry Min.: This column lists the minimum potential extract
yield, as a percentage, at 0% moisture content. It is sometimes listed as
Extract Yield.
Even for homebrewers who don’t particularly care about
consistency from batch to batch, Extract Yield percentages are of
interest since it is an indicator of brewhouse efficiency - how much sugar
you can wring out of your mash - which directly relates to wort gravity
and the finished beer’s ABV.
FG: This line indicates minimum extract yield, as a percentage. It is
obtained by grinding a sample of malt into flour (0.2 mm average particle
diameter), mashing the powder under laboratory conditions and then
determining the amount of soluble materials (sugars, dextrins, starches
and proteins) extracted. Since it is just a measure of maximum extract
yield, the test ignores problems associated with a very fine grain crush,
such as tannin extraction and mash runoff problems.
FG is usually read side by side with the CG column. Taken on its
own, it can be seen as an indicator of malt quality. The higher the extract
percentage, the better the malt.
More typically, FG is expressed as DBFG, also described as
%DBFG or FGDB. This is an acronym meaning “Extract Yield - Dry
Basis, Fine Grind.” A higher %DBFG indicates a malt with less protein
and husk material and more soluble sugars and starches which can be
extracted during mashing. Base malts should yield a minimum of 78%
CG: This line indicates minimum extract yield, as a percentage,
using a coarser grain crush (0.7 mm average particle diameter), which is
more like that obtained in brewery operations.
More typically, CG is expressed as DBCG, %DBCG or CGDB. This
is an acronym meaning “Extract Yield - Dry Basis, Coarse Grind.” It is
used in conjunction with %DBFG to determine the degree of starch
modification the grain experienced during the malting process. Unlike
DBFG, the malt is crushed in a way which simulates a typical brewhouse
malt crush, although actual brewhouse efficiency figures will be 5-15%
lower than DBCG percentages.
Even though CG figures are likely to be closer to actual brewhouse
extract yields, they are still higher than “real world” yields. As a rule of
thumb, actual brewhouse efficiency figures will be 5-15% lower. This is
because, the malt has all its moisture removed before crushing begins,
laboratory mashing equipment is more efficient than brewhouse mash
tuns and the laboratory mash attempts to extract as much material as
possible, ignoring potential problems with tannin extraction.
The coarse-grind results are intended to demonstrate to the brewer
the maximum that can be achieved using a crush that approximates that
used by most breweries.
F/C Diff. Max: This is a measurement of the maximum difference
between Fine Grind and Coarse Grind extract yields, listed as a
percentage and obtained by subtracting the coarse grind percentage from
the fine grind percentage. It can also be expressed as just F/C or FG/CG.
The difference between FG and CG percentages is another
indicator of malt modification. An undermodified "steely," “glassy” or
vitreous malt, which requires a protein rest, has a FG/CG difference of
1.8-2.2%. Well-modified, “mealy” malt suitable for infusion mashing will
have a FG/CG difference of 0.5-1.0%.
D.P. Min.: A measurement of Minimum Diastatic Power, sometimes
just expressed as DP. North American maltings measure diastatic power
in degrees Lintner. The terms IOB or .25 maltose equivalent are also
sometimes used and are equivalent to degrees Lintner. European
Other Ways of Measuring Extract Yield
Malt suppliers can measure potential extract yields in a
variety of ways other than FG/CG ratios.
AICG: Also described as “CG, As Is,” this is an acronym
meaning “As Is, Coarse Grind.” It is a measurement of coarse grind
extract yield performed on malt with the listed moisture content,
rather than malt where the moisture has been removed first. It gives
more realistic, lower, estimates of extract yield. In other respects, it
is identical to DBCG.
AIFG: Also described as “FG, As Is,” this is an acronym
meaning “As Is, Fine Grind.” It is almost identical to DBFG, but uses
malt with the listed moisture content, rather than malt where the
moisture has been removed first.
Hot Water Extract (HWE): This is a measurement of extract
yield used by British maltsters. It is a measure of how many liters of
wort at S.G. 1.001 a kilogram of a malt will give at 68 °F (20 °C). It
can also be listed as hot water extract, or L°/kg at 7M (malt ground
to particles an average of 0.7 mm in diameter - a coarse grind) or
L°/kg at 2M (malt ground to an average particle size of 0.2 mm in
diameter - a fine grind). Divide by 386 to get DBCG or DBFG,
respectively, expressed as a decimal. HWE for two-row lager or
pale shouldn't be less than 300 at 2M, 295 at 7M.
Cold Water Extract (CWE): This is a measurement of malt
modification sometime used by British maltsters. It measures the
amount of extract that is soluble in cold water. CWE percentage of
19-23% indicates a malt suitable for infusion mashing.
DLFU: This is a measurement of FG/CG used by continental
maltsters. It is identical to that measurement.
Hartong (VZ 45°): This is a measurement of FG/CG
sometimes used by continental maltsters. It is similar to CWE, but
the water is held at a higher temperature (113°F/45° C) to allow for
some enzyme action. The range of values is approximately double
that of CWE.
maltsters measure diastatic power in terms of °WK (Windisch-Kolbach
DP °Lintner = (°WK + 16) / 3.5
DP °WK = (°Lintner x 3.5) -16
DP is a measurement of the malt’s ability to convert starch into
fermentable sugars. Malts with a DP of 25-30 °Lintner will just convert
their own starches, while those with higher values can convert excess
starch into sugars, making them suitable for making beers which use
adjunct grains.
DP values range from 25-30 °Lintner for Munich, Vienna or
lightly toasted malts, to 35-40 for English pale malt, ~100 for pale
lager malt up to 125+ for “hot” American 6-row pale malt. Toasted,
roasted or kilned malts have no diastatic power, so DP usually isn’t
listed for them.
Viscosity Max.: This is a measure of the breakdown of betaglucans during malting. It is often expressed as cP (centipoises units)
or sometimes IOB. Malt with a high laboratory wort viscosity (over
1.75 CP) will need a beta-glucan rest to get the wort to run off easily
during sparging. If viscosity is measured in IOB units, it should range
between 6.3-6.8 at 158 °F [70 °C].
Other Malt Sheet Figures and Terms
1,000-Kernel Weight or Bushel Weight: The weight of a fixed
volume of malt. This is an old measurement which gives a rough
estimate of the plumpness or thinness of the malt kernels, as well as
Using the Numbers
Once you have obtained the numbers from your malt lot
analysis, you can use them to adjust or design your recipe.
AICG = DBCG/(1 + Moisture Content) - 0.002
Adjusted yield = AICG/brewhouse efficiency.
Where brewhouse efficiency is expressed as a decimal instead of a
Once you know brewhouse yield, you can predict the likely starting
gravity (in SG or °Plato) per pound of malt in a gallon of water:
SG per 1 lb. malt in 1 lb. water = Adjusted yield x 46.214
°Plato per 1 lb. malt in 1 lb. water = Adjusted yield x 11.486
Working backwards, you can determine brewhouse efficiency using
the following formula:
Brewhouse efficiency = ((SG x gal. of wort)/46.214)) /
((DBCG/(1 + moisture content) - 0.002) x lb. of malt
Brewhouse efficiency = ((°P x gal. of wort)/11.486)) /
((DBCG/(1 + moisture content) - 0.002) x lb. of malt
moisture content. An acceptable range for 1,000-kernel weight is 36-45 g,
while 42-44 lbs. is acceptable for bushel weight.
Alpha-Amylase or Dextrinizing Units (DU): Also sometimes
described as Alpha Amylase Minimum. This measurement is similar to
DP, but describes the malt’s ability to produce alpha amylase (which
breaks down dextrins). Lager malts will have 35-50 DU, English pale malt
has around 25 DU, while Munich/Vienna malt might have 10 or fewer DU.
Conversion Time (minutes): Sometimes given instead of, or in
addition to, diastatic power. European base malts should start to convert
starches to sugars in less than 10 minutes, American base malts should
start converting within 5 minutes.
Degree of Clarity: Another estimate, based on ASBC standards, of
the clarity of wort the malt will produce. "Normal" to "slightly hazy" are
acceptable values.
Degree of Crystallization: This measurement is only used for
specialty malts which are supposed to have a vitreous texture, such as
crystal malt. Caramel malts should have a degree of crystallization above
85%, while crystal malts should have a score of 95% or higher.
DMS precursor (DMS-P): This is a measure of the levels of Smethyl methionine (SMM) and dimethyl sulfoxide (DMSO) in the malt,
which are converted to dimethyl sulfide (DMS) when the wort is heated.
These compounds are generally present in higher quantities (5-15 ppm) in
continental lager malts, less for ale malts. The greater the degree of
modification, the lower the DMS-P levels.
Friability: This is a measure of the malt’s likelihood of crumbling
when crushed. It is similar to mealiness and is sometimes substituted for
that test. Any malt should be at least 80% friable, while those used for
infusion mashing should be at least 85% friable.
Growth: Also described as Acrospire Growth. This is another
traditional method of assessing the degree to which malt has been
modified. Acrospire growth is expressed in ranges 0-1/4, 1/4-1/2, 1/2-3/4,
3/4-full, or overgrown (measured in length of acrospires to length of the
barley kernel). The longer the acrospires, the more modified the malt.
American maltsters typically let the acrospire grow to ¾ length, while the
acrospires is allowed to grow ¾ to the entire length of the kernel for
English pale malts. By contrast, traditional German lager malts only
allowed the acrospire grow to ½ to ¾ the length of the kernel.
Mealiness (%): The texture of a malt kernel’s endosperm can
be described as “mealy” “"half-glassy/glassy-ends" (AKA “hard ends”)
or "glassy" (AKA “vitreous” or “steely”) depending on degree of
modification during mashing. Mealiness measures the percentage of
kernels in a sample which are classified as mealy (i.e., no more than
25% of the endosperm is “glassy”). Kernels are “half-glassy”/”glassy
ends” if the endosperm is 25-75% glassy. Kernels where the
endosperm is over 75% glassy are described as being “glassy,”
“vitreous,” or “steely.”
Mealiness is another measure of malt conversion and is also a
useful measurement of how well the malt will crush. Since mealy
endosperm is more permeable by water, it is also more accessible to
starch conversion enzymes, so mealiness is an indirect indicator of
extract yield.
A higher degree of modification during malting results in more
mealy malt kernels. Less modified malts have more a steelier texture
and give less extract. Any base malt should be at least 90% mealy,
while malts intended for infusion mashing must be at least 95% mealy.
Where mealiness/half-glassy/glassy is expressed as a ratio, the
percentage should be at least 92%/7%/1% for decoction or step
mashing, and 95%/4%/1% or better for infusion mashing.
Odor of Mash: This is a one or two word description of how the
mash smells, based on ASBC standards. Often there will be no listing,
or a listing of “normal.” “Aro” or “aromatic” indicates a greater than
normal aroma while “V. Aro” or “very aromatic” means a much higher
than normal aroma. Other descriptors include “bread," “crackers” and
“burnt coffee.”
Speed of Filtration: An estimate, based on ASBC standards, of
the levels of beta-glucans in the malt, as well as the degree of starch
and protein conversion. It can be used as an estimate of the speed of
runoff during sparging.
Vitreosity: This is the opposite of mealiness. It is a
measurement of the average level of “glassiness” of the endosperms
in a sample of malt kernels. It is measured by taking a set number of
malt grains, slicing them open and examining the endosperm. A score
of 1 is assigned to kernels with glassy endosperms; 0.5 to half-glassy
kernels; 0.25 to those with glassy ends; and 0 to mealy kernels. The
sum is totaled and averaged, with a vitreosity of 0-0.25 preferred.
Due to the unreliability of this test (it depends on subjective
observations of vitreosity) it is seldom listed.
Beer Defect: Tannins
Description: Tannins refer to a broad class of polyphenols
which have molecular weights of 500-3,000. They are naturally
present in many plant materials, such as tea, coffee, peat moss, tree
fruits and grapes (in the skins, pits and seeds), oak, hops and barley.
When oxidized, they impart a harsh bitterness, drying mouthfeel and
reddish color to beer. In certain cases, tannins can combine with high
molecular weight proteins to form chill (protein) haze.
The German term for tannin astringency is “Herbstoffe” and
astringency or tannin character is considered to be a defect in German
style beers. A feature of German dark lagers is the use of dehusked
dark malt to get dark grain colors and flavors without imparting husky
notes. Dehusked dark malt also gives beers such as Baltic Porter and
“India Dark Ale”/Black IPA their distinctive malt character.
In barley kernels, tannins are found mostly in the husk, but also
exist in the pericarp and the aleurone layer. Tannins are also present
in hops. In a typical wort, 2/3 of tannins present are from the malt,
while the other third come from hops.
While tannins help precipitate both hot break and cold break,
excessive levels, especially excessive levels of malt-derived tannins have
unwanted effects on appearance, flavor and mouthfeel.
How Are Tannins Perceived?: Polyphenols are detectable in
aroma, flavor and mouthfeel, and might also alter a beer’s appearance.
Appearance: Tannins can impart a reddish color to beer (seen in
beers such as Flanders red ale). In some cases, they can interact with
proteins naturally found in the malt to cause chill (protein) haze.
Aroma and Flavor: Variously described as harshly bitter, husky,
oaky or tea-like. In some cases, their flavor is described as vinous,
reminiscent of red wine or unripe fruit, metallic, chalky or dusty. They
typically impart a harsh, lingering, unpleasant bitterness, as compared to
mellower, less lingering, more pleasant hop bitterness imparted by alpha
Due to the comparatively large size of most polyphenols molecules,
they aren’t particularly volatile and are easier to detect in flavor than
Also, keep in mind that flavor and mouthfeel effects play off of each
other. Aspects of polyphenolic “flavor” are actually elements of mouthfeel.
Mouthfeel: In beer tasting, mouthfeel is used to describe the
physical characteristics of the beer as it interacts with the tissues of your
mouth, such as viscosity, carbonation, and so forth. Polyphenols truly
affect mouthfeel because they’re astringents - they chemically react with
proteins and extract water from tissues. For this reason, tannins are used
to tan hides for leather. So, when polyphenols contact your taste buds,
tongue or inside of your mouth, they actually start to “tan your hide” from
the inside out! You perceive this sensation as a drying, puckering or
astringent sensation, or occasionally as a dusty texture in the mouth.
When Are Tannins/Astringency appropriate? Low levels of
tannins are acceptable, even expected, in wood-aged beers, including
styles such as Flanders Red Ale. For most styles of beer, however,
tannins are inappropriate.
Origins of Tannins in Beer
Excessive levels of tannins can get into your beer due to bad
technique at virtually each step of the brewing process.
Grain Crush: An excessively fine grind, or a high proportion of flour
from your crush, aids in extracting polyphenols from husks. Also, very fine
particles of husk material can be run off with the wort where they can
release even more tannins during the wort boil. This is one of the most
common causes of astringency.
Cures: Crush your grain properly. Make sure that the grain husks
are mostly intact rather than being shredded or ground to flour. An ideal
grain crush will leave the husks virtually intact while pulverizing the
material inside the husk.
Mashing/Steeping: Tannins can be extracted from malt husks
during malting or steeping. Bad process during this step is also a big
source of astringency.
The three ways that tannins can get into your beer during
mashing/steeping are:
1) Strike water, steeping, or mashing out temperature too high.
Above about 170 °F, tannins are extracted from grain husks.
2) Excessively long mashing times. Very long contact with water
can extract tannins from husks.
3) Improper wort pH: Tannins are slightly acidic, so alkaline mash
conditions help to extract tannins.
Cures: Keep strike water and mash temperature during mash out
below 170 °F. Keep mash pH within proper ranges (5.2-5.6 pH). Treat
mash water to avoid excessive alkalinity. Add dark/specialty grains
towards the end of mashing in order to minimize tannin extraction, since
they don’t need to undergo starch conversion.
Sparging: Excessive sparging and sparging with hot and/or
alkaline water can also extract tannins from grain husks. Bits of husk
can also be carried into the wort during runoff and sparging.
Cures: Keep sparge water between 5.2 and 5.6 pH and below
170 °F. Stop sparging once the SG of the runoff falls to about 1.010.
Recirculate or filter your runoff until it runs clear.
Wort Boil: Tannins are extracted from plant materials during
boiling, but paradoxically, a good wort boil also helps to solve hazing
and instability issues associated with polyphenols, since they bind with
proteins to form the hot break and cold break. High levels of hops,
especially bittering hops boiled for long periods of time, can also
impart unwanted polyphenols.
Partial grain brewers can often get polyphenols in their beer
during wort boil if they steep specialty grains in their wort kettle.
Brewers who add huge quantities of hops to their brew can also impart
unwanted polyphenols.
Cures: Don’t let any material which might impart unwanted
levels of polyphenols into your wort: grain husks, whole fruits,
excessive levels of hops.
If you steep your grains in your wort kettle, use a grain bag so
that you get all of your grains out of the kettle before you start boiling.
Never let your steeping grains get above 169 °F. Don’t steep your
grains for prolonged periods (more than 45 minutes or so).
Use smaller amounts of high alpha hops for bittering rather than
larger quantities of low-alpha hops.
Get a vigorous rolling boil of at least 1 hour to aid hot break
formation, but limit total boil time to no more than two hours after
you’ve added your hops (you get maximum alpha acid extraction after
2 hours). Use kettle finings (e.g., Irish moss) to promote hot break.
Wort Cooling and Fermentation: Polyphenols can cause chill
haze and astringency if cold break or trub is carried into the cooled
wort. The scummy brown material which appears on the top of
fermenting wort, and the trub which falls out of solution, also contains
a high concentration of polyphenols. If you are not careful, it can get
into the finished beer.
Cure: Filter or whirlpool wort to leave most of the hot and cold
break behind (but you’ll want to let a bit into your beer to aid yeast
development). Use blow off fermentation along with adequate head
space, to help get trub out of your beer - it should end up in the blowoff container or on the sides of your container rather than in your beer.
When you rack your beer, be careful to disturb the sediment as little
as possible. Try to get as little trub as possible when you rack.
Conditioning/Dry Hopping: Excessive hop levels or excessive
dry hopping times can extract polyphenols from the hops. During
conditioning, polyphenols levels can be reduced by fining, cold
conditioning or aging. To a much lesser extent, leaving your beer on
the trub for extended periods of time can also allow polyphenols to get
into your beer.
Cures: Don’t let your beer sit on the lees in primary for long
periods of time (i.e., more than a month or so). Limit dry hopping time.
Use a hop bag or equivalent to help get hop material out of the beer. If
necessary, fill your bag with marbles to get it to sink. You can sanitize
both the bag and the marbles before you add it to your beer. If your
beer suffers from chill haze or astringency, polyphenols levels can be
reduced using either or both PVPP (polyvinylpyrrolidone - trade
named Polyclar) or brewer’s gelatin as fining agents. Both act by
encouraging polyphenols to precipitate. They also have the effect of
slightly reducing polyphenolic browning, which slightly lightens the
beer’s color. Cold conditioning or lagering the beer has a similar effect
on precipitating polyphenols, but doesn’t have the lightening effect.
Aging beer also allows polyphenols to settle out of solution.
Other Sources of Polyphenols
Optional steps during the brewing process can introduce
polyphenols into your beer, as can improper sanitizing and cleaning
Bacteria: Some bacteria can produce polyphenols or promote
polyphenol production. Typically, though, these bugs also cause much
more serious off-flavors such as acetic, lactic or phenolic flavors and
aromas, making a slight astringency the least of your worries.
Cures: Use proper cleaning and sanitizing procedures for your
equipment. Make sure that your wort isn’t exposed to the open air. Don’t
siphon beer using your mouth.
Barrel Aging: Prolonged contact with wood, especially certain
varieties of oak, can extract polyphenols from the wood. Over time
however, these compounds get oxidized into other materials or are
precipitated out of solution.
Cures: Limit contact of beer with wood. Be aware that smaller and
newer barrels will impart more wood character than older and larger
barrels. When making a small batch of wood-aged beer, it is generally
better to use wood chips or wood slats rather than actually aging your
beer in a wooden barrel. Extended aging time will reduce and mellow
tannins extracted from wood.
Fruit: Almost all fruits, especially fruits with thick husks, such as
apples, bananas, cranberries, wine grapes and pomegranates contain
tannins. When making fruit beer, you must be careful not to inadvertently
extract tannins.
Cures: Avoid using parts of the fruit which are high in tannins (i.e.,
skins, pits, stems, husks and cores). Keep pasteurization temperatures
below 170 °F. Don’t add whole fruits to boiling wort. Avoid prolonged
contact of whole fruit and fermenting wort (unless the style demands it e.g., a fruit lambic).
Herbs and Spices: Herbs and spices, being plant materials, are
often potent phenol producers. A common side effect of adding herbs or
spices to your favorite beer is increased dryness due to polyphenols,
especially if you boil the materials or allow them to remain in contact with
your beer for long periods of time.
Cures: Never boil herbs or spices, including materials such as
coffee or chocolate. Instead, steep them in water of no more than 170 °F
or extract their essential oils by soaking them in vodka or grain-neutral
spirits and adding the mixture to your beer in secondary. If you can’t
extract the essences and must add them directly to your beer, put them in
a bag so that you can get all of the herbs or spices out of your beer. To
get the bag to sink, you can load it with glass marbles, which you can
easily sanitize along with the bag before you add your herbs or spices.
BJCP Category 4 - Dark Lagers
This category covers dark (brown to black) bottom-fermented beers.
While this category is mostly focused on German and German style
beers, it includes “Dark American Lagers” - this is actually something of a
catchall category for any table-strength dark lager which doesn’t fit into
any other category.
History: German Dark lagers are descended from two old brewing
The first tradition is that of pre-modern brewing, when all malt was
brown or amber malt and all beer was brown or dark brown and possibly
quite cloudy. The second tradition is that of British Porter/Stout brewing.
In the late 18th century, due to the worldwide popularity of English porters,
Continental brewers began brewing lager versions of English porters and
stouts. While English-style brown beers never became as popular in
Europe as they were in England and the British Empire (most continental
porters died out by the mid-19th century), some brands survived.
Schwarzbier (Black Beer) is a regional specialty from southern
Thüringen in northern Franconia (part of the principality of Bavaria),
particularly around the towns of Kulmbach and Bamberg. This style of
beer is related to the brown and black smoked beers (rauchbiers) for
which the region is famous, as well as more obscure styles of beer
such as Kellerbier and Zoiglebier (both cloudy, traditionally brown
farmhouse ales). A beer similar to Schwarzbier is found in Bad
Köstritz near Leipzig. It has a mellower malt profile than Franconian
schwarzbier, since it uses de-bittered roast malt, like that used to
produce Baltic porters.
Munich Dunkel is possibly a remnant of medieval and
Renaissance brewing traditions, a surviving form of continental porter,
or both. It is slightly stronger than Schwarzbier, but slightly less hoppy
and has a different flavor profile. Rather than being black, Munich
Dunkels are a mahogany brown.
Dark American Lager is a simplified version of German dark
lager, adapted to American (or industrial brewing) ingredients and
tastes. They are less complex in both hop and malt flavor than their
German counterparts, and are a bit thinner in body, making them
easier to drink. Note that Dark American Lager is something of a
catchall category, and many of the best examples are not brewed in
Some U.S. beers in this category are merely light or amber
lagers with caramel coloring added; essentially “industrial lagers
dressed in black.” These represent typical products of large
international or regional breweries. Other examples, such as Shiner
Bock, might represent historical U.S. or Mexican traditions of dark
lager beer brewing, using German brewing techniques adapted to use
local ingredients and to appeal to local consumer tastes. Finally, there
are American craft-brewed dark lagers which don’t fit into any other
category, such as Dixie Blackened Voodoo Lager.
European examples represent various dark lagers which might,
or might not, be inspired by American interpretations of German dark
beers. They include more adjunct heavy, lower alcohol variants of
bottom-fermented Baltic porter, as well as all-malt dark or brown
generic “Euro lagers” which don’t fit into the Schwarzbier or Munich
Dunkel styles. A beer possibly related to a Baltic porter is Baltika #4,
while examples such as Beck’s Dark or Warsteiner Dunkel represent
“euro dark lagers.”
Brewing Dark Lagers: German dark lagers are brewed using
Vienna or Munich malt as a base. Munich Dunkels add a bit of
chocolate and crystal malt, while Schwarzbiers add a bit of Pilsner and
Carafa malts. Both styles are decoction mashed, are hopped with
noble hops and fermented using Munich lager yeast.
Industrial dark American lagers are brewed much like American
Standard or Premium Lagers; except for a bit of caramel coloring or
chocolate malt added o darken color. They use small amounts of
noble or noble-derived hops and are fermented using American lager
yeast. European and craft brewed versions might have more complex
grist and hop bills. Some are made with a certain amount of sugar
instead of adjunct grains.
Other Dark Lagers: Don’t assume that the BJCP Guidelines
cover every style of Dark Lager! There are entire families of dark lager
beers brewed in the Austria, Czech Republic, Switzerland and
elsewhere which aren’t represented in the style guidelines. These can
be stronger or lighter, drier or sweeter, thinner or fuller bodied, darker
and/or hoppier than the listed styles and might have different malt
and/or hop character.
Also, rather than covering the continuum of dark lager styles
from weakest to strongest, the BJCP Guidelines split dark lagers up
between three categories: Dark Lagers (Category 4), Bocks (Category
5) and Porter (Category 12). If you are entering a strong dark lager
into competition, it might be judged more favorably as a Traditional
Bock (5B), Doppelbock (5C) or a Baltic Porter (12C).
Dark lagers which are probably best entered as specialty beers
(Category 23) include:
Austrian Dunkel/Doppelmalz: Based on Munich Dunkel or
Schwarzbier, but brewed to 13° Plato and attenuated to only 4.5% ABV,
meaning that they’re much fuller in body and can be extremely sweet.
Similar beers are, or were, brewed in Switzerland.
Czech 8° or 10° Dark Lagers (AKA Tmavé/Černé Výčepní Pivo,
literally, “Dark/Black Draught Beer”): Sweet and malty or dry and roasty
low alcohol (3-4% ABV) dark lagers. Some have moderate noble hop
flavor and aroma (usually Saaz hops).
Czech 11-12° Dark Lagers (AKA Tmavý/Černý Ležák Pivo, literally
“Dark/Black Lager Beer”): This is a broad class of dark lagers, some of
which fall into the category of dark American lager, Munich dunkel or
schwarzbier. Malt character ranges from quite sweet to quite dry,
sometimes with dark grain character like a conventional porter or stout.
Color ranges from light brown to black. Some can have moderate noble
hop flavor and aroma (usually Saaz hops). ABV ranges from 4.4 - 5%.
They are typically lagered for 2-3 months before packaging.
Czech 13-14° Dark Lagers (AKA Tmavé/Černé Speciální Pivo
literally “Dark/Black Specialty Beer”): Basically, an “export” strength
version of the Czech 11-12° dark lagers. They are often inspired by
Munich dunkels or schwarzbiers and are mostly produced by Czech
artisan brewers. They are usually full-bodied and malty, but have a high
degree of hop bitterness, again, usually from Saaz hops. They range from
5.3-5.8% ABV. The best known example is U Fleků Ležák.
Czech 15-17° Dark Lagers (AKA Tmavé/Černé Speciální Pivo):
Stronger versions of the above at 6 - 7% ABV. Basically, dark bock or
doppelbock beers, albeit with a different malt and hop character.
Czech 18-24° Dark Lagers (AKA Tmavé/Černé Speciální Pivo):
Even stronger versions of the above at 8 - 10% ABV. Basically, dark
doppelbocks, but some can be even stronger than traditional German
doppelbocks. Similar to these are some traditional, now rare or extinct,
Austrian and Swiss beers.
Czech Porter: Bottom-fermented, very full-bodied with lots of dark
malt character and moderate to high hop bitterness. Possibly local
interpretations of the Deutsche porter or Baltic porter styles. Before World
War 2, this represented a top-end product for Czechoslovakian breweries.
It is now quite rare.
Deutsche Porter: This is a historical 18th or 19th century style which
is nearly extinct in Germany. It has recently been revived by a few
German microbrewers and brewpubs. It seems to be a bottom-fermented
robust porter (BJCP substyle 12A) or brown porter (BJCP substyle 12B)
of 4.5-5.5% ABV. Alternately, it might be a lower alcohol, drier
interpretation of Baltic porter (BJCP substyle 12C) or a bottom-fermented
version of dry stout (BJCP substyle 13A) or sweet stout (BJCP substyle
Eastern European Dark Lagers: There are Polish, Baltic and
Russian dark lagers which are different from either Czech or German
examples. They might be weaker, more adjunct-laden versions of Baltic
porter or local interpretations of German or Czech beer styles. Many fall
into the category of dark American lager. They are usually full-bodied and
sweet with low but detectable levels of hop bitterness. Dark grain
character is usually quite subdued.
Latin American Dark Beers (AKA Malta): This category covers a
wide range of brown to black Mexican and South American beers which
roughly fall into the dark American lager style. Some can be quite sweet
and full-bodied, while others are drier and have relatively thin body. All
have very little dark grain or hop character. Note that the term Malta can
also apply to a non-alcoholic malt-based soft drink which is popular in the
4A. Dark American Lager
Aroma: Little to no malt aroma. Medium-low to no roast and
caramel malt aroma. Hop aroma may range from none to light spicy or
floral hop presence. Can have low levels of yeast character (green
apples, DMS, or fruitiness). No diacetyl.
Appearance: Deep amber to dark brown with bright clarity and
ruby highlights. Foam stand may not be long lasting, and is usually
light tan in color.
Flavor: Moderately crisp with some low to moderate levels of
sweetness. Medium-low to no caramel and/or roasted malt flavors
(and may include hints of coffee, molasses or cocoa). Hop flavor
ranges from none to low levels. Hop bitterness at low to medium
levels. No diacetyl. May have a very light fruitiness. Burnt or
moderately strong roasted malt flavors are a defect.
Mouthfeel: Light to somewhat medium body. Smooth, although
a highly-carbonated beer.
Overall Impression: A somewhat sweeter version of
standard/premium lager with a little more body and flavor.
Comments: A broad range of international lagers that are
darker than pale, and not assertively bitter and/or roasted.
Ingredients: Two- or six-row barley, corn or rice as adjuncts.
Light use of caramel and darker malts. Commercial versions may use
coloring agents.
Commercial Examples: Dixie Blackened Voodoo, Baltika #4,
Warsteiner Dunkel.
4B. Munich Dunkel
Aroma: Rich, Munich malt sweetness, like bread crusts (and
sometimes toast.) Hints of chocolate, nuts, caramel, and/or toffee are
also acceptable. No fruity esters or diacetyl should be detected, but a
slight noble hop aroma is acceptable.
Appearance: Deep copper to dark brown, often with a red or
garnet tint. Creamy, light to medium tan head. Usually clear, although
murky unfiltered versions exist.
Flavor: Dominated by the rich and complex flavor of Munich
malt, usually with melanoidins reminiscent of bread crusts. The taste
can be moderately sweet, although it should not be overwhelming or
cloying. Mild caramel, chocolate, toast or nuttiness may be present.
Burnt or bitter flavors from roasted malts are inappropriate, as are
pronounced caramel flavors from crystal malt. Hop bitterness is
moderately low but perceptible, with the balance tipped firmly towards
maltiness. Noble hop flavor is low to none. Aftertaste remains malty,
although the hop bitterness may become more apparent in the
medium-dry finish. Clean lager character with no fruity esters or
Mouthfeel: Medium to medium-full body, providing a firm and
dextrinous mouthfeel without being heavy or cloying. Moderate
carbonation. May have a light astringency and a slight alcohol
Overall Impression: Characterized by depth and complexity of
Munich malt and the accompanying melanoidins. Rich Munich flavors,
but not as intense as a bock or as roasted as a schwarzbier.
History: The classic brown lager style of Munich which
developed as a darker, malt-accented beer in part because of the
moderately carbonate water. While originating in Munich, the style has
become very popular throughout Bavaria (especially Franconia).
Comments: Unfiltered versions from Germany can taste like
liquid bread, with a yeasty, earthy richness not found in exported
filtered dunkels.
Ingredients: Grist is traditionally made up of German Munich
malt (up to 100% in some cases) with the remainder German Pilsner
malt. Small amounts of crystal malt can add dextrins and color but
should not introduce excessive residual sweetness. Slight additions of
roasted malts (such as Carafa or chocolate) may be used to improve color
but should not add strong flavors. Noble German hop varieties and
German lager yeast strains should be used. Moderately carbonate water.
Often decoction mashed (up to a triple decoction) to enhance the malt
flavors and create the depth of color.
Commercial Examples: Paulaner Alt Münchner Dunkel, Hofbräu
4C. Schwarzbier (Black Beer)
Aroma: Low to moderate malt, with low aromatic sweetness and/or
hints of roast malt often apparent. The malt can be clean and neutral or
rich and Munich-like, and may have a hint of caramel. The roast can be
coffee-like but should never be burnt. A low noble hop aroma is optional.
Clean lager yeast character (light sulfur possible) with no fruity esters or
Appearance: Medium to very dark brown in color, often with deep
ruby to garnet highlights, yet almost never truly black. Very clear. Large,
persistent, tan-colored head.
Flavor: Light to moderate malt flavor, which can have a clean,
neutral character to a rich, sweet, Munich-like intensity. Light to moderate
roasted malt flavors can give a bitter-chocolate palate that lasts into the
finish, but which are never burnt. Medium-low to medium bitterness, which
can last into the finish. Light to moderate noble hop flavor. Clean lager
character with no fruity esters or diacetyl. Aftertaste tends to dry out
slowly and linger, featuring hop bitterness with a complementary but
subtle roastiness in the background. Some residual sweetness is
acceptable but not required.
Mouthfeel: Medium-light to medium body. Moderate to moderately
high carbonation. Smooth. No harshness or astringency, despite the use
of dark, roasted malts.
Overall Impression: A dark German lager that balances roasted
yet smooth malt flavors with moderate hop bitterness.
History: A regional specialty from southern Thüringen and northern
Franconia in Germany, and probably a variant of the Munich Dunkel style.
Comments: In comparison with a Munich Dunkel, usually darker in
color, drier on the palate and with a noticeable (but not high) roasted malt
edge to balance the malt base. While sometimes called a “black pils,” the
beer is rarely that dark; don’t expect strongly roasted, porter-like flavors.
Ingredients: German Munich malt and Pilsner malts for the base,
supplemented by a small amount of roasted malts (such as Carafa) for
the dark color and subtle roast flavors. Noble-type German hop varieties
and clean German lager yeasts are preferred.
Commercial Examples: Köstritzer Schwarzbier, Kulmbacher
Mönchshof Premium Schwarzbier, Samuel Adams Black Lager, Gordon
Biersch Schwarzbier.
Vital Statistics
4A. Dark American Lager
4B. Munich Dunkel
4C. Schwarzbier (Black Beer)
Sub-Style Comparison Table
4A. Dark American Lager
Aroma: Malt aroma usually more subdued, less complex. Can
have low levels of yeast character (DMS, acetaldehyde, diacetyl,
Appearance: Lightest color (dark amber to medium brown),
lower, less-persistent head.
Flavor: Lighter, less complex malt character. Low-medium
sweetness. Very low-medium low hop bitterness. Some DMS, esters
Mouthfeel: Thin-medium thin body. Highly carbonated.
Overall: Highest alcohol (up to 6% ABV), lowest IBU (8-22),
lowest FG (1.008-1.012), lightest color (8-20 SRM). Can use adjuncts
or coloring agents.
4B. Munich Dunkel
Aroma: Rich, complex bready Munich malt. No yeast character.
Appearance: Unfiltered hazy versions OK.
Flavor: Rich, complex bready Munich malt. Can be somewhat
sweet. No harsh roasted or sweet caramel malt notes. Hop bitterness
detectable, but low. Clean yeast character.
Mouthfeel: Medium to medium-full body. Light astringency OK.
Slight alcohol warmth OK.
Overall: Not as strong as a bock or as roasted as a
schwarzbier. Roastier and darker than a Märzen. Mostly uses Munich
4C. Schwarzbier
Aroma: Low-medium malt aroma, can be clean and neutral or
rich and Munich-like. No burnt notes. Low DMS OK.
Appearance: Darkest color (brown to dark brown). Never black.
Large persistent head.
Flavor: Low-medium malt flavor, can be clean and neutral or
rich and Munich-like. No burnt notes. Medium-low to medium hop
bitterness. Clean yeast character. Dry, lingering finish.
Mouthfeel: Medium-light to medium body. Medium to medium
high carbonation. No astringency.
Overall: Darkest color (17-30 SRM), highest IBU (17-32).
Darker, drier and slightly roastier than Munich Dunkel
Aroma: No to low noble hop aroma. Can have caramel & roast
malt notes. No-low yeast character.
Appearance: Usually clear. Ruby highlights, tan head.
Flavor: Generally restrained dark malt character. Not
excessively sweet. No to low noble hop flavor. Generally clean yeast
Mouthfeel: Medium to high carbonation.
Inspirational Reading
Books & Magazines
Daniels, Ray. Designing Great Beers, Brewer’s Publications, Boulder, Co.
Fix, George. Principles of Brewing Science, Brewer’s Publications, Boulder, Co.
Mosher, Randy. Radical Brewing, Brewer’s Publications, Boulder, Co.
Noonan, Greg. New Brewing Lager Beer, Brewer’s Publications, Boulder, Co.
Palmer, John. How to Brew, Brewer’s Publications, Boulder, Co.
Snyder, Stephen. The Brewmaster’s Bible, Harper-Collins Press, New York, NY.
Zainasheff, Jamil & Palmer, John, Brewing Classic Styles, Brewer's Publications, Boulder, Co.
Zymurgy, Jan/Feb, 2008, p. 15. Crafting Dark Lagers, Amahl Turczyn Scheppach.
Web Sites
Understanding Malt Analysis Sheets
Understanding Malt Spec Sheets: Advanced Brewing (
Acronyms and Abbreviations Used in Beer & Brewing Discussions (
Malt Analysis Sheets, etc.
Lot Analysis Program (
Typical Analysis (
Know Your 2010 Malting Barley Varieties (
Tannin Chemistry (
Tannins (
Dark Lagers
Blackened Voodoo Lager ( (recipe)
Dunkel (
Dunkel (
Dunkel - The first beer-purity-law lager (
Schwarzbier (
Schwarzbier (
Schwarzbier ( (Recipe)
Schwarzbier - The 'stout' of lagers (
Shiner Bock recipe ( (recipe)
The 10 Hardest Beer Styles (
European Beer Guide (