Barley Malt - an overview

Most common source of
fermentable sugars in beer
– Grass family Gramineae
– Species Hordeolum vulgare
– formed by sprouting barley
kernels to a desired length,
stripping off the rootlets,
and drying to a specific
color
Barley Malt oveview
(continued)

Parts of the Kernel
– germ (actual growing part
of the kernel)
 Acrospire- above
ground portion
 Rootlet - below ground
portion
– endosperm (starch food
supply for the germ)

needs to be converted to
sugar for brewing
– husk (cellulose protective
cover)
Types of Barley

Two row barley
– only two of the six flower rows are fertile and
able to produce kernels

Six row barley
– all six rows are fertile and produce kernels

Four row
– actually a six row intermediate, not widely used
in brewing
Differences in barley types

Two Row

Six Row
– bigger kernels, higher
– more yield per acre
yield per head
– lower protein
(nitrogen) content
– lower husk contents
(less grainy flavor)
– less enzymes
– more diastatic power
ie. enzymes (better
when using lots of
adjuncts)
– higher husk level
makes for better
lautering filter bed
2-Row
2-Row
6-Row
6-Row
Purposes for malting
1.
2.
3.
Convert the large chains of insoluble starch in
the endosperm to short chain water-soluble
starches
Break down proteins in the barley by activating
Proteolytic (“protein breaking”) enzymes
Activates the diastatic (“carbohydrate breaking”
enzymes that will convert starches to sugars
during mashing
Malting enzymes (continued)

Cytases (hemicellulases & B-gluconsases)
– Occur during germination, not malting
 break down husk cell walls
 allow the diastatic enzymes to work more easily
during the malting process

Dextrase
– Break the large starch chains at the 1-6 links to
make smaller polysaccharide chains
Malting Enzymes (continued)

Diastatic enzymes
– α-amylase
 breaks the 1-4 links in the middle of the α-glucans
starch to make smaller starch chains
– β-amylase
 breaks the smaller starch chains into maltose sugar
by breaking 1-4 links near the reducing ends of the
smaller chains
Glucose molecule
Where α-amylase
works
Maltose molecule
Modification

Sprouting the grains to correct modification
– Acrospire grows from the germ end of the
kernel toward the opposite end
– Length ratio of acrospire to the kernel
determines the level of modification
Malting is a three-step process
1)Steeping
2) Germination
3) Drying
Primary
Immersion
Phase
Drain &
Air Rest
Phase
Spray or
Additional
Immersions
Steep
Out
Objective
is to
obtain
uniform
germinati
on or
“chitting”
Germination
Germination,
which began
in the steep
tank,
continues in
the
compartment
where the
barley
undergoes
modification.
Control Points
In Germination
•Kernel Moisture
•Piece
Temperature
•Time
Objectives of
Kiln Drying
•Stop growth and
modification
•Preserve enzymatic activity
•Create shelf stability
•Create colors and flavors
Milling
Weighin
g
Mashing /
Conversion
Separatio
n/
Boiling
Evaporatio
n
Environmentall
y
controlled
packaging
process
Bulk
Loading/
Unloading
Malting Process (continued)
Barley steeped in 50-65o F water for two- three days
 Kernels allowed to germinate between 50-70o F for six to
ten days (Acrospire reaches 50% length about day 6)
 Malt temp raised gradually to 90o F and held there for 24
hrs. (allows enzyme action)
 Malt temp then gradually raised to 120o F and held there
for 12 hours to dry the malt
 Malt must be bone dry before kilning

Modification- a definition

The degree of germination a barley kernel
achieves during the malting process.
– the degree to which the protein/gum matrix of
the starch in the kernel is broken down
– increases the amount of proteins which will
become soluble in water
Modification (continued)

Modification is achieved through the
malting process
 Varies from under-modified to highly
modified malts
 Modification is affected by
– the strain and type of barley used
– the malting process itself
Differences in Modification

Under-modified
– more complete set of enzymes
– more proteins that will require
additional protease enzymatic
breakdown to avoid the
protein-polyphenol induced
haze (“chill haze”)

Highly modified
– high level of protein
degradation
– doesn’t require a long protein
rest
– may not necessarily be suitable
brewing all styles of beer
Modification: Example 1

Fully modified - Ratio 1.0
– Acrospire as long as the kernel
– will have a low protein content
– endosperm (starch) almost fully water soluble
– Some of the endosperm is lost as it was used by
the acrospire to grow to this length. That
equates to less potential yield of fermentable
sugar
Modification: Example 2

75% Modification
– Acrospire is 3/4 the length of
the kernel
– more of the endosperm is
retained for fermentation
availability
– more protein remains (adds
complexity to the beer)
– the expense is that there is
reduced diastatic enzyme
activity for mashing
>75%
Degrees of Modified Malts

Continental

American 6-row
– 50-75% modified
– Fully modified
– retains more
– because of higher
endosperm for
fermentation
– creates more protein
complexity but:
– at the expense of
reduced enzyme
activity
protein content, has
greater enzymatic
strength than
Continental
Degrees of modification
(cont.)

Both Continental and American malts
require a protein rest at about 122o F to
degrade albuminous proteins
– promotes yeast growth
– aids in head retention
Degrees of modification
(cont.)

Caramel & Crystal

Chocolate & Patent
– fully modified
– under modified (<50%)
– kilned at 50% moisture
– do not require protein
(not bone dry)
– This essentially mashes
the starch directly
inside the kernel husk
rest, as the kilning
process degrades the
starches
Kilning


Kilning is roasting the malt to
achieve the proper color and other
characters of a particular malt
– Raising the temperature of the
dried malt to a particular level
– Creates flavor and bodybuilding melanoidins from the
amino acids and malt sugars in
the malt
Degree of modification + kilning =
type of malt
Kilning (continued)

Pale Malts (British & American)
– Kilned between 130o and 180o F

Vienna Malt
– low kilned at around 145o F

Czech Malts
– raised slowly from 120o to 170o F, then roasted
at 178o F
Kilning (continued)

Dortmunder & Munich malts
– kilned at low temperature, then raised before the malt
has dried to 195-205o F (Dortmunder) or 210-244o F
(Munich)

Amber malt
– well modified, then dried and rapidly heated to 200o F.
– Temp then raised to 280-300o F and held until desired
color is reached
Kilning (continued)

Crystal & Caramel
– fully modified, then kilned at 50% moisture
– Temp raised to 150-170o F and held for 1.5 to 2
hours
– Essentially mashes the endosperm inside the
husk
– Heated to final roasting temp, time/temp
determines final Lovibond color index
Kilning (continued)

Chocolate & Patent Malts
– dried to 5% moisture
– roasted at 420-450o F for up to two hours
– high heat degrades the starch so no protein rest
is needed
– can also be roasted over beechwood fires
(Bamberg style)
Kilning (continued)

ALL malts
– Once the malt is evenly roasted, they are
cooled to 100o F
– Placed in a rotary bin (or some other method)
and rootlets are removed
– Malt needs to rest for at least one month before
mashing
Other Malted Grains

Wheat
– has enough diastatic power on its own, but not
enough husk to effectively lauter on its own
– high protein & β-glucan content compared to
barley, needs longer protein rest if used in large
quantities

Rye, Oats, Sorghum - sometimes malted,
usually used in raw form
Barley Contents

Sugars & Starches- converted to sugars
during mashing
 Enzymes - a type of protein, influences
protein content of the mash, too!
 proteins- food for the germinating acrospire
Barley Contents (continued)

free nitrogenous compounds
 B-complex vitamins- needed for yeast
development
 Phosphates - necessary for acidification of
the mash & used by yeasts
Barley contents (continued)

Trace Elements
– Tannins
– cellulose
– polyphenols
 components of the husks
 can cause harsh flavors in beers if leached out by hot
or alkaline sparge water
Barley contents (continued)

Fatty acids & lipids
– support respiration of the embryo during
malting
– can create oxidative flavors and low head
retention if excessive levels carry into the wort

Hemicellulose & soluble gums
– must be reduced by enzymes to permit head
retention, else may cause clarity problems
Categories of
Specialty Malts
•Kiln Produced
•Roaster
Produced
Kiln Dried,
Roasted
Malts
Victory®
Special Roast
Chocolate
Dark
Chocolate
Black
Roasted
Barley,
Black
Barley
Cereal Adjuncts

Cheap source of carbohydrates with minimal
protein addition
 Must be gelatinized before mashing - preliminary boil
or flaking through hot rollers
– corn (maize)- heavy use in Amer. light lager
– rice grits - heavy use in Amer. light lager
– sorghum
– flaked barley, rye, and wheat
Other Adjuncts

Corn sugar
 Cane sugar
– fully fermentable, cheap, produce more EtOH
and drier beer
– cidery flavors tend to be produced due to the
enzymes used by the yeast to metabolize the
sucrose
Other adjuncts (continued)

Honey
– common in specialty beers
– contributes some aromatics
– tends to make beer thinner and more alcoholic
due to high sugar content
Other adjuncts (continued)

Malto-dextrin
– syrup or powder
– adds body or “mouth feel” to beer

Caramel
 Molasses
 Maple syrup
 licorice
Color

Determined by types of malts used
 Important characteristic of styles
 Two scales
– EBC (Europe)
– SRM (USA)

Low (light color) to high (black)
Color (continued)

Amer. Lite Lager: 2 to 4 SRM
 Pilsner: 3-5 SRM
 Oktoberfest: 5-14 SRM
 Doppelbock: 20-30 SRM
 Stout: > 50 SRM