Barley Malt - an overviewBarley 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 Barley Malt oveview (continued)(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 BarleyTypes of Barley

Two row barley– only two of the six flower rows are fertile and

able to produce kernelsSix row barley

– all six rows are fertile and produce kernelsFour row

– actually a six row intermediate, not widely used in brewing

Differences in barley typesDifferences in barley types

Two Row– bigger kernels, higher

yield per head– lower protein

(nitrogen) content– lower husk contents

(less grainy flavor)– less enzymes

Six Row– more yield per acre– more diastatic power

ie. enzymes (better when using lots of adjuncts)

– higher husk level makes for better lautering filter bed

2-Row

6-Row2-Row 6-Row

Purposes for maltingPurposes for malting

1. Convert the large chains of insoluble starch in the endosperm to short chain water-soluble starches

2. Break down proteins in the barley by activating Proteolytic (“protein breaking”) enzymes

3. Activates the diastatic (“carbohydrate breaking” enzymes that will convert starches to sugars during mashing

Malting enzymes (continued)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)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 moleculeGlucose molecule

Where Where α-α-amylaseamylase worksworks

Maltose moleculeMaltose molecule

ModificationModification

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

PrimaryImmersion

Phase

Drain &Air Rest

Phase

Spray orAdditional

Immersions

Objectiveis to

obtainuniform

germination or

“chitting”

SteepOut

Germination, which began in the steep

tank, continues in

the compartment

where the barley

undergoes modification.

Germination

•Kernel Moisture

•Piece Temperature

•Time

Control PointsIn Germination

•Stop growth and modification•Preserve enzymatic activity•Create shelf stability•Create colors and flavors

Objectives ofKiln Drying

Milling

Weighing

Mashing / Conversion

SeparatioSeparation/n/BoilingBoiling

Evaporation

Environmentallycontrolledpackagingprocess

Bulk Loading/Unloading

Malting Process (continued)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 definitionModification- 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 (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 ModificationDifferences 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 1Modification: 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 2Modification: 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 MaltsDegrees of Modified Malts

Continental– 50-75% modified– retains more

endosperm for fermentation

– creates more protein complexity but:

– at the expense of reduced enzyme activity

American 6-row– Fully modified– because of higher

protein content, has greater enzymatic strength than Continental

Degrees of modification Degrees of modification (cont.)(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 Degrees of modification (cont.)(cont.)

Caramel & Crystal– fully modified– kilned at 50% moisture

(not bone dry)– This essentially

mashes the starch directly inside the kernel husk

Chocolate & Patent – under modified

(<50%)– do not require protein

rest, as the kilning process degrades the starches

KilningKilning 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 body-building melanoidins from the amino acids and malt sugars in the malt

Degree of modification + kilning = type of malt

Kilning (continued)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)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)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)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)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 GrainsOther 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 ContentsBarley 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)Barley Contents (continued)

free nitrogenous compoundsB-complex vitamins- needed for yeast

developmentPhosphates - necessary for acidification of

the mash & used by yeasts

Barley contents (continued)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)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

•Kiln Produced

•Roaster Produced

Categories ofSpecialty Malts

Kiln Dried,Roasted

Malts

Victory®Special Roast

ChocolateDark

ChocolateBlack

RoastedBarley,

BlackBarley

Cereal AdjunctsCereal 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 AdjunctsOther Adjuncts

Corn sugarCane 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)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)Other adjuncts (continued)

Malto-dextrin– syrup or powder– adds body or “mouth feel” to beer

CaramelMolassesMaple syruplicorice

ColorColor

Determined by types of malts usedImportant characteristic of stylesTwo scales

– EBC (Europe)– SRM (USA)

Low (light color) to high (black)

Color (continued)Color (continued)

Amer. Lite Lager: 2 to 4 SRMPilsner: 3-5 SRMOktoberfest: 5-14 SRMDoppelbock: 20-30 SRMStout: > 50 SRM