Barley Flashcards
Barley Latin name
Hordeum vulgare L.
World production
4th among cereals in annual world production.
3rd largest valued crop in Canada
Utilization
75% feed
20% malt
5% food
5% seed
What are Market Classes Based on
Based on. end-use – malting, food, or general purpose.
Types of Barley
Covered/Hulless, 2-row/6-row
Hulless Barley
there’s some production of hulless barley in Canada.
- lower in fibre
- higher in energy & protein
- lower transportation cost
Barley Kernel Characteristics
Hull - 10%
Bran -10%
Endosperm - 77%
Germ - 3%
usually lower in protein than wheat.
starch high in beta gluten
Barley varieties based on starch characteristics
normal (25% amylose)
waxy (0.5% amylose)
high (40% amylose).
Waxy, hulless types have the highest beta-glucan levels.
How Is Barley Processed for Food?
Pearling (abrasion milling) grinds off hull, bran, and germ.
Yields pot and pearl barley for use in soups, flour, pancake mix, cereals.
Abraded fractions are used as feed.
Why is Barley not super common in food?
there are problems: there is no gluten functionality and there are colour and flavour defects.
Why is Beta-Glucan of interest to the food industry?
Beta-glucan is a source of soluble fibre linked to a number of health benefits.
Concentrates can be isolated by dry air fractionation of barley flour to add to bakery products to increase fibre.
Is Barley ever Wet Milled?
Yes – Wet Milling of barley has been commercialized. Starch and beta-glucan are the major products.
What is “Malting”?
Malting: the controlled, restricted germination of barley followed by drying (kilning).
Why is Barley used for Malting?
barley’s tough hull protects the acrospire, maintains firmness when adding moisture, and helps filter during brewing. Barley has all the needed enzymes for the malting process
What is the Goal of Malting?
To produce high enzyme activity.
To modify the endosperm.
To develop flavour.
All while minimizing losses of dry weight.
What enzymes does barley germination induce?
Alpha and Beta amylase, Beta-glucanase, and proteases are all activated during germination in the malting process.
Plumpness
Before Malting, barley is separated into three classes: thin, plump, and very plump depending on endosperm content and moisture uptake.
Thin barley is sold as feed. plump and very plump are used in the malting process.
Malting Steps
- Cleaning - Removal of foreign material and plumpness classification.
- Steeping - moisture raised to 45% to achieve uniform germination in self-emptying steep tanks. 10-15º, 2 days.
- Germination - placed in beds to germinate 3-4 days. agitated with cool air (15º, 100% rh). germinates until shoot is 2/3 to 3/4 length of kernel. green malt.
- Kilning - drying green malt at 50-60º halts growth, allows safe storage, develops flavour and colour. Rootlets (culms) removed by scouring.
Utilization of Malt
- mostly in brewing
- as malt flour for baking (amylase activity)
- as malt extract (syrup) in baking for flavour & sweetness.
non diastatic Is just for flavour and colour.
diastatic is for active enzymes and flavour.
Brewing
the fermentation of cereal grains to produce beer
How do you make ethanol?
Starch –> Maltose & Glucose –> ethanol.
what is involved in brewing?
Malt (usually barley), adjuncts (usually), water, hops, and yeast.
What are Adjuncts and when are they used?
Adjuncts: when a paler, milder flavoured beer is desired, a non-malt source of fermentable carbohydrate can be used. Enzymes from the malt cover the malt and adjunct starch to fermentable materials.
What needs to happen to the Malt before the actual brewing process?
the malt’s particle size needs to be reduced. the malt consists of intact kernels. need to reduce endosperm to a fine particle via wet/dry milling. the goal is to maintain the hull and bran in large pieces.
Name the Brewing Steps
- Mashing
- Filtering (lautering)
- Boiling
- Fermenting
Step 1 of Brewing
Mashing – steep the ground malt/adjunct in hot water (70ºC) in mash tank (tun). starch breaks down and release amylose and amylopectin which are converted to fermentable sugars (maltose & glucose) by amylase enzymes (alpha and beta amylase). the sugars, dextrins, amino acids, protein dissolve. the hulls/bran (insolubles) sink to bottom when agitation ceases.
Step 2 of Brewing
Filtering – solubles (sugars, dextrins, amino acids and proteins) are recovered by filtration of mash over the bed of hulls/bran. filter bed washed with hot water to recover more solubles. What’s left is called sweet wort. The insolubles are called brewer’s grain.
Step 3 of Brewing
Boiling – Wort is boiled to insolubilize protein and stop enzyme activity. Boiling also extracts flavour from added hops and sterilizes. Boiled wort is chilled to precipitate protein and is filtered
End product is hopped wort.
Step 4 of Brewing
Fermentation – west is added to hopped wort (pitching). It is then aerated to aid yeast growth (2 days). It is then fermented under anaerobic conditions to convert maltose and glucose to ethanol, CO2, acids, and heat (3-5 days)
Step 5 of Brewing
Post-Fermentation – fermented wort is drawn from the yeast, chilled to precipitate protein, and filtered (green beer). Beer is aged and then pasteurized or sterilized.
Where do hops come from
female flowers of humulus lupulus
High Quality Malt
high germination capacity***
low hull content
low in protein
Whiskey
retains the flavour and colour developed during production due to mash ingredients, flavour ingredients, aging, and blending
Neutral Spirits
Vodka and grain alcohol. colour and flavour are removed.
How do potable spirits differ from beer process
the entire mash is fermented without separation of wort from the insolubles. fermented mash is then fractionally distilled.
What does fractionally distilled mean?
The separation of liquids on the basis of differences in their boiling points. Yields products containing 40-50% alcohol (80-100 proof). By-product is distiller’s grain.
Manufacture of Fuel Alcohol
mash of low-cost carbohydrates. uses bacterial and fungal enzymes in place of malt.
fermented mash is fractionally distilled. product is 95% ethanol (azeotrope) or 100% ethanol when rectified using a molecular sieve or dehydrating agent.
