MALTING QUALITY TRAITS - Canadian Malting Barley Technical ...

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Chapter Two
Selection Criteria
Since quality specifications of the selected barley have a direct influence on the malt
quality, barley selectors place great emphasis on the selection criteria. Though quality
specifications may vary somewhat between malting companies, the following quality
criteria remain the same to ensure a high quality malting barley is being selected.
Varietal Purity
Varietal purity is an important factor in order to produce malt with high
homo-geneity and uniform quality traits. This is because different malting barley
varieties require different processing conditions.
Germination and Vigorous Growth
High percentage germination and vigorous growth are key quality factors during the malting
process. At least 95% germination is required for malt production.
Kernel Size
High plumpness and uniform kernel size are desirable quality characteristics
since potential malt extract is directly associated with barley kernel size. Minimum
requirements for official CGC primary (grower) grades are specified at 85% over 6/64” slotted
screen for special select two-rowed malting barley varieties and 75% over 6/64” for special select
six-rowed varieties.
Barley Protein Content
Barley protein content affects the chemical composition and enzyme levels of the
malt. It should be high enough to provide enough enzymes for malting and mashing,
sufficient nutrients for yeast growth and sufficient peptides for beer head retention.
If too high, however, it will cause beer stability problems. A preferred protein range for two-rowed
Canadian barley is from 10.0 to 13.5%, and for six-rowed malting barley it can be slightly higher.
Barley Moisture Content
Barley moisture content is an extremely important quality parameter.
A moisture content of more than 13.5% is unacceptable as too much moisture may result
in infestation, mould growth and viability loss during storage and transportation.
Customers also prefer a lower barley moisture content for economic reasons.
Peeled and Broken Kernels
No more than 5% of the kernels should be peeled or broken, as husk and
kernel damage affect the uniformity of barley water uptake during steeping and the
barley’s viability (too much water is absorbed and the soggy kernels may not germinate).
Husk and kernel damage often occurs during combining, auguring or conveying during
handling. In addition, the degree of husk damage is varietal dependent, and some
varieties have better husk adherence than others.
No Desiccant Treatment
Barley selected for malting should not be treated with any pre-harvest desiccant.
Desiccant treated barley is not accepted by malting and brewing companies, and is not accepted
under the terms of the malting barley selection contract.
Visual Inspection
Visually, barley kernels should be bright, healthy and fully matured. They should be free from
disease, heat and frost damage, and not weathered or deeply stained. Also, the barley kernels should
be free of insects, large oil-bearing seeds, ergot, treated seeds, smut and odour, and have no sign
of pre-germination.