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XII. Quality Testing Procedures Used to Develop Acceptable Malting Barley Varieties

XII. Quality Testing Procedures Used to Develop Acceptable Malting Barley Varieties

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MALTING BARLEY IN THE UNITED STATES



361



varieties. In many barley breeding programs a series of tests for quality

are used. The complexity and number of determinations of the tests increases as the amount of grain available for testing and homozygosity of

lines increases with advancing generations. Also, the number of hybrid

selections which can be evaluated in later generations becomes less because

of the complexity of the tests and expense involved. Selection based on

the preliminary tests aids in reducing numbers of selections in advanced

generations.

The purpose of this section is not to give a detailed discussion of the

methods used in evaluating barley or malt, but to illustrate the steps a

barley breeding team usually follows from making the initial cross to final

naming and releasing of an acceptable malting variety.

Methods for barley quality evaluation were reviewed by Dickson and

Burkhart (1956) and Dickson (1965). Meredith et al. (1962) extensively

reviewed the methods of quality evaluation used for barley and malt in

several of the quality laboratories in Canada, the United States, and

Europe. Dickson (1969) discussed tests used for malting quality, and Anderson et al. (1943) extended such information to include an interpretation of analytical data on barleys and malts with this interpretation helpful

to plant breeders in their selection programs.

New methods of quality evaluation are constantly being investigated and

incorporated into testing procedures on hybrid selections as new basic biochemical and physiological information becomes available. Much effort by

quality laboratories involves improvement in the efficiency and speed with

which barley selections can be analyzed for quality. The success of a malting barley breeding program is closely related to the number of barley

selections which can 'be evaluated for quality along with agronomic and

disease characteristics. The ability of small-scale quality tests to aid the

barley breeder in selecting for quality characteristics can only be determined by their relationship to plant scale malting and brewing tests.

A.



PREDICTION

TEST



The prediction test involves the determination of protein content, potential diastatic power, and percent extract on the barley grain. Kernel size

assortment also is determined using the standard %4 inch X % inch and

the %;4 inch x % inch sieves. Although 60 g are submitted for the prediction tests, actual evaluations usually involve only 36 g of barley grain. The

prediction test is conducted on grain from individual plant progenies normally beginning in the F, generation and may continue until the F, or

as long as selections are carried as individual lines. Barley in any generation

can be analyzed by the prediction test. However, Foster et al. (1967) have



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G. A. PETERSON AND A. E. FOSTER



shown that use of the method was ineffective for selection on an individual

F, plant basis.

Bendelow and Meredith ( 1955) have described prediction test procedures based on several earlier studies conducted by Canadian researchers.

Results of a micro method of extract determination using 3.5 g of barley

correlated well with the results of prediction tests normally using 20 g

(Banasik and Harris, 1959). This micro method for extract determination

could be used for very small samples, but normally individual plant progeny rows furnish sufficient grain for the 20 g test. A computer evaluation

system for the barley prediction data has been designed to provide greater

uniformity of laboratory results (Banasik et al., 1966). The more rapid

compilation of the data has been of great benefit to the program.

B.



MACROAND MICROMALTING



The macro malting test normally is used on barley selections upon their

initial entry into performance trials which include grain yield determinations. Although the macro malting test often is initiated on F, selections,

tests beginning with F, to F, generation lines are more common. The

macro malt quality evaluations continue as rong as barley selections are

retained in small plot or rod-row type performance trials. The USDA

National Barley and .Malt Laboratory uses the macro malt test on entries

of the several regional nurseries grown throughout the United States. Approximately 250 g of barley are malted, and determinations are made according to standardized procedures which have been developed by the

American Society of Brewing Chemists (Anonymous, 1958). The characteristics listed in Table I11 are obtained from the macro malt analysis. In

addition, kernel discoloration, malt recovery, percent of total protein that

is soluble, and p-amylase often are reported.

Banasik et al. (1956) developed a micro malting method which modified some of the steps in the macro malting procedure without an appreciable loss in the accuracy of the determinations. The changes primarily involved modification of the steeping process, a 3-day germination period

instead of 5 or 6 days, and a two-stage kilning process. A major advantage

of the micro malting method is the use of only 60 g of barley grain. Often

in preliminary performance trials of barley selections, the amount of available grain may be a limiting factor for the macro malting test. The Department of Cereal Chemistry and Technology at North Dakota State University is using the micro malting test on barley selections in preliminary and

advanced performance trials. Wort color and p-amylase are two of the

characteristics that are not obtained by the micro malt test, but are determined in the macro malts.



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An automated analysis for both malt diastatic power and @-amylaseactivity that was recently reported (Banasik, 1971) is being used on a

routine basis. This modified procedure has shown precision equal to manual procedures and has greatly decreased the time required for the determination of these enzymes. The computer evaluation and compilation of

malting quality data (Banasik et al., 1966) mentioned previously for barley quality data also are being used. These modifications are helpful in

a barley breeding program because the time period from submitting samples for quality testing to the need for the quality data to make selections

for planting of the promising lines is relatively short.

Micro brewing methods which only require 120 g of barley grain are

available. This micro brewing evaluation has been used on advanced barley

selections in performance trials at North Dakota State University, but the

number of selections which can be handled is limited. The micro brewing

data do assist in making quality decisions on the advancement of barley

selections in a breeding program.



c.



PILOT MALTINGAND BREWING



Pilot-scale malting and brewing tests are conducted in industry laboratories. These tests are attempts to obtain quality results which simulate

plant-scale operations. Only the most promising barley selections from

plant breeding programs are submitted to the Malting Barley Improvement

Association for distribution to various industry participants which collaborate in the pilot-scale malting and brewing tests. The physical and chemical

properties of the barley, malts, and brews which are determined are the

same as those determined from plant scale operations. These characteristics from malting have been discussed by Witt (1970) and from brewing

by Ohlmeyer and Matz (1970).

Industry laboratories which pilot malt generally use 1 to 10 pounds of

barley. Industry collaborators which perform pilot-scale tests on both malts

and brews generally require 12-30 pounds. Appropriate checks are submitted along with the advanced selections. Usually not more than five barley selections are submitted from any, single breeding program. Pilot malting and brewing are conducted on barley lines which show considerable

promise for agronomic and disease characteristics in tests over locations

and years. Pilot scale testing usually is conducted only for a one-year

period but can extend beyond this time. Usually the agricultural experiment

stations submit one bushel of barley from one or more locations on which

preliminary evaluation for protein content, kernel plumpness, and kernel

discoloration are satisfactory. An overall performance rating of the barley

selections, and a recommendation regarding further advancement is made



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G. A. PETERSON AND A. E. FOSTER



through a technical committee of the Malting Barley Improvement Association to the breeder for his consideration.



D. CARLOTQUALITYEVALUATION

The final step in the quality evaluation of a barley selection is carlot

testing on a plant scale basis. Selections do not reach this stage unless

they show very great potential as a barley variety. This quality evaluation

is made by industry through coordination with the Malting Barley Improvement Association. The handling of experimental barleys usually is

similar to that of commercial malting operations, and direct comparisons

with commercially grown check varieties are made. The amount of grain

needed for a plant-scale evaluation depends on a particular malting company, but a minimum of 2000 bushels generally is required. Usually a maximum of approximately 10,000 bushels is desired by the Malting Barley

Improvement Association for these tests. As with the pilot-scale evaluation,

an overall evaluation and a recommendation regarding further testing is

made by a technical committee of the Malting Barley Improvement Association. Final acceptance or rejection is made by the full membership of

this organization. The recommendation for acceptance is made on satisfactory performance on a plant scale basis for two years or two of three years.

Rejection can be based on one or more years of unacceptable performance.

Naming and release of an acceptable malting barley is done by the agricultural experiment stations upon consideration of the complete results

from agronomic, disease, and quality evaluations. Usually 10 to 14 generations have been grown before naming and release. The minimum time from

the initial cross to release of an acceptable malting barley variety is eight

years. The minimum number of years is less than the minimum number

of generations because winter greenhouse crops and winter increases in

Mexico or the southern United States makes possible the growth of more

than one generation per year.

XIII.



Malting Barley Production Practices



Although the barley grower cannot be assured of producing a crop suitable for malting barley, there are several important management decisions

which affect his chances of success. Many of the practices recommended

for the production of barley for feed or seed also apply to its production

for malting barley (Shands and Dickson, 1953; Reid et aZ., 1968; Hunter,

1962). Maximum grain yields of bright, plump kernels produced under conditions that provide minimum losses due to weeds, diseases, and insects

are a common goal. However, some of the decisions involved in the pro-



MALTING BARLEY IN THE UNITED STATES



365



duction of barley for the malting market are more critical than for other

uses because the physical and chemical properties of the harvested grain

are of primary concern in the market.

Three general considerations confront a producer interested in growing

acceptable malting barley. First, the area of production must have the potential of growing grain of suitable quality. This factor is largely a matter

of environment, and past climatic history should provide the answer. There

are new frontiers for malting barley where history may be of little value

in determining successful production. However, these are small in number

and generally are associated with new irrigation developments or areas

where cropping practices can be changed in established irrigation districts.

Second, adapted barley varieties of acceptable quality must be available.

Third, a market for malting barley must be available. After these general

criteria have been met, several specific management decisions remain.

The general requirements of malting barley have been known for a long

time in relation to the period of time that this crop has occupied an important place in American agriculture. Information on barley production practices was summarized by Derr (191 1) and in bulletins by Harlan (1918,

1932) and Harlan and Wiebe (1943). Each of these authors referred to

culture of malting barley. Most states with significant malting barley acreages have published results on production practices and made these available to barley growers through extension bulletins and circulars. Although

some of the recommended practices have been modified as new research

data have been published, it is interesting to note the validity of recommendations made several decades ago to malting barley producers.

A.



CHOICE

OF VARIETY



Selection of a variety by a malting barley grower involves two major

considerations. First, the variety must be adapted to the area and should

have as many of the agronomic characteristics as possible to fit the specific

conditions provided by the individual grower’s farming operations.

Medium to late maturity in spring barley for early sowing, in order to utilize more of the growing season, and resistance to loose smut [Ustilago

nuda (Jens.) Rostr.] are examples of specific characteristics that may be

used in varietal decisions. Second, the variety must have the potential as

a suitable raw material for malt. The various agricultural experiment stations in states with malting barley breeding programs collaborate with the

malting and brewing industry through the Malting Barley Improvement

Association in the evaluation of potential malting barley varieties. Acceptable malting barley varieties are made known to growers through publications listing the varieties available for production or, in some states, the



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XII. Quality Testing Procedures Used to Develop Acceptable Malting Barley Varieties

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