Enzymes, Extracts, Other Session
Kevin S Redd, School of Plant Science, University of Tasmania, Private Bag 55, Hobart, TAS 7001, Australia
Co-author(s): Evan Evans and Anthony Koutoulis, School of Plant
Science, University of Tasmania, Hobart, Australia; Gordon MacAulay,
GrainGrowers Australia, North Ryde, Australia; Elvig Niels, Novozymes
A/S, Bagsvaerd, Denmark
ABSTRACT: Malting, mashing, fermentation, and maturation
are enzymatic processes. Barley, the main raw material, contains extract
components such as starches and proteins, as well as enzymes such as
amylases and proteases. As malted barley is a relatively expensive raw
material and the enzymes produced by malting have become commercially
available on a large scale, brewers have taken an interest in developing
methods to substitute the malt with unmalted raw materials by using
these exogenous enzymes. It is already common practice to use 25–50%
unmalted cereals (adjunct) in conjunction with malt, and therefore the
idea grew to substitute an even higher proportion of the malt with
unmalted raw barley by processing the adjunct with exogenous enzymes.
Brewing good quality beer directly and entirely from barley is now a
practical reality with the development of Novozymes Ondea Pro® enzyme
technology. We outline the results from a pilot barley brewing trial
using the Novozyme Ondea Pro® enzyme technology and provide the
fermentability and process efficiency data for a range of
Australian-grown barley grains from different varieties, geographic
locations, and growing conditions. We used a small scale laboratory test
to demonstrate that Ondea Pro® barley brewing is very efficient and
comparable to malt-based brewing. The current malting varieties and
Hindmarsh (a food variety) appear to be the most suitable for barley
brewing as there is at least a 3% extract advantage with such varieties.
The barley varieties associated with improved levels of extract and
fermentability include “high” fermentability Flagship; “intermediate”
fermentability Hindmarsh, Buloke, and Commander; and “low”
fermentability Fitzroy, Schooner, Gairdner, and Baudin. We emphasize
that good quality barley is required for optimal barley brewing results
and recommend that the purchase of cheaper feed grade barley for barley
brewing will result in less consistent brewing outcomes in terms of
efficiency (extract, lautering, filterability, fermentability) and beer
quality. In addition, cheaper feed grade barley will reduce the
opportunities to optimize the use of the Ondea Pro® enzyme product,
therefore costing brewers substantially more in the long term.
Optimization of the use of Ondea Pro® during mashing has considerable
potential to further reduce the cost of barley brewing. In addition to
the laboratory results, we provide economic modeling to illustrate a
scientific and economic assessment of the potential benefit from the use
of enzymes on different Australian barley varieties, with a focus on
the gains to be made in emerging markets.
Kevin Redd received a
bachelor’s degree in biology from the University of California, Santa
Cruz, and then began a series of assignments in Alaska and British
Columbia for the National Marine Fisheries Service and International
Pacific Halibut Commission. He moved to Australia to undertake a Ph.D.
program in forensic molecular ecology at the University of Tasmania
before commencing work on a range of GRDC-funded malt- and
barley-related projects.
