Effect of the Malting Barley Variety (Hordeum vulgare L.) on Fermentability1
Joerg
Gunkel,2,4
Michael
Voetz3
and
Frank
Rath3
1A
portion
of
these
results
have
been
communicated
at
the
87th
Oktobertagung
of
the
Versuchs-
und
Lehranstalt
fuer
Brauerei
in
Berlin
(10th
October
2000)
and
at
the
EBC
28th
International
Congress
in
Budapest
(Poster
PO2).
2Present
address:
GlobalMalt
GmbH
&
Co.
KG,
Ludwig-Schwamb-Strasse
9-11,
D-67574
Osthofen;
gk@schill-malz.de
3Research
and
Teaching
Institute
for
Brewing
in
Berlin
(VLB),
Seestrasse
13,
D-13353
Berlin,
Germany;
fir@vlb-berlin.org
4Corresponding
author.
E-mail:
gk@schill-malz.de
J. Inst. Brew. 108(3), 355-361, 2002 | VIEW ARTICLE
ABSTRACT
The
influence
of
the
malting
barley
genotype
on
the
apparent
attenuation
limit
(AAL)
was
investigated.
The
AAL
level
correlated
closely
with
the
maltose
concentration
in
the
wort
but
was
not
affected
by
other
fermentable
sugars
or
by
the
total
carbohydrate
content.
The
chemical
composition,
modification,
amylolytic
enzyme
activities
and
several
starch
properties
of
selected
malts
were
studied
in
detail.
Variations
in
the
maltose
concentration
could
almost
solely
be
traced
back
to
genotype-dependent
disparities
of
β-amylase
thermostability.
These
differences
are
due
to
interallelic
polymorphisms
of
the
β-amylase
gene
and
are
easily
detected
by
PCR.
Hence,
PCR
primers
offer
remarkable
prospects
for
breeding
barley
on
the
basis
of
a
marker-assisted
selection
(MAS).
Key words:
Apparent attenuation limit, β-amylase, β-amylase thermostability, barley breeding, carbohydrates, fermentability, maltose.
Publication no. G-2002-0826-076 ©2002 The Institute & Guild of Brewing