Barley presents a unique case since it is the main cereal subjected to the steeping and
germination post harvest process to breakdown the endosperm and generate the essential
enzymes required for further hydrolysis of starch during mashing. This gentle natural process
necessitates rising of the moisture content providing a conducive environment for microbial
proliferation (Gudmestad et al., 2000). Any attempt to chemically control fungal growth also
interferes with the barley physiological and biochemical processes hence reduced malt
quality. It also raises concern over mycotoxin residues in the beer. In addition various fungal
metabolites are also phytotoxic to the seed and inhibit or retard germination depending on the
concentration and hence preventing the optimal modification of the malt (Flannigan, 1996).
Presence of Fusarium in barley has also been associated with ‘gushing’ (uncontrolled
foaming) of beer (Parry et al., 1995, Gudmestad et al., 2000). Therefore, barley destined for
malting has to be of optimum microbial quality.