and after tasting British ale in the 4th century the Emperor Julian was
compelled to pen a little poem:
Who made you and from what
By the true Bacchus I know you not
He smells of nectar
But you smell of goat.Clearly the unhopped ale of the time was not to his taste, but even
today beer enjoys an inferior reputation to that of wine.
Barley is the principal cereal used in the production of beer, although
other cereals are occasionally used and wheat beers such as Berliner
Weisse and the Gueuze–Lambic beers of Belgium are notable exceptions.
Africa has a number of traditional beers produced from local cereals
such as sorghum or millet and some of these are produced on a
substantial industrial scale. These however are the result of a mixed
lactic/ethanolic fermentation and bear little resemblance to European-
style beers.
One reason for barley’s pre-eminence is that the grain retains the
husk which affords protection during storage and transport and also
acts as an aid to filtration during wort separation. The gelatinization
temperature of malted barley starch is also low relative to that of other
cereals (52–59 1 C) and this enables the starch to be gelatinized (solubili-
zed), prior to enzymic digestion, at temperatures which will not inac-
tivate the starch degrading enzymea-amylase. A further advantage is
the presence in barley of substantial quantities of a second enzyme,
b-amylase, which is essential for the rapid conversion of starch and
dextrins to maltose.
Since the brewing yeast,Saccharomyces cerevisiae, is unable to fer-
ment starch, the first stage in the production of any alcoholic beverage
from starchy materials is conversion of the starch into fermentable
sugars. Human ingenuity has come up with a number of ways of doing
this. In the Oriental Technique, exemplified by products such assake,
mould enzyme preparations likekoji are used, whereas the prevalent
Western technique uses endogenous starch-degrading enzymes produced
in the grain through the process of malting. A third technique used in
some native cultures in South America is to use salivary amylase by
chewing the substrate so that it becomes coated with saliva and then
spitting it out to saccharify and ferment. This approach is not amenable
to industrialization and is not, as far as we are aware, the basis of any
large-scale commercial production of alcoholic beverages.
In malting, the grain is moistened by steeping in water and is then
spread on to a malting floor and allowed to germinate. During germi-
nation, hydrolytic enzymes, produced in the aleurone layer surrounding
the grain endosperm, attack the endosperm, mobilizing the nutrient and
Chapter 9 349