Biomedical Engineering Reference
In-Depth Information
the hypothesis of a precise symbolism between the idea of elaborate and stylish, and
that of sourdough. Fermentation and leavening makes bread something different
from the raw cereals, i.e. an artifact, in the sense of “made art”. Besides symbolism,
sourdough bread has acquired a central social position over time. Bread, and espe-
cially sourdough bread, has become central in the diet of peasant societies. This
suggests that the rural population empirically perceived sensory and nutritional
transformations, which are also implemented through sourdough fermentation. In
other words, the eating of bread, and especially of sourdough bread, was often a
choice of civilization.
The oldest leavened and acidified bread is over 5,000 years old and was discovered
in an excavation in Switzerland [
2
] . The fi rst documented production and consumption
of sourdough bread can be traced back to the second millennium B.C. [
3
] . Egyptians
discovered that a mixture of flour and water, left for a bit of time to ferment, increased
in volume and, after baking along with other fresh dough, it produced soft and light
breads. Much later, microscopic observations of yeast as well as measurements of
the acidity of bread from early Egypt demonstrate that the fermentation of bread
dough involved yeasts and lactic acid bacteria - the leavening of dough with sour-
dough had been discovered [
4
]. Eventually, the environmental contamination of
dough was deliberately carried out by starting the fermentation with material from
the previous fermentation process. Egyptians also made use of the foam of beer for
bread making. At the same time, Egyptians also selected the best variety of wheat
flour, adopted innovative tools for making bread, and used high-temperature ovens.
The Jewish people learned the art of baking in Egypt. As the Bible says, the Jews
fleeing Egypt took with them unleavened dough.
In Greece, bread was a food solely for consumption in wealthy homes. Its prepa-
ration was reserved for women. Only in a later period, does the literature mention
evidence of bakers, perhaps meeting in corporations, which prepared the bread for
retail sale. The use of sourdough was adopted from Egypt about 800 B.C. [
4
] . Greek
gastronomy had over 70 varieties of breads, including sweet and savoury types,
those made with grains, and different preparation processes. The Greeks used to
make votive offerings with flour, cereal grains or toasted breads and cakes mixed
with oil and wine. For instance, during the rites dedicated to Dionysus, the god of
fertility, but also of euphoria and unbridled passion, the priestesses offered large
loaves of bread. The step from the use of sacrificial bread to the use of curative
bread was quick. Patients, who visited temples dedicated to Asclepius (the god of
medicine and healing), left breads, and, upon leaving the holy place, received a part
of the breads back imbued with the healing power attributed to the god [
5,
6
] .
The use of sourdough is also part of the history of North America. The use of
sourdough as a leavening agent was essential whenever pioneers or gold prospectors
left behind the infrastructure that would provide alternative means of dough leavening.
Examples include the Oregon Trail of 1848, the California gold rush of 1849, and
the Klondike gold rush in the Yukon Territories, Canada, in 1898. During the 1849
gold rush, San Francisco was invaded by tens of thousands of men and women in
the grip of gold fever. Following the gold rush, sourdough bread remained an ele-
ment that distinguishes the local tradition until today. Some bakeries in San Francisco
claim to use sourdough that has been propagated for over 150 years. The predominant
