FRIENDLY MICROBIES: BREAD

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FRIENDLY MICROBIES BREAD
What were the first loaves of bread like? Grains
of wheat were ground using only stones and the
sieve would not be invented for a very long time
to come. The dough was not left to rise either
this was unheard of at the time. The result of
all this was a type of very hard flat biscuit
that was definitely difficult to chew. Of course,
primitive man did have an enormous mouth. It was
only after fire was discovered and tools invented
that the muscles of the mouth did not have to
work so hard. In fact, the human mouth went
through a major transformation over thousands and
thousands of years and, today, is much much
smaller than the mouths of our first ancestors
(which is why our wisdom teeth usually give us so
much trouble). It is believed that it was the
Egyptians (around 2600 years before Christ) who
began to make bread using a more similar process
to the current one leavened with added salt and
baked in an oven. But why did people start to
leaven bread? As far as we know, like most other
discoveries, it was an accident. Somebody had
accidentally left dough in the open air from one
day to the next. And surprise, surprise! The
following day, the dough had risen to twice its
size. Now this is where audacity came in the
same someone actually dared to put it in the
oven. No pain, no gain as the saying goes - in
this case, the bread turned out to be much
softer, tastier and crustier a real treat! And
of course, this person continued to make bread
the same way for the rest of her life - her, her
relatives, friends, neighbours and so on. Of
course they never understood the reason for this
phenomenon this was only unravelled about a
century ago when French scientist Louis Pasteur
discovered that a microbe was responsible for the
entire process. A microbe? I hear you ask. Yes, a
microbe! Microbes are really tiny beings so tiny
that we can only see them with the aid of a
microscope. Hence the name micro very small
and bio life.   You might not know this but
with microbes, just like with people, there are
the bad guys, which cause discomfort, spread
disease and destroy our food, the truly useful
guys, and the absolutely fantastic guys, without
which life would not even be possible. This may
seem like an exaggeration, but it is not.   The
microbe which causes the dough to rise is one of
the very useful microbes. It is a yeast, hence
the name yeast bread. The yeast reacts with some
of the components of the flour (sugars) and
slowly releases a gas carbon dioxide and an
alcohol ethanol as well as other substances
which give the bread its taste and a smell that
makes your mouth water. It is the gas that is
produced (carbon dioxide) that causes the dough
to rise. If the dough is made with wheat flour,
it is capable of holding this gas and slowly
increases in size. Cornbread, on the other
hand, which is made only with corn flour, remains
flat, dense and dry - very different from wheat
bread.
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MICRÓBIOS AMIGOS (cont.)
Try this experimentGet a little yeast from the
bakery or some dried packet yeast, which is
usually sold in the desserts section of most
supermarkets. Mix one cup of flour with lukewarm
water and add one level coffee spoon of yeast (it
may not seem much but I can assure you there are
millions of cells in it). Cover the bowl with a
cloth and let the mixture rest for about an hour.
Take a look at what is happening every 20 minutes
or so. Watch and see as they say. Even better,
watch and measure the height of the dough with a
ruler and keep a record of the different
measurements. Maybe you have made bread before,
but this time you will be amazed at the hard work
done by an organism as microscopic as bakers
yeast.   Have you ever noticed the ingredients of
bread sold in the supermarkets? Sometimes it says
that it is made of wheat flour type 45, or 65,
80, 110, etc. What does this mean? Well, for now,
it means that the higher the figure, the less
white the soft part of the bread will be.
  After the grains of wheat have been ground,
they are passed through a sieve. This can be done
using only the inner part of the wheat grain to
make the flour and we get a really white flour
or we can make a fairly brown flour, which
includes the outer layers of the grain.   The
numbers on the packet are related to the amount
of bran in the flour. For example, type 150 flour
has a much higher bran content than a type 45
flour.   There are those of us who think that
bread is fattening. One things for sure it is
one of the most important ingredients in our food
supply and is even better if it is a little
browner, that is, if it has more bran (more
fibre). What is devastatingly fattening is the
butter we so generously spread on our bread and
the ham, the cheese and the other things we put
on our sandwiches. It is the fillings that make
us fat. Just as a matter of interest, did you
know that the word sandwich originated from the
name of an English earl the Earl of Sandwich
(1718-1792), whose name was John Montague, and
who began to eat meat and other things between
two slices of bread in order to be able to play
cards without stopping to eat (he was so
addicted). It had the advantages of not having to
dirty his hands or get up.   But sandwiches have
other benefits too. It is a quick food which
means we dont have to spend a lot of time
eating. But this isnt usually because we want to
have more time to play cards. If only!E, por
último, sabia que a palavra companheiro (do latim
cum panis) vem dos tempos em que cada
pessoa, à mesa, partilhava o seu naco de pão com
o vizinho do lado? Ou seja, um bom amigo era
aquele com quem partilhávamos o pão. Outros
tempos! Maria Margarida Guerreiro
Cross section of a grain of wheat
Bran Endosperm Germ