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The word 'biotechnology' is
modern, but humans have been
using biotechnology to
produce some of their staple
foods and favourite
beverages since the dawn of
civilisation. In early
farming communities in the
Middle East 10 000 years
ago, people ate bread for
sustenance, and drank beer
made by fermenting malted
grain or barley bread
steeped in water — with a
little help from invisible
friends. Baker’s yeast still
creates the bubbles that
cause bread dough to rise;
and brewer’s yeast puts the
fizz into beer. Early
civilisations quaffed wine
made from grape juice
fermented spontaneously, by
yeast and bacteria that form
the waxy bloom on ripe
grapes.
They preserved perishable
foods like fruit and
vegetables by pickling
them and made sausages by
fermenting raw meat mixed
with spice preservatives, as
salami is made today.
Nomadic herdsmen in central
Asia still rely on the same
staple diet of cheese and
yoghurt that sustained their
ancestors thousands of years
ago. Both are products of an
ancient biotechnological
practice that probably
pre-dates agriculture.
When milk is stored in
primitive vessels made from
goats’ or calves’ stomachs,
it curdles in the presence
of the digestive enzyme,
rennet. Lactococcus and
lactobacillus bacteria then
take over, transforming the
curd into cheese. Whole milk
fermented by Lactobacillus
yields another dietary
staple – yogurt. In ancient
times, the processes that
transformed simple raw
materials into tasty,
nutritious foods must have
seemed magical. We now know
the answer was
biotechnology, in the form
of friendly, fermenting
microbes.
Modern science
Biotechnology harnesses
the special biochemical
talents of living cells,
from simple, single-celled
bacteria and yeasts, to
complex multicellular
organisms like plants and
animals, for human benefit.
Agriculture itself can be
regarded as a form of
biotechnology – over
thousands of years, humans
have chosen animals and
plants from the wild and
gradually transformed them
into today’s familiar,
highly productive crops and
farm animals by selecting
types with useful qualities.
During the past century,
biotechnology has changed
from an art into a modern
science. To the small list
of microbes used by our
ancestors to make their
food, scientists have added
thousands of new species and
many more await discovery.
Over 3.5 billion years of
evolution, microbes have
acquired a vast repertoire
of biochemical skills that
allow them to colonise most
environments on land, in the
oceans, even the deep rocks
of the Earth’s crust. We are
just beginning to appreciate
their extraordinary
capabilities and use them
for our own needs and for
the benefit of the
environment.
Today, biotechnology is
indispensable to our health
and wellbeing. Every society
on earth uses and depends on
it in one form or another. |
