3
Chapter 1
History and Development
of Food Microbiology
introduction
Except for a few sterile foods, all foods harbor one or more types of microorganisms. Some of
them play desirable roles in food, such as in the production of naturally fermented foods, whereas
others cause food spoilage and foodborne diseases. To study the role of microorganisms in food
and to control them when necessary, it is important to isolate them in pure culture and study their
morphological, physiological, biochemical, and genetic characteristics. Some of the simplest techniques in use today for these studies were developed over the past 300 years; a brief description is
included here.
Discovery of Microorganisms
The discovery of microorganisms 1–3 ran parallel with the invention and improvement of the
microscope. Around 1658, Athanasius Kircher reported that, using a microscope, he had seen
minute living worms in putrid meat and milk. The magnification power of his microscope was
so low that he could not have seen bacteria. In 1664, Robert Hooke described the structure of
molds. However, probably the first person to see different types of microorganisms, especially
bacteria, under a microscope that probably did not have a magnification power above 300×, was
Antony van Leeuwenhoek. He observed bacteria in saliva, rainwater, vinegar, and other materials; sketched the three morphological groups (spheroids or cocci, cylindrical rods or bacilli, and
spiral or spirilla); and also described some as being motile. He called them animalcules, and
between 1676 and 1683, he reported his observations to the newly formed leading scientific
organization, The Royal Society of London, where his observations were read with fascination.
As reasonably good microscopes were not easily available at the time, other interested individuals and scientists during the next 100 years only confirmed Leeuwenhoek’s observations. In the
19th century, as an outcome of the Industrial Revolution, improved microscopes became more
Chapter 1
History and Development
of Food Microbiology
introduction
Except for a few sterile foods, all foods harbor one or more types of microorganisms. Some of
them play desirable roles in food, such as in the production of naturally fermented foods, whereas
others cause food spoilage and foodborne diseases. To study the role of microorganisms in food
and to control them when necessary, it is important to isolate them in pure culture and study their
morphological, physiological, biochemical, and genetic characteristics. Some of the simplest techniques in use today for these studies were developed over the past 300 years; a brief description is
included here.
Discovery of Microorganisms
The discovery of microorganisms 1–3 ran parallel with the invention and improvement of the
microscope. Around 1658, Athanasius Kircher reported that, using a microscope, he had seen
minute living worms in putrid meat and milk. The magnification power of his microscope was
so low that he could not have seen bacteria. In 1664, Robert Hooke described the structure of
molds. However, probably the first person to see different types of microorganisms, especially
bacteria, under a microscope that probably did not have a magnification power above 300×, was
Antony van Leeuwenhoek. He observed bacteria in saliva, rainwater, vinegar, and other materials; sketched the three morphological groups (spheroids or cocci, cylindrical rods or bacilli, and
spiral or spirilla); and also described some as being motile. He called them animalcules, and
between 1676 and 1683, he reported his observations to the newly formed leading scientific
organization, The Royal Society of London, where his observations were read with fascination.
As reasonably good microscopes were not easily available at the time, other interested individuals and scientists during the next 100 years only confirmed Leeuwenhoek’s observations. In the
19th century, as an outcome of the Industrial Revolution, improved microscopes became more