Microorganisms – their presence and their meanings
The microorganisms are the smallest living beings, often invisible to the naked eye. They are everywhere: in water, earth, air, in or on living or dead organisms, etc. Most of them are very useful, e.g .:
- Humus consisting of microorganisms is a valuable nutrient for plants.
- In water, microorganisms transform waste into essential substances;
- Human digestion and animal needs a variety of bacteria.
- Food and consumer products, and many remedies are generated by microbial metabolic actions (eg. Cheese, yogurt, bread, wine, vinegar, antibiotics).
Among the wide variety of microbes, most organisms are harmless to our health. A small portion of these microorganisms can cause disease yet. Then called pathogens. When these pathogens trigger a disease called the infection process. If pathogenic microorganisms grow on foods or objects, we call this contamination.
Different varieties of microorganisms
The microorganisms are divided into 4 groups:
- Bacteria (e.g salmonella, coli bacteria, staphylococcus)
- Fungi (e.g yeasts and molds)
- Parasites (e.g amoeba, tapeworm)
- Viruses (e.g influenza virus, Noro virus)
Their size varies from smaller virus (approx. One-hundredth to one thousandth of a millimeter) to interference (approx. 1 mm). Given that microbial contamination is not desirable and / or
can be harmful to products, we specifically sought these microorganisms that indicate some form of contamination of food or places that were tested. The presence of enteric bacteria (coli bacteria) indicates fecal soiling and therefore includes also the possible risks, namely the presence of pathogenic intestinal bacteria, viruses or parasites.
Bacteria or fungi that report such risks or deficiencies in hygiene are called indicator organisms.
In food hygiene and the environment, the main indicators are:
- all bacteria and all fungi, also named “TVC”
- intestinal bacteria called Escherichia coli (E. coli)
- yeasts and molds
Influence of external factors on microorganisms
The presence or growth of microorganisms are influenced by three factors:
- The personal hygiene and individual hygienic behavior (eg hand hygiene, clean clothes, behavior in case of illness).
- Hygienic handling of food (p. Ex. Clean zone / area unsuitable / wet / dry zone area, temperature, storage, preservation, separation of raw and cooked foods).
- Hygiene of premises, cleaning and disinfection (eg waiting rooms, consulting rooms, cafeteria, wetlands etc.)
Influence of temperature
In nature and as part of the natural cycle, the microorganisms are present in a more or less marked on most foods. They cover their nutritional needs through these well exploitable sources of carbon and nitrogen. In addition to chemical and physical influences, temperature is the main external factor influencing life, survival and proliferation of microbes.
The cold does not usually destroys microorganisms, it brakes at the most proliferation.After thawing or warming, the growth continues, and with it, the proliferation.
Moderate heat promotes the growth of microbes. Is between 20 ° C and + 40 ° C that most microorganisms reproduce quickly. Under optimal conditions, the number of Escherichia coli (E. coli) doubles every 20 minutes. A simple calculation shows that in this way, more than 16 million of coli bacteria can be produced by a single E. coli bacteria in the space of 8 hours.
The intense heat
From approx. + 62 ° C, ie, pasteurization, cooking, roasting, baking, etc. most of the bacteria are inactivated and destroyed. Some kinds of spores can survive this, however, heat treatment and is permanently eliminated more than 134 ° C.