microorganism
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Assorted References
- cheese making
- In dairy product: Inoculation and curdling
…is then inoculated with fermenting microorganisms and usually with rennet, which promote curdling. The fermenting microorganisms carry out the anaerobic conversion of lactose to lactic acid. The type of organisms used depends on the variety of cheese and on the production process. Rennet is an enzymatic preparation that contains a…
Read More - In cheese making: Inoculation and curdling
…is then inoculated with fermenting microorganisms and rennet, which promote curdling.
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- In dairy product: Inoculation and curdling
- effect on xenobiotic compounds
- In soil: Pathways of detoxification
Soil microorganisms, particularly bacteria, have developed diverse means to use readily available substances as sources of carbon or energy. Microorganisms obtain their energy by transferring electrons biochemically from organic matter (or from certain inorganic compounds) to electron acceptors such as oxygen (O2) and other inorganic compounds.…
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- In soil: Pathways of detoxification
- microbiology
- In microbiology
The word microbe was coined in the last quarter of the 19th century to describe these organisms, all of which were thought to be related. As microbiology eventually developed into a specialized science, it was found that microbes are a very large group of extremely diverse organisms.
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- In microbiology
- occurrence in hot springs
- In hot spring
…are caused by thermophilic (heat-loving) microorganisms, which include certain types of bacteria, such as cyanobacteria, and species of archaea and algae. Many thermophilic organisms grow in huge colonies called mats that form the colourful scums and slimes on the sides of hot springs. The microorganisms that grow in hot springs…
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- In hot spring
- osteomyelitis
- In bone disease: Infectious diseases of bone
…infection of bone tissue by microorganisms, which may gain access to bone either by spreading in the bloodstream in an infectious lesion elsewhere in the body (hematogenous osteomyelitis) or through a skin wound such as an open fracture.
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- In bone disease: Infectious diseases of bone
- plankton
- In marine ecosystem: Plankton
…range in size from tiny microbes (1 micrometre [0.000039 inch] or less) to jellyfish whose gelatinous bell can reach up to 2 metres in width and whose tentacles can extend over 15 metres. However, most planktonic organisms, called plankters, are less than 1 millimetre (0.039 inch) long. These microbes thrive…
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- In marine ecosystem: Plankton
- water quality and treatment
- In wastewater treatment: Removal of plant nutrients
…first converted into nitrates by microorganisms. The nitrates are further metabolized by another species of bacteria, forming nitrogen gas that escapes into the air. This process requires the construction of more aeration and settling tanks and significantly increases the cost of treatment.
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- In wastewater treatment: Removal of plant nutrients
- water supply systems
- In water supply system: Health concerns
The most important microbiological measure of drinking-water quality is a group of bacteria called coliforms. Coliform bacteria normally are not pathogenic, but they are always present in the intestinal tract of humans and are excreted in very large numbers with human waste. Water contaminated with human waste always…
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- In water supply system: Health concerns
food spoilage
- In food preservation: Microbial contamination
…are the principal types of microorganisms that cause food spoilage and food-borne illnesses. Foods may be contaminated by microorganisms at any time during harvest, storage, processing, distribution, handling, or preparation. The primary sources of microbial contamination are soil, air, animal feed, animal hides and intestines, plant surfaces, sewage, and food…
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- baked goods
- In baking: Spoilage by microbes
Bakery products are subject to the microbiological spoilage problems affecting other foods. If moisture content is kept below 12 to 14 percent (depending on the composition), growth of yeast, bacteria, and molds is completely inhibited. Nearly all crackers and cookies fall below this level,…
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- In baking: Spoilage by microbes
- eggs
- In egg: Microbiology
More than 90 percent of all eggs are free of contamination at the time they are laid; contamination with Salmonella bacteria and with certain spoilage organisms occurs essentially afterward. Proper washing and sanitizing of eggs eliminates most Salmonella and spoilage organisms deposited on the…
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- In egg: Microbiology
- fish
- In fish processing: Microbiology
Because of their soft tissues and aquatic environment, fish are extremely susceptible to microbial contamination. At the time of harvest, fish carry a high microbial load on the surface of their skin, in their intestinal tract, and in their gills.
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- In fish processing: Microbiology
- fruits
- In fruit processing: Storage concerns
Microorganisms can also cause problems during senescence and storage. Many bacteria and fungi, for instance, are involved in decay after harvest. Typical fungi include Alternaria, Botrytis, Monilinia, Penicillium, and Rhizopus. These fungi are generally weak pathogens, in that they usually invest only weak or damaged…
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- In fruit processing: Storage concerns
- meats
- In meat processing: Meat microbiology, safety, and storage
…of a living immune system, microorganisms are unchecked in their ability to grow and reproduce on meat surfaces.
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- In meat processing: Meat microbiology, safety, and storage
- poultry
- In poultry processing: Microbial contamination
…medium for the growth of microorganisms. The principal spoilage bacteria found on poultry include Pseudomonas, Staphylococcus, Micrococcus, Acinetobacter, and Moraxella. In addition, poultry often supports the growth of certain pathogenic (disease-causing) bacteria, such as Salmonella.
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- In poultry processing: Microbial contamination
role in
- infectious diseases
- In infectious disease
…agent, often a type of microorganism, that impairs a person’s health. In many cases, infectious disease can be spread from person to person, either directly (e.g., via skin contact) or indirectly (e.g., via contaminated food or water).
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- In infectious disease
- rickettsial diseases
- In human disease: Rickettsial diseases
…rickettsial diseases are caused by microorganisms that fall between viruses and bacteria in size. These minute agents are barely visible under the ordinary light microscope. Like viruses, they multiply only within the cells of susceptible hosts. They are found in nature in a variety of ticks and lice and, when…
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- In human disease: Rickettsial diseases