microorganism
Quick Summary
Microbiology is the study of microorganisms, which are diverse, generally minute, and simple life forms. This field encompasses bacteria, archaea, algae, fungi, protozoa, and viruses. The discovery of these invisible life forms in the 17th century was a significant scientific milestone, as it was theorized that unseen entities caused decay and disease.1
Microorganisms are integral to daily life, found in the human body, soil, seas, and air. They play crucial roles in decomposition, nutrient recycling, and processes like fermentation for food and beverages. They are also vital for ecological balance, breaking down organic matter and making it available for other organisms.1
Bacteria, a major group of microorganisms, are prokaryotes, meaning they lack a distinct nucleus. They are found in nearly every environment on Earth and are essential to many ecological processes, including nutrient cycles like nitrogen fixation. Viruses, while on the borderline of living organisms, are also studied in microbiology and are obligate parasites that depend on host cells for replication.2345
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dairy productInoculation 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…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…
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cheese makingInoculation and curdling…is then inoculated with fermenting microorganisms and rennet, which promote curdling.
Read More…is then inoculated with fermenting microorganisms and rennet, which promote curdling.
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- food preservationMicrobial 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…
Read More…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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bakingSpoilage by microbesBakery 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,…
Read MoreBakery 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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eggMicrobiologyMore 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…
Read MoreMore 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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fish processingMicrobiologyBecause 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.
Read MoreBecause 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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fruit processingStorage concernsMicroorganisms 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…
Read MoreMicroorganisms 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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meat processingMeat microbiology, safety, and storage…of a living immune system, microorganisms are unchecked in their ability to grow and reproduce on meat surfaces.
Read More…of a living immune system, microorganisms are unchecked in their ability to grow and reproduce on meat surfaces.
Read More- poultry processingMicrobial 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.
Read More…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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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).
Read More…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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human diseaseRickettsial 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…
Read More…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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