G4-G6 Flashcards
is the scientific study of microorganisms, both in food and used to produce food. This includes microorganisms that contaminate food, as well as those used in microbial food and fermented products.
FOOD MICROBIOLOGY
-microalgae
-a good microbial source of vitamin B12
-source of beta carotene
CHLORELLA
-Fusarium venenatum
-mycoprotein; meat substitute
QUORN
-controlled microbial growth and enzymatic
conversions of food components.
FERMENTATION
ripened cheeses
- e.g. Camembert and Brie
- Penicillium camemberti
Surface mold
ripened cheeses
- e.g. Roquefort and Gorgonzola
- Penicillium roqueforti.
Internal mold
-Aspergillus oryzae
-rice or soybeans
-production of sake, soy sauce, and miso
Koji
-ingested live microorganisms that are beneficial to the humans
-no risk of harmful response to the host
-can be found in yogurt and other fermented foods, dietary
supplements, and beauty products.
PROBIOTICS
unacceptable changes in
flavor, odor, and other
organoleptic properties of food
FOOD SPOILAGE
ommon spoilage microorganism
✓ peptide chains broken down
✓ production of ammonia, H2S, indole, amine
Pseudomonas
- packed refrigerated meat
- “deep tissue” or “bone taint” spoilage
- Clostridium
Vacuum
✓ hydrolysis of polysaccharides to simple sugars
HIGH-CARBOHYDRATE FOOD
gummy and slimy polymer (dextran)
- Leuconostoc mesenteroides
Sucrose
- amylase production
- Bacillus subtilis in bread
Starch
✓ pectin
- responsible for structure of
fruits and vegetables
FRUITS & VEGETABLES
✓ due to under processing, inadequate
cooling, leakage, pre-process spoilage.
CANNED FOODS
- souring, cheesy, or butyric odors
- Thermoanaerobacterium thermosacchrolyticum
Thermophilic anaerobe spoilage
- putrid odors
- Clostridium putrefaciens
Putrefactive anaerobes
✓ molds can grow in acidic foods.
✓ cottony growth on the surface
FRUITS
→ Inherent to food
→ e.g. pH, moisture content,
nutrient content, OR potential,
antimicrobial constituents, &
biological structure.
Parameters that are inherent to the food
Intrinsic Parameters
→ storage environment
→ e.g. Temperature, RH,
Gases, other microorganisms.
are those that are not dependent to the food itself, but rather to the storage environment that affect both the foods and microorganisms.
Extrinsic Parameters
- use of multiple microbial stressors.
-e.r. limiting aw and lowering of pH. - different preservation techniques+ intrinsic parameters.
utilizes multiple microbial stressors that act by different mechanisms.
Hurdle Technology
any illness resulting from the spoilage of contaminated food by pathogenic bacteria, viruses or parasite that contaminate food, as well as prions (the agents of mad cow disease) and toxins such as aflatoxins in peanuts poisonous mushrooms, and various species of beans that have not been boiled for at least 10 minutes.
Foodbore Illness
-microorganims in food that cause diseases
- infection or intoxication
- caused by bacteria, fungi, viruses, parasites.
Food borne pathogens
-ingestion of food contaminated with pathogen
- invasion of tissue or production of toxin inside the host.
Food Borne Infection
-2,600 serovars of S. enterica
-Typhoidal - enteric fever
-Non-typhoidal - inflammation of stomach or intestine
-common cause of gastroenteritis
-C. jejuni & C. coli
-most common reservoir: poultry
SALMONELLA
-several pathotypes
-enteric or diarrheal disease, UTI, or sepsis/meningitis
-most common: STEC Shiga toxin
-most important: E. coli O157:H7
PATHOGENIC E. COLI
-monocytogenes meningitis, encephalitis, abortion, neonatal
infection, and septicemia
-dairy and ready-to-eat products
LISTERIA
-seafoods
-V. cholerae
-cholera
VIBRIO
-ingestion of bacteria production of toxin
e.g.,
-Vibrio cholerae - cholera toxin
-Entero-toxigenic E. coli - heat-stable & heat-labile toxins
-Clostridium perfringens - enterotoxin
Foodborne Toxicoinfection
-responsible for 95% of non- bacterial gastroenteritis
-ready-to-eat foods handled by infected food handlers
Norovirus
-inflammation of liver.
-Hepatitis A and E.
-under-cooked meat or meat products.
Viral Hepatitis
-ingestion of toxins produced by microorganisms.
-live microorganism does not have to be ingested.
Food borne intoxication
-Clostridium botulinum
-botulinum neurotoxin
-paralysis
BOTULISM
-emetic Bacillus cereus
-nausea and vomiting
-associated with fried rice
CEREULIDE INTOXICATION
-Food safety is a scientific discipline describing: Handling, Preparation, Storage, Serving of food in ways that prevents food borne illness
FOOD SAFETY
are best practices that give broad guidelines on techniques and protocols that should be used in the food supply chain to decrease germs.
GHP( Good Hygienic Practices)
branch of applied microbiology in which microorganisms are used for the production of important substances, such as antibiotics, food products, enzymes, amino acids, vaccines, and fine chemicals.
INDUSTRIAL MICROBIOLOGY
-technology that utilizes biological systems, living organisms or parts of this to develop or create different products.
BIOTECHNOLOGY
-The science of is called “zymology”
-an enzyme catalysed, metabolic process whereby organisms convert starch or sugar like glucose to alcohol or an acid anaerobically releasing energy.
FERMENTATION
a container which is maintained in an environment favorable to the operation of a desired biological process.
Fermenter (or fermentor)
-It is an upright closed cylindrical tank with at least four baffles, heating and/or cooling device, sparger for aeration, agitator with impellers, and inlets and/or outlets for organisms, media, and exhaust gases.
STIRRED TANK REACTORS (STRS)
are involved in growth,
development, and reproduction of the organism.
Primary metabolites
-Health behavior is an action taken by an individual to maintain, achieve, or regain good health and to prevent illness. It usually reflects an individual’s health beliefs.
HEALTH BEHAVIOR
-Health behavior is an action taken by an individual to maintain, achieve, or regain good health and to prevent illness. It usually reflects an individual’s health beliefs.
HEALTH BEHAVIOR
-Biopolymers are microbially produced polymers used to modify the flow characteristics of liquids and to serve as gelling agents.
BIOPOLYMERS
- are microbially produced polymers used to modify the flow characteristics of liquids and to serve as gelling agents.
Biopolymers
-synthesized near the end of the
exponential growth phase and during the
early stationary phase (idiophase)
Secondary Metabolites
is a peptide hormone produced by beta cells of the pancreatic islets encoded in humans by the INS gene.
Insulin
is a peptide hormone that stimulates growth, cell reproduction, and cell regeneration in humans and other animals.
Human growth factor
production concentrates on simple hydrolytic enzymes (proteases,
amylases, pectinases) that degrade natural polymers such as proteins,starches, or pectin.
Enzymes
used in sugar production form starch.
amylases
used by biscuit manufacturers to lower the
protein level of flour
proteases
used to predigest baby foods.
trypsin
used to clarify fruit juices and papain which is used to tenderize meat for cooking- used in sugar production form starch.
cellulases and pectinases
used to tenderize meat for cooking.
papain
also know as are rennin and used to manufacture cheese and used to hydrolyze protein.
chymosin
used to to enhance the ripening of the blue-mold cheese in the production of Roquefort cheese.
lipases
8.used to break down lactose to glucose and galactose.
lactases
DNA- cutting enzymes; recognize
and cut DNA only at a particular sequence of nucleotides.
Restriction enzymes
cloning vector; carries pieces of DNA.
Plasmid
enzyme that links together DNA strands with double stranded breaks.
DNA ligase
Transfer of DNA is brought about by the application
of pulsed field to the cells.
ELECTROPORATION
(short form for electric field- mediated membrane permeabilization) is a physical technique that is used to get DNA into organisms that are difficult or impossible to transform, especially cells that contain thick cell walls.
Electroporation
-a device for injecting cells with genetic information
-payload is an elemental particle of a heavy metal coated
with plasmid DNA
-often simply referred to as biolistics
-designed for plant transformation
- is often simply referred to as biolistics and is
designed for plant transformation.
GENE GUN
-process of using a very fine needle to insert substances at a microscopic or borderline macroscopic level into a single living cell.
-a simple mechanical process in which a needle roughly 0.5 to 5 micrometers in diameter penetrates the cell membrane and/or the nuclear envelope.
MICROINJECTION
-A genetically modified organism is any
organism whose genetic material has been
altered using genetic engineering techniques.
GENETICALLY MODIFIED ORGANISMS
is a plant pathogen that
causes tumor formation called crown gall disease.
Agrobacterium tumefaciens
- the study of the distribution and environmental relationships of microorganisms as well as their relationship with each other and to higher organisms.
Microbial Ecology
- interaction between populations existing in close association with each other
Symbiosis
- reflect some form of cooperation between species or
populations
Positive interactions
- when two or more populations inhabit the same living space and interact in a mutually beneficial manner
- reciprocal benefit
Mutualism
-A notable illustration of a facultative mutualistic relationship is the symbiosis between the ciliate Paramecium bursaria and members of the green algae Chlorella
Protozoa Endosymbionts
-Microorganisms that are mutualistic can defend the host from danger, provide vital nutrients, boost fitness, and facilitate interactions with other species.
Microorganism-Insect Mutualism
-A fungus and a photosynthetic bacteria or algae
live in symbiotic harmony. Inside the fungus are the algal or bacterial cells.
Fungi-Algae Mutualism
One of the most well-known examples of host-microbiome symbiosis
rumen environment
- a two- way positive exchange of materials
- beneficial complementary resources
- not obligatory
Cooperation
-a low specificity relationship which displays a one-way
positive exchange of materials.
-the commensal benefits while the host is neither harmed nor helped.
COMMENSALISM
refers to heterogeneous structures comprising different
populations of microorganisms surrounded by a matrix
(mostly of exopolysaccharides) that allows their attachment
to inert (e.g., rocks, glass, plastic) or organic (e.g., skin,
cuticle, mucosa) surfaces.
Biofilm
An organism is either damaged or
killed by a chemical secretion of another organism.
Antibiosis
a mutually negative interaction among two or more species (population) involved
Competition
-movement and conversion of materials by biochemical
-driven directly or indirectly by the radiant energy of the
sun or by the energy of reduced materials/minerals
-Energy is absorbed, converted, temporarily activities throughout the atmosphere, hydrosphere and lithosphere stored and eventually dissipated.
Nutrient/Biogeochemical Cycling
- determines the amount of CO2 in the
atmosphere as well as the rate of turnover
of organic matter - fairly complex for it includes all life on earth as well
as inorganic C reservoirs and the links between them
Carbon Cycle
-It is a biogeochemical process through which nitrogen is converted into many forms, consecutively passing from the atmosphere to the soil to organism and back into the
atmosphere.
-It involves several processes such as nitrogen fixation, assimilation, ammonification, nitrification, and denitrification.
NITROGEN CYCLE
-describes the movement of sulfur through the geosphere and biosphere.
Sulfur Cycle
are indicated by yellow arrows and reductions
by red arrows.
Oxidations
The Principle of Microbial Infallibility
“No natural organic compound is resistant to biodegradation provided that environmental conditions are favorable.”
Bioremeditation
transformation of every type
- reactions that yield more complex products than the starting material complete
- oxidation of organic compounds to CO2, H2O,NO3 and other inorganic components
Biodegradation
The activity of man which disturbs the balance of nature leading to the loss of information (Biodiversity) and loss of structure of the natural environment.
Pollution
consists of microorganism that improves the
nutrient content of the soil and enhances their availability to the crops.
Biofertilizers
