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What temperature do leftover foods need to be reheated?

165°F

What are two types of enzymatic spoilage caused by Pseudomonas fluorescens refrigerated foods?

proteolysis and lipolysis

Name a halophilic food infectious bacteria

Except for V. cholerae and V. mimicus, all Vibrio species are halophilic (salt requiring) Example: Vibrio parahaemolyticus

Botrytis cinerea is a mold found on grapes. What 2 wines styles require botrytis during growing or processing?

Sauternes and Tokaji

What is one of the molds that produces aflatoxin?

aspergillus flavus and aspergillus parasiticus

Name food borne pathogen that grows below 10 C.

Listeria Monocytogenes

What foodborne parasites is also commonly found in used cat litter?

Answer: toxoplasma gondii

What food-borne parasite can be found in hogs eating uncooked food waste?

Trichinella Spiralis

What type of microorganisms can grow in oxygen but prefer to grow in oxygen reduced environments?

Microaerophilic

Describe tyndallization.

intermittent boiling of spores for 1 hour each for 4 times to kill the spore.

What does LD50 mean?

The average amount of a drug, toxin, chemical substance/mixture or microorganism capable of killing 1/2 of the test animals exposed under specific test conditions. Median lethal dose (LD50) is commonly expressed in mg/kg, by oral intake or skin exposure.

Name 3 foods that are sources of Listeria.

Soft cheese made from unpasteurized milk, hot dogs, ready to eat deli meats, refrigerate spates or meat spreads, unpasteurized milk, refrigerated smoked seafood, raw sprouts

Extremophilic microbes are found in various environments. Name the extreme conditions associate with each types of microbes: Barophile; Halophile; Thermophile

Barophile: High pressure; Halophile - High Salt content; Thermophile: High heat/temperatures

Name 3 food poisoning microorganisms present in seafood.

vibrio cholerae, vibrio parahaemolyticus, vibrio vulnificus, yersinia ruckeri, aeromonas hydrophila, etc

How many seconds should you wash your hands as stated by the CDC?

20 seconds in the US and 15 in Canada

Steam table disease is caused by consumption of meat dishes adequately cooked but held at 50-55 degrees C for several hours. the causative agent is _____________.

Clostridium perfringens

What is the difference between commercial sterilization and pasteurization?

sterilization: processed at temps higher than 100 C, mainly for canning (retorting), destroys all microbes that may cause spoilage (may contain heat resistant bacteria spores such as endospores or thermophiles or flat sour bacteria), shelf life of 2+ years at room temperature, pasteurization: processed at temps lover than 100 C, typically high temperature for short time (HTST), destroys pathogenic microbes, reduces spoilage microbes, inactivates enzymes

What element in commerical apple juice can be fatal in large amounts?

arsenic

Rank the following in order of their tolerance to low water activity (highest resistance to least): yeasts, bacteria, molds

molds, yeasts, bacteria

Name 2 food born pathogens that can grow at refrigerator temperatures.

Yersinia enterocolitican, aeromonas hydrophilia, listeria monocytogenes

Define whether these are found in prokaryotic or eukaryotic cells: true nucles, circular DNA, unicellularity, no membrane-bound organelles, size of 10-100 micrometers

eukaryotic: nucleus, size ; prokaryotic: circular DNA, unicelluar, no membrane-bound organelles

What is an anaerobic bacteria?

a bacteria that does not require oxygen for growth

Name extrinsic factor in foods which affect microbial growth.

Environmental conditions where the food is stored

What are the 7 principles of HACCP?

1. conduct a hazard analysis 2. identify critcal control points(CCPs) 3. establish critical limits 4. establish monitoring procedes 5. establish corrective actions 6. establish verification procedures 7. establish record-keeping procedures

What value is the time required to have 1 log reduction in microorganisms or spores in a sample at a specific temperature?

D-value

What is the most commonly occurring food allergy in infants and young children?

Cow's milk

What is the F Value in microbial death kinetics?

Lethality - the time in minutes required to bring about a required log reduction in target microbial population at a defined temperature.

Name a class 2b carcinogen found in corn.

fumonisin

listeria monocytogenes

most dangerous for pregnant women, not allowed in RTE products

Name the genus of bacteria added with the starter culture for Swiss cheese.

Propionibacterium freudenreichii subspecies shermanii

What is a food intoxication?

An intoxication results when a person eats food containing toxins that cause illness

Clostridium botulinum growth can be inhibited under what pH?

4.6

Name two conditions under which yeasts and molds will outcompete most bacteria.

low Aw (0.6-0.7) and pH <4 or >9

What time and temperature combo for food service operators to safely cool cooked foods?

7°C in 2 hours, 41°C in 4 hours

What are five mycotoxins, and what is one food each is commonly found in?

aflatoxin- (peanuts, tree nuts, corn), patulin- (apples), roquefortine c (blue cheeses), ochratoxin a (grain, pork, coffee, wine grapes), citrinin (grains)

Lack of proper handwashing is commonly associated with what?

Shigella

Define food infection.

ingestion of organism which then produces toxin or infects cells causes illness

Name names three intrinsic factors and three extrinsic factors that affect microbial growth in food products.

Answer: Intrinsic: water activity, pH, nutrient content; Extrinsic: temperature, storage environment, humidity.

What microorganism was responsible for the potato famin in the mid-19th century?

Phytophthora infestans

What foodborne pathogen can cause peptic ulcers?

Helicobacter pylori

What is defined as the ability of meat to retain its water during application of external forces such as cutting, heating, grinding, or pressing?

water holding capacity

What are the two general types of adulteration of foods?

economic adulteration; addition of foreign material

The ability of an organism to survive thermal processing is termed what?

Heat resistance

Name the toxin present in Tonka beans.

Coumarin (1-3%)

List one of the three safe methods to defrost food.

refrigerator thawing, cold water thawing, microwave thawing or (cooking without thawing)

BHA and BHT are common antioxidants. What do these acronyms stand for and how much of these are allowed by law to be used in foods?

BHA – butylated hydroxyl toluene, BHT = butylated hydroxyl anisole 0.01% of fat content individually or 0.02% of the fat content of the food (when 2 or more are used together)

What structures do bacteria such as e. coli use for movement?

Flagella

Juice or beverage spoilage by Alicyclobacillus primarily leads to what spoilage compound, associated with a medicinal off odor?

Guaiacol

List four method used to find the total number of microorganisms in foods.

pour plate, surface spread plate, surface drop, agar droplet, and microdilution

What is the lethal rate used to calculate?

converts the thermal death time at temperature T to equivalent thermal death time at a reference temperature in order to destroy the same population of spores

Shigellosis is caused by the bacteria Shigella. What common practice can greatly reduce your chances of contracting Shigellosis?

hand washing

A pink color in sauerkraut indicates the presence of what?

Yeast

What is the predominant component of the Gram (+) cell wall?

Peptidoglycan

What is the most common psychotropic bacteria associated with milk spoilage?

Pseudomonas species

What is the food-borne illness associated with “red tide”?

paralytic shellfish poisoning

Lists the four steps, in proper sequence, for cleaning and sanitizing food equipment.

Rinse, clean, rinse, sanitize

From what source is C. bot first isolated?

Smoked ham

Guillain-barre syndrome caused by?

camphylobacter jejuni: ascending paralysis

Name in microbial reduction process for spices and seasonings.

Answer: irradiation

How are bacteria grouped according to Bergey’s Manual?

gram reaction, morphology (rod or cocci), growth with or without oxygen, by familia

What are the two selected agents in Baird-Parker media?

is a medium for the enumeration of Staphylococcus aureus in foods which was first reported by Baird-Parker (1962) contains Lithium chloride and tellurite

Genera for Downy Mildew disease.

Sclerospora bremia

What does “GRAS” stand for?

generally recognized as safe

What is an indicator organism?

An organism used to test changes in water quality conditions or food microbiological analysis by detecting for the presence of harmful pathogens .

A characteristic of an "emetic" form is that it causes nausea but not ...

diarrhea

Define thermal death time.

the time it takes to kill a specific bacteria at a specific temperature

What are three genera of fungi commonly used in food production?

Aspergillus, Penicillium, Fusarium, Saccharomyces

What are mycoses?

When molds and fungi colonize body surfaces. There are various types, categorized based on how deep into tissues they inhabit.

Top 3 microbial causes of foodborne illnesses.

Norovirus, salmonella, clostridium perfringes

In general, microbial survival curves follow what type relationship?

first-order exponential

Integration of lethality will determine which value?

F- value

What is the D value?

Time in minutes, at specified temperature to destroy 90% or 1 log reduction of the microorganisms in a population.

How many square centimeters in a standard Petri dish?

35mm--area of 8.55 square cm. 50 mm or 5 cm--area of 19.60 square cm. 100 mm or 9 cm-- area of 56.75 square cm. 135 mm-- area of 143 square cm.

In 1963 the FDA approval for a new processing method was given, only to be revoked in 1968. What was the product and the process?

bacon and irradiation

Integration of lethality will determine which value

F sub zero

What foodborne parasite is found in cat litter?

Toxoplasma gondii

Name one chemical compound that is used to sanitize food processing equipment.

NaOCL and quats

Two bacteriocides allowed in foods.

xanthan gum, gellan gum

What microbe is used to make vinegar?

Acetobacteria

Claviceps purpurea causes what type of food poisoning?

ergot

The sterilization value, also known as F sub zero describes what?

the integrated impact of time and temperature on the microbial population, expressed as time at the reference temperature, calculated by using the lethal rate times heating time

Which mycotoxin is associated with liver cancer? a. aflatoxin b. ochratoxin c. patulin

a. aflatoxin

Which foodborne pathogen also causes necrotic enteritis in poultry and gas gangrene in humans?

Clostridium perfringens

What exemption is given to unpasteurized citrus juice under the FDA juice HACCP rule?

The 5 log reduction can be done cumulatively through treatments of the fruit and other steps in the process, rather that on the juice itself as required for all other juices

Outbreaks of Salmonellosis from consumption of raw almonds in 2000 and 2004 were caused by rare phage types of Salmonella Enteritidis. What were these two rare phage types?

PT 30 in 2000 and PT 9c in 2004

What is the difference between food spoilage and food poisoning?

spoilage = inedible food but not unsafe(judgmental to what is not acceptable); poisoning = causes illness through infections(detrimental effect to system)

What are some advantages of aseptic processing?

convenience (many foods can undergo aseptic processing), safety (protect against spoilage and foodborne illness), flavor and freshness (captures the natural flavors and has a fresh clean taste), natural (no need for preservatives)

What is a bacteriophage?

A virus that infects bacteria.

Below what pH can Clostridium botulinum spores no longer germinate?

below pH 4.6

What is the microbial gum commonly used in salad dressings?

Xanthan gum

What are the shapes of following divisions of bacteria? cocci, bacilli, spirilla, vibrios, spirochaetes

spherical (cocci), rod (bacilli), spiral (spirilla), comma (vibrios) and corkscrew (spirochaetes)

What is an incipient contaminant?

naturally present on the food product

How is fungi differentiated from algae and other higher plants?

It lacks chlorophyll

What genera of gram negative, facultative anaerobe are catalase positive, oxidase negative, ubiquitous and cause foodborne illness?

Salmonella

Is the osmotic pressure higher or lower inside a growing cell as compared to the external environment?

Higher, Cell elongation during growth is followed by influx of water into the vacuole

Name 3 of the 16 gram negative, facultative anaerobic rods.

Enterobacteriaceae, Arsenophonus nasoniae, Buttiauxella agrestis, Cedecea, Citrobacter, Edwardsiella, Enterobacter, Erwinia, Escherichia, Ewingella americana, Hafnia alvei, Klebsiella, Kluyvera, Leclercia adecarboxylata, Leminorella, Moellerella wisconsensis, Morganella morganii, Obesumbacterium proteus, Pantoea, Pragia fontium Proteus, Providencia, Rahnella aquatilis, Salmonella, Serratia, Shigella, Tatumella plyseos, Xenorhabdus, Yersina, Yohenella regensburgei, Aeromonas, Enhydrobacter aerosaccus, Photobacterium, Plesiomonas shigelloides, Vibrio, Actinobacillus, Hemophilus, Pasteurella, Calymmatobacterium granulomatis, Cardiobacterium hominis, Chromobacterium, Eikenella corrodens, Gardnerella vaginalis, Streptobacillus moniliformis, Zymomonas

What are the spore-forming foodborne pathogens?

bacteria such as the Bacillus and Clostridium species are able to form spores. These spores, also referred to as endospores, are the dormant form of vegetative bacteria and are highly resistant to physical and chemical influences.

Ingestion of crickets may cause which type of allergen reaction?

shell fish crustaceans

What type of bacteria besides Staphylococci aureous can survive on cows utters?

Micrococci

What bacterial neurotoxin is used for cosmetic procedures?

Botulism toxic

What is the 12D process?

the time/temperature process that will reduce the microbe spore population (typically C. bot) by 12 log cycles

In 2008, the author of Modern Food Microbiology, currently in its 7 revision, passed away. Who is this author?

James Jay

The Howard Mold Count was developed as a method of monitoring the quality of what type of food products?

Tomato products

When testing for c. perfringens, what is the only test result that is negative suggesting a positive confirmation of c. perfringens?

motility

Which genera contains bacteria that can fluoresce and contains members that commonly cause spoilage of fresh cut vegetables and meats?

Answer: Pseudomonas flurescens

Define fecal coliforms and indicate the reason that they are often evaluated in foods.

facultative anaerobes (organisms which can survive in the absence of oxygen), gram-negative, non-spore forming, rod-shaped bacteria that ferment lactose (a type of sugar), producing gas and acid within 48 hours when cultured at 35oC. Their lack of ability to form spores makes them more susceptible to destruction by environmental conditions.they are used as indicators of fecal contamination

What is an exotoxin?

Toxic proteins secreted by bacteria and released outside of the cell

Koch's postulates to determine disease causing microbes

(1) The microorganism must be found in diseased but not healthy individuals; (2) The microorganism must be cultured from the diseased individual; (3) Inoculation of a healthy individual with the cultured microorganism must recapitulated the disease; (4) The microorganism must be re-isolated from the inoculated, diseased individual and matched to the original microorganism.

Three types of shellfish poisoning:

paralytic, neurotoxic, amnesiac, diarrhetic

Term used to describe a compound causing defects in growing featus?

teratogen

What are the five major classes of micro organisms based on temperature?

Mesophile thermophile, psychrotroph psycrophile extremophiles

What value measures the heat resistance of a microorganism?

D-value

What property does Aspergillus glaucus have that allows it to grow on dried fruit?

It is xerophilic, and grows where there is a low availability of water

Genus and Species of the bacteria involved in the Irish Famine.

Phytophthora infestans

Define the concept of thermal death time.

the time to kill a given number of organisms at a given temperature under specific conditions

What is the incubation period for Listeria monocytes?

3-70 days

Which bacteria must be tested for under the final rule for pathogen reduction and HACCP? And which bacteria should meet performance standards?

generic E. coli, Salmonella

What are the 5 main types of botulism?

foodborne, infant, wound, Adult intestinal toxemia, Iatrogenic botulism

Name the body of FAO-WHO that deals with food standards including pesticides.

Codex Alimentarius commission

St. Anthony's Fire outbreaks are now very rare. It is caused by a toxin on rye or wheat produced by what ?

claviceps purpurea

Name the toxic substances in unprocessed cassava roots.

cyanogenic glycosides (lenamaric, lotaustralin)

What is the difference in a wild and controlled fermentation?

Controlled adds microorganism and wild uses those already present

Lactic acid bacteria are a group of gram positive bacteria that are normally acid tolerant and produce lactic acid from a carbohydrate source. Name 5 species of lactic acid bacteria.

Leuconostoc, Lactobacillus, Lactococcus, pediococcus, streptococcus

What is a bacteriophage composed of?

A nucleic acid molecule surrounded by a protein structure.

What does "ETEC" stand for in microbiology?

Enterotoxigenic E. coli

What are the 2 types of food poisioning possibly recieved from consuming fish?

ciguatera and scombroid

How hot should you cook a burger before eating it?

160 degree F

Name five yeast fermented food products.

beer, wine, bread, distilled spirits, kefir, kombucha, root beer

Name 5 spices that have antimicrobial activity.

garlic, cinnamon, cloves, onion, horseradish, and mustard

What are some of the disadvantages of using the general method to calculate lethality?

the initial temperature and time/temperature profile used in production must remain consistent with those used at the time of the heat penetration tests, not recommended for process development, there is a need for thermocouple nad measurement accuracy (with accurate calibration)

Coliform general characteristics.

rod-shaped Gram-negative nonspore forming and motile or nonmotile bacteria that can ferment lactose with the production of acid and gas when incubated at 35–37°C.

What are some viruses that cause foodborne human illness?

hepatitis, rotavirus, norovirus virus

What is the name of a polypeptide antibiotic produced by some streptococcus lactis strains?

Nisin

A bacteria, yeast, fungi, or filamentous genetic material has been changed in nucleic aicd modification by FAO/WHO is termed what?

Genetically modified

What are the 2 principle mechanisms by which preservatives stop the growth of microorganisms?

water availability and acidity

What is the ‘best if used by/best before’ date used for?

a guide to the quality or flavor profile of a food product

What is the medical term or name given to the condition where bacteria are actively multiplying in the bloodstream?

Septicemia

Explain pasteur effect.

the rate of glycolysis under anaerobic conditions is higher than the rate under aerobic conditions. Aerobic: citric acid cycle follows glycolysis; anaerobic: fermentation occurs

What is an emerging infectious disease (EID)?

an infectious disease whose incidence has increased in the past 20 years and could increase in the near future

What is patulin, with what food products is it associated, and how is it usually analytically determined?

A mycotoxin formed by Penicillium, Aspergillus and Byssochlamys genera associated with apple juice products; determined by High Performance Liquid Chromatography

How many seconds should you wash your hands as stated by the CDC?

20 s in US, 15 s in Canada

Microorganisms that can survive low water activity conditions are called

xerophilic

What is the d value?

the decimal reduction time or the time required to destroy 90% of microorganisms

Name five genera of bacteria that are considered to be lactic acid bacteria.

lactobacillus, leuconostoc, lactococcus, pediococcus, streptococcus

Sanitation and inspection recommendations for adoption by state and local regulatory agencies for inspection of food retail and food service facilities are in the ________

FDA Food Code

What are psychrophiles?

Bacteria or archae that grow over the range of sub zero to 20 C with an optimum around 15 C

What causes trichinosis?

It is a type of roundworm infection is acquired by eating Trichinella species larvae in raw or undercooked meat

What is the maximum ERH considered safe for grain storage?

70% (around 80% ERH moisture grain results in increased respiration and temperature increases)

In reference to Aflatoxin B1, what does the B designate?

blue fluorescence

What are some disadvantages of using the formula (ball) method to calculate lethality?

only can use at a constant retort process temperature, the cooling portion modeling is empirical and may over/under estimate lethality

What are the core messages of the five keys to safer food outlined by the World Health Organization?

Keep clean, separate raw and cooked, cook thoroughly, Keep food at safe temperatures, use safe water and raw materials

A positive catalase test shows the formation of _______ when hydrogen peroxide is added.

Effervescence due to the in vitro Oxygen production

What are the three spore-forming foodborne pathogens?

bacillus cereus, clostridium perfringens, clostridium botulinum

Name the main microorganism used in malolactic fermentation.

Oenococcus oeni

Another name for thermal death time is

F value or sterilization value

Give the temperature and z value for the commonly used/standard F sub zero value that is based on the destruction of a population of C. botulinum.

temperature: 18 F or 10 C, z value: 250 or 121

Why was Schwan’s ice cream recalled from the marketplace in October of 1994?

presence of Salmonella

What are the 5 major classes of microorganisms based on temperature?

Psychrophiles, psychrotrophs, mesophiles, thermophiles, hyperthermophiles

What is spice is very dangerous if it is injected intravenously?

nutmeg

What is the main disadvantage of commercial sterilization of a food?

significant changes in nutritive and sensory characteristics

What type of HACCP hazard would jewelry be considered?

Physical

What organisms do the following media select for and how do the colonies appear on the media? XLD (xylose lysine deoxycholate), VRBA (violet red bile agar), EMB (eosin methylene blue), baird parker, macconkey

f) XLD- salmonella- red colonies- black centers and shigella-red colonies g) VRBA- enterobacteriaceae, pink colonies h) EMB- coliforms, E.coli turns metallic green i) Baird Parker-staph aureus- black j) Mcconkey- Macconkey- coliforms, pink- if lactose fermenting, colorless if not, E.coli, Enterobacter aerogenes, Staph aureus, Salmonella Typhimurium, Proteus vulgaris

What two organisms are involved in vinegar production and in what order?

s. cerevisiae and acetobacter

Formula to calculate D-value.

D1 = D2 × 10(T2 - T1)/Z

An initial population of 50,000 bacteria grows with a generation time of 30 minutes. About how many bacteria will be present 3 hours later?

3200000

Sneeze guards are placed on salad bars to protect food from which of the following; campylobacter jejuni, escherichia coli, salmonella, staphylococcus aureus?

Staph aureus

True or false: the following steps should be followed for cleaning food contact equipment and utensils: 1) prerinse 2) soap and scrub (washing) 3) rinse 4) sanitize 5) air drying

True

What are hemolytic bacteria?

bacteria that can lyse blood cells

What is the function of heterofermentative lactic acid bacteria in fermented foods?

production of flavor compounds (acetaldehyde and diacetyl) (homofermenters increase acidity)

What is the primary purpose of retorting low aci canned foods?

reduce spores of C. bot by 10^12

What spoilage organisms are most likely to be found vacuum packed, refrigerated meats held for several weeks?

clostridium perfringens

Name three metabolic products of heterofermentative microorganisms.

acetic acid, ethanol, formic acid, and CO2

What are the 2 distinct syndromes of B. cereus gastroenteritis?

vomiting (emetic) type, diarrhea type

What is the minimal water activity for most molds?

0.75-0.80

Media and what they are used for: MYP, BHI, XLD

MYP (mannitol egg yolk polymyxin): bacillus cereus BHI (Brain heart infusion): listeria XLD (xylose lisine deoxycholate): salmonella

Define endotoxin.

Endotoxin is a complex lipopolysaccharide (LPS), a toxic substance found in the outer membrane of most gram-negative bacteria

Where in the US are C. botulinum type A, B, and type E generally found?

type B toxin causes most cases of botulism in horses in the midwestern and mid-Atlantic states of the U.S., while type A is usually responsible for equine cases in the western states. . Type E-producing C. botulinum strains tend to occur in coastal areas and other aquatic environments

What are the ingredients of TGY agar?

trypton, glucose and yeast extract

In the US the legal processing for low-acid foods requires what?

exposure to temps for a period equal to 12 D values fo C. botulism

In August of 2020, there was a multi-state outbreak of Salmonella enterititis in which fruit?

peaches

The D value of green peas is 0.2 minutes. What is the F value at 250 Fahrenheit?

12D so 2.4 minutes

Work done between 1895 and 1898 by Underwood and Prescott.

Time-temperature combinations for various canned foods to remove spoilage microorganisms. Thermal processing for canning.

What bacteria is found in foods that produce harmful toxins, is heat resistant but won’t grow in acidic foods?

Clostridium Botulinum

Why do bacteriologists incubate pathogens at 37 deg C?

it is the human body temperature

During which phase of microbial growth is bacteria the easiest to kill?

log or exponential phase

What is LD50?

The amount of an ingested substance that will kill 50% of a test sample. Expressed in milligrams of substance per kilogram of body weight.

What organism is included in the fermented sausage starter culture?

Pediococcus cerivicea

How many infections of C. Botulism is required to be considered an outbreak?

In a HACCP plan, an undeclared allergen contamination is considered as what type of hazard?

Chemical

Name 5 microorganisms that have been associated with food poisoning outbreaks.

C. botulinum, C. perfringens, B. cereus, S. aureus, Salmonella, Shigella, Vibrio parahaemolyticus, E. coli, Listeria monocytogenes

What type of bacteria love high heat?

thermophiles

Give the genus and species of the organism that produces xanthan gum

Xanthamonas campestris

Name 2 conditions under which yeasts and molds will out compete most bacteria

1) low Aw (0.6-0.7) 2) 2 > pH > 9

What organisms produce a yellow colony on Mannitol salt plates?

Staphylococcus aureus

Which form of mercury is associated with sea food toxicity?

Methyl or organic mercury

Given the highest dose of a chemical that causes no effect in rats is 300mg; what is the accepted daily intake for humans?

3 mg, (100 fold safety factor)

Name 3 strains of mold that produce mycotoxin.

Aspergillus flavus, Aspergillus parasiticus, Claviceps purpurea, Penicillium citrinin, Penicillium expansum, Fusarium spp.

What are the 2 main methods of plate counting?

Spread and pour plating

A 6D process reduces the population of the target organism by what percent?

0.999999

For what foods has irradiation been approved as a preservation method?

Poultry, pork and spices

What is the major assumption made when dealing with CFU in microbiology?

Each individual colony is originated from one original bacterial cell All the cells within each colony forming unit is homogenous

What are the intrinsic and extrinsic factors for microbial growth in food?

intrinsic: pH, water activity, redox potential, biological structure, moisture content,animicrobial component , competitive microflora, nutrient content Extrinsic: temperature and time, relative humidity, gaseous environment, presence of other organisms, processing operations, type of packaging

Classify the followng microorganisms into intoxication or infection: C. bot, Campylobacter jejuni, Staph aureus, Aspergillus flavus, Salmonella

C. bot: intoxication, Campylobacter jejuni: infection, Staph aureus: intoxication, Aspergillus flavus: intoxication, Salmonella: infection

What are some of the advantages of using the general method to calculate lethality?

simple to perform, most accurate method as long as: temperature measurement is accurate, time interval is reasonable, and a proper integration method is chosen, is a good tool for process evaluation

What is a facultative anaerobe?

a microbe that can grow with or without oxygen

What three terms, respectively, are used to describe the ability of microorganisms to grow at cold, ambient and warm temperatures?

psychotrophic (or psychophilic), mesophilic, thermophilic

Give the genus and species of 3 molds that are used in the production of blue cheese.

Penicillium roqueforti, Alt. names: P. glaucum, P. gorgonzola and P. stilton

What pathogenic bacteria can grow at aw=0.86 ?

Staph Aureus

What is the name of potent carcinogen produced by mold in corn.

Aflatoxin

What are the m/o responsible for traveler's diarrhea?

e. coli

Which common food borne bacterial pathogen is microaerophilic and requires temperatures above 32 degrees C for growth?

Campylobacter jejuni

Baird parker mediums are used to detect and enumerate which organism or groups of organisms?

Staphylococcus aureus or staphylococci

What does "TA" mean in regards to spoilage of canned food?

Thermophilic anaerobic

What does CFU stand for?

colony forming units

Name one example of each of the following used in food and beverages industry: Fungi Yeast Mold Bacteria Single-cell food

Fungi: Actinomucor, Amylomyces, Mucor, Rhizopus, Monascus, Neurospora, Aspergillus, Penicillium, Candida, Endomyces, Hansenula, Saccharomyces, Torulopsis, Trichosporon, Zygosaccharomyces/ Just say mushrooms Yeast: Saccharomyces, Kluyveromyces Mold: Aspergillus, Penicillium, Rhizopus, Neurospora Bacteria: Lactobacillus, Lactococcus, thousands of names Single-cell foods: eggs, microalgae such as spirulina, chlorella

The USDA-FSIS currently (2008) recognizes high-pressure processing as an acceptable food safety intervention for eliminating which food pathogen from processed meat products

Listeria monocytogenes

What is the most effective way of inactivating botulism toxin?

Heat

A microbial population has been decreased by what percentage when it undergoes a one-log reduction?

0.009

Besides extending shelf life and preventing microbial growth, what is another benefit of reducing the water activity of a food?

a lower water content means a lower product volume, making the product easier and cheaper to transport

What is the number of equivalent minutes at 121 C delivered to a container of product calculated using a z value of 10 C known as?

F or sterilization process equivalent time

What is the most common psychrotropic bacteria?

Pseudomonas

What is LD50 value?

dose of a substance that will kill 50% of the test subjects

What food is most associated with the foodborne illness agent enterobacter sakazakii?

Infant formula

Identify three types of fungi commonly consumed in foods.

Yeast, molds and mushrooms

What is the common name of transmissible spongiform encephalopathy, a neurological disease found in sheep?

Scrapie

The organism that causes 'flat sours' in canned tomatoes is

bacillus stearothermophilus

Which microorganism creates a heat stable toxin?

Staphylococcus aureus

What genus of microorganisms are most often involved with spoilage of refrigerated fresh meat, poultry, fish, and eggs?

pseudomonas

This word means "sausage poisoning". It is caused by a powerful toxin that affects the nervous system.

botulism

What does FSIS stand for?

Food safety and inspection service

What is the full name of MRS agar used for lactobacilli cultures?

De Man, Rogosa and Sharpe agar

What are psychrotrophs?

Psychrotrophs are cold-tolerant bacteria or archaea that have the ability to grow at low temperatures, but have optimal and maximal growth temperatures above 15 and 20°C, respectively.

What yeast is used in soy sauce production?

Zygosaccharomyces rouxii and/or Torulopsis spp.

Define “defect action level”.

the level of contamination that calls for seizing a product.

Name the common method used to detoxify aflatoxin in corn.

treatment with ammonia

How does Food irradiation kill pathogens?

The ionizing radiation sends enough energy into the bacterial or mold cells in the food to break chemical bonds.

What is the D value of a microorganism that is decreased in population by a factor of 10 in 2 minutes?

Two

Name one example of each of the following used in food and beverages industry: Fungi Yeast Mold Bacteria Single-cell food

What is a mycotoxin?

Secondary metabolites produced by microfungi that can cause disease and death in humans and animals.

What organism is responsible for Q fever?

coxiella burnetii

What does aerogenic bacteria produce?

Gas

What does E. stand for in E. coli?

Escherichia

What is the organism (genus) most commonly associated with food poisoning?

salmonella

Cyanogenic glycosides are compounds that when treated with an acid or appropriate hydrolytic enzyme yield what compound?

cyanohydron

What is zoonosis?

disease spread to humans from vertebrate animals

Botulism was given its Latin-derived name because it was associated with what food?

Sausage

What is the protein coat of a virus call?

Capsids

At what temperature are bacterial spores destroyed?

250 F

What are the 3 most common types of human botulism?

Type A, B, E, F (rare)

What is the most common pathogen found in cheese outbreaks?

Monocytogenes

With fermented cucumbers or cabbage, why is salt added?

to discourage the growth of Pseudomonas and enterobacteria

Define Lactic acid bacteria.

gram-positive microorganisms known as the main safe industrial-scale producers of lactic acid (LA)

In the MUG test, what enzyme from E. coli is being tested?

B-glucuronidase

What is the measurement of oxygen utilized in the stabilization of organic matter by microorganisms over a 5 day period at 20 C called?

biological oxygen demand

Name any 1 mold (either in spore form, germinated cells, mycelium) that can be found in blue cheese.

Penicillium roqueforti, P. glaucum, Penicillium stilton, Penicillium gorgonzola

The Christie—Atkins—Munch-Peterson (CAMP) test is used to identify what foodborne pathogen?

Listeria monocytogenes

What causes ergotism (st. anthony's fire)?

caused by eating toxic alkaloids produced by the fungus Claviceps purpurea. On wheat, barley, rye, oats, and wild grasses. Max. level of ergot allowed 0.1% dry weight in barley, oats, 0.3% dry weight in wheat and rye

What type of botulism is mainly involved in seafood?

type e

What is the difference between food infection and food intoxication?

Intoxication: Toxin is produced in the food before it is ingested. Infection: Viable cells must be consumed and the pathogens must grow inside the body to cause symptoms

What is zoonosis?

transmittance of disease from vertebrates to humans

What toxin-producing Gram-positive cocci can cause illness within 30 minutes of eating contaminated food?

Staphylococcus aureus

What is a secondary metabolite produced by fungi and can cause unnatural or "deleterious biological changes in plants, animals, humans, or microorganisms?

mycotoxin

What organisms are responsible for scombroid poisoning in seafood?

Morganella morganii, Escherichia coli, Klebsiella, and Pseudomonas aeruginosa

According to the World Health Organization, the genus of bacteria is the most common cause of human gastroenteritis in the world.

Campylobacter.

What is the most heat resistant pathogen found in milk?

Coxiella burnetii

Define the D-value and the Z-value.

z-value – temperature required to decrease the time necessary to obtain a 1 log reduction in cell number to 1/10th of the original value d-value – the time in minutes at a specific temperature to reduce the number of microogranisms by 1 log cycle, AKA kill 90% of micorbes.

In order list the 7 steps of HACCAP.

1. Conduct a hazard analysis, 2. Identify CCP, 3. Set critical limits, 4. Establish monitory procedures, 5. Establish corrective actions, 6. Verification, 7. Establish record keeping

What is used to pasteurize spices?

ethylene oxide or gamma radiation

Name one bacterium that is in the nodules of roots of leguminous plants.

rhizobium

Which genus of bacteria are used in the production of kimchi?

Lactobacillus

From what source was Clostridium botulinum first isolated?

Answer: Smoked ham

The primary yeast used in baking is what?

Saccharomyces cerevisiae

Which describes a class 2 recall? a. minor violations not subjecto FDA action b. exposure but no health consequences c. exposure may cause health consequences d. reasonable use or exposure will causes serious health consequences

c. exposure may cause medically reversible health consequences

The magnification of a microscope with an eye piece of 10X and an objective of 97 X is what?

970X

What is a food infestation?

the consumption of a food containing a parasite

What are 4 major tests for allergies?

oral challenge, RAST, skin test, Immunoblotting and Basophil release

At what pH can a food be called an acid food?

a pH less than 4.6

What microorganism is used to manufacture the fermented soybean product tempeh?

rhizopus oligosporus

Another name for thermal resistance constant is

z-value

Which protein in eggs has antimicrobial properties?

Lysozyme

Which single bacteriocin is approved for food preservation in the US? Which product is it used in?

Nisin, for pasteurized cheese product.

What are the microbial inhibitors in egg whites and how do they work?

The albumen is beneath the shell membranes and is important in providing three antimicrobial defenses to the egg. The first defense is the viscosity of the albumen components, which provide conditions in which bacteria cannot move easily. The second defense is the alkaline pH of the albumen that initially ranges from 7.6 to 7.8 but quickly increases over a period of a few days due to the loss of carbon dioxide during storage, resulting in a pH of 9.1–9.6. This is a pH range that is not conducive to the growth of most microorganisms. The third defense is the presence of a number of proteins and glycoproteins that possess antimicrobial activity.(See additional info)

How do microbial inhibitors work?

By acting on the whole cell, cell wall, or cell membrane in order to interfere with the genetic mechanism of the cell, interfering with the enzyme systems of the cell, or by binding to essential nutrients to kill the cell or stop reproduction.

In University, TA is typically understood to mean teaching assistant. However, this initalism also refers to what type of spoilage in canned food?

Thermophilic, anaerobic spoilage

What is the main source of vibrio cholerae?

shellfish

What is the minimal water activity for most bacteria?

0.90-0.91

What does GMP stand for?

Good manufacturing practices

When viewed under a microscope after gram staining, gram negative bacteria appear what color?

Red

Toxins produced by molds are called _________?

mycotoxins

The enumeration technique for microorganisms which uses 3 sets of tubes with, 3, 5, or 10 tubes per set is called what?

most probable number

What toxin causes acute liver damage?

Aflatoxin

The presence of beta-giucuronidase signifies the presence of what microorganism?

Escherichia coli

What are 2 types of microbiological testing used to identify and verify microorganisms in foods?

culture media, immunoassay, or polymerase chain reaction.

What is the time necessary at a given temperature to sterilize a suspension of bacteria and their spores (if they form spores)?

Thermal death time

What is the name of the toxin family responsible for the majority of seafood illnesses?

Phycotoxins

What are facultative anaerobes?

microorganisms that can grown and survive with or without oxygen

In anaerobically stored fresh meat, what is the major type of spoilage organism?

Lactic acid bacteria

What is the most common way to avoid a foodborne illness?

Wash hands

What is the sweetener found in some peanut butter that may be toxic to dogs?

Xylitol

What end product does the Voges-Proskauer test detect?

Acetoin

Lysine is produced by which genus of bacteria?

Brevibacterium

Sauerkraut results from what kind of fermentation process

Lactic acid

What does SPC stand for in microbiology?

Standard plate count

What form of mercury is associated with seafood toxicity?

org Hg or methyl Hg

What is the "F" value?

Minutes required to destroy a given number of microbes at a given temperature

Name one chemical compound that is used to sanitize food processing equipment.

Hypochlorites, quaternary ammonium, Peroxyacetic Acid (PAA)

Xenobiotic definition?

substances that are foreign to the body or to an ecological system

Give the genus/species of the organism used in processing Brie and Camambert cheeses what forms a white crust.

Penecillium Camambertii

What is the minimum pH of growth for most Gram negative aerobic bacteria?

5.3

Another name for decimal reduction time is?

D-value

Determine whether the following characteristics are of eukaryotic or prokaryotic cells:

does not have membrane bound organelles (pro) true nucleus (eu) Size 10 ^100 (Eu) does not have membrane bound organelles (pro) unicellular (pro)

What is an indicator organism in food microbiology?

an indicator of sanitary conditions

What organism causes typhoid fever?

Salmonella typhi

In sauerkraut production, salt promotes the growth of what group of bacteria?

lactic acid bacteria

On what food stuff is the mycotoxin patulin most commonly produced on?

apples

What is the time temperature combination required for foodservice operators to safely cool cooked foods?

Answer: food must be cool to 70 degrees Fahrenheit within two hours, and then 41 within four hours, and the total cooling time should not exceed six hours.

The quality assurance system called HACCP stands for ...

Hazard Analysis Critical Control Points

A thermal death curve plots ___ against _____.

temperature vs. time

What is the causative organism for flaccid paralysis?

c. botulinum

What is the z value of Clostridium botulinum?

10 C or 18 F

Name three methods for the calculation of lethality.

general, formula (ball) method, and numerical

What are the 7 steps of HAACP?

Conduct a hazard analysis, identify critical control points, establish critical limits, monitor critical limits, define corrective actions, establish verification, keep records

Botulinum toxin type H is the deadliest substance in the world, but type A is used for what commercial application?

Botox

Which microorganisms make the following hydrocolloids?

xanthan - xanthomonas campestris, curdlan - alcaligenes faecalis var. myxogenes, gellan - pseudomonas elodea

The time in minutes required to destroy 90% of a population at a given temperature.

D value – decimal reduction time

Potassium sorbate can be applied to sausage casings before or after stuffing to retard what?

Yeast, Molds, and select bacteria

What is an enzyme that catalyzes the reduction of hydrogen peroxide to oxygen and water?

Catalase

Which genera of bacteria can fluoresce and spoil fresh cut vegetables and meat?

Pseudomonas

In 1989, the pork industry began a national eradication program for what virus, which is nearing completion?

Pseudorabies

What are the typical organisms used in the production of cottage cheese?

lactococcus lactis subsp lactis, lactococcus lactis subsp. Cremoris; homofermentative fast acid producing

What organism is used in the manufacture of blue cheese?

penicillium Roqueforti and Penicillium Glaucum

Name 3 instrument and extensive factors that affect microorganisms growth in foods.

Temperature, water activity, pH

How does food irradiation kill pathogens?

Genetic material is disrupted

What is the single most important phase of a sterile canning operation?

retorting

The Ames test is used to identify which organism? a. E. coli b. Staph aureus c. Salmonella __? d. Salmonella typhimurium

D. Salmonella typhimurium

Classifying the following microorganisms if they cause intoxication or infection regarding foodborne illness: Clostridium botulinum, Campylobacter jejuni, Staphylococcus aureus, Aspergillus flavus, and salmonella species.

Answer: C.bot – toxin (botulinum toxin), Campy (infection), Staph (intoxication, Amongst the more common toxins secreted by S. aureus are hemolysin, leukotoxin, exfoliative toxin, enterotoxin, and toxic-shock syndrome toxin-1 (TSST-1).), A. flavus (aflatoxin), Salmonella (infection).

Name three bacteria commonly associated with food poisoning. (Does not need to be full scientific name.)

Salmonella, Norovirus, Campylobacter, E. coli, Listeria, Clostridium perfringens

Name a bacteriocin approved for use in the US.

nisin

What is the area under a lethal rate curve defined as?

lethality

Which lactic acid producing bacteria found in sourdough bread takes its name from a California city?

Lactobacillus sanfranciscensis

According to the USDA, what are the three safe ways to thaw frozen foods?

Refrigerate, immersion in cold water, microwave thawing

Why are enrichment techniques used when examining food for the presence of salmonella?

salmonella re usually present in small numbers. Enrichment allows salmonella to grow and outcompete non-salmonella microbes and also allows recovery of injured cells

The International Association of Milk, Food and Environmental Sanitarians (IAMFES) have recently undergone a name change. What is the new name for this organization?

International Association for Food Protection (IAFP)

Name two anti-microbial factors found in raw milk.

Lactoperoxidase, lactoferrin, lysozyme

What aspect of Staphylococcus aureaus does selective media 111, exploit?

Salt tolerance

Intrinsic factor in foods which affect microbial growth

pH, redox potential, nutrient content, water activity

Protein coat of virus is called:

Pepsid

What is the likely source of the hemorrhagic e. coli that contaminates hamburger?

cow's cut during slaughter

Name the fungus responsible for Ergot.

claviceps purpurea

What is the main assumption made when dealing with CFUs in microbiology?

every colony is separate and founded by a single viable microbial cell.

Why is listeria monocytogenes of greater concern in refrigerated foods than in foods stored at ambient temperature?

L. m. is a psychrotroph that selectively grows at low temperatures

You are starting to feel nauseous and remember possibly eating some undercooked chicken a few days ago. What type of bacteria is most likely making you sick?

campylobacter (2-5 incubation days)

Food infection is when the food contains bacteria or other microbes which infect the body after it is eaten.

intoxication: S. aureus, C. botulinum, B. cereus, C. perfringens. Infection: E. coli, L. monocytogenes, Salmonella enteritidis spp, Yersinia enterocolitica, Camylobacter jejuni, etc.

Define mycosis.

disease resulting from the invasion of living cells by a fungi

What genus and species is used in the manufacture of blue cheese?

Penicillium roqueforti

Why is listeria monocytogenes of greater concern in refrigerated foods than in foods stored at ambient temperatures?

listeria monocytogenes is a psychrotroph that selectively grows at low temperatures

Name the microorganism associated with Ergot poisoning.

Claviceps purpurea

Botulinum toxin type H is the deadliest substance in the world, but type A is used for what commercial application?

Botox

Name 3 blotting techniques.

southern - DNA; Northern - RNA; Western - protein

What spoilage compound is associated with a medicinal off odor caused by alicyclobacillus?

Guaiacol

Give the name and type of food borne illness where the pathogens are consumed, take up residence in the intestinal walls and produce a toxin inside the body, and give an example

food toxicoinfection.. E. coli O157: H7

What science deals with the harmful effects of chemicals on humans?

Toxicology

Which medium is used to detect and enumerate Staphylococcus aureus directly in foods? A. apt agar, B. Baird-Parker agar, C. Potatoe dextrose Agar, D. Violet red bile agar

B. Baird-Parker Agar

Name one genus of bacteria that can cause ileocecitus, a disease that mimicks appendicitis.

Yersenia, Camplyobacter, Salmonella

In September 2020, dried woodear mushroom were recalled because of which Salmonella serovar?

Salmonella stanley

What are the three major genera of mycotoxin producing fungi?

aspergillus, penicillium, fusarium

Which thermoduric, acidophilic, spore forming bacterial species is an emerging spoilage issue for juice and beverage processors?

Alicyclobacillus

When counting bacterial colonies, the acronym TNTC stands for what?

Too numerous to count

What is the water activity to cause spoilage for bacteria, yeast, and molds?

Bacteria - 0.9, Yeast - 0.85-0.9, Mold 0.75-0.8

Who disproved the theory of spontaneous generation?

Louis Pasteur

What bacterial form can survive boiling at 100 deg C for 30 minutes?

the spores

What organism can cause symptoms similar to appendicitis?

yersinia enterocolitica

What is the indicator organism used for thermal processing?

Bacillus stearothermophilus

Name, a species of Aspergillus. capable of producing aflatoxins.

Aspergillus flavus

Name 2 ways yeast divide.

Budding (a special kind of mitosis) and Meiosis

What is the most common source of foodborne illness in Japan?

vibrio from seafood.

What mycotoxin is produced by a mold that can grow on moist peanuts, pecans, corn and other foodstuffs?

aflatoxin

What are the foodborne bacterial intoxications?

staphylococcal intoxication: an enterotoxin produced by S. aureus, botulism: a neurotoxin produced by clostridium botulinum

The D-value as a function of temperature has what type of relationship?

linear

What is the temperature and time range for commercial sterilization?

116-121 C (240-250 F) for 50-90 min

What is the value for the increase in temperature required to decrease the D value by 10 (or one log cycle reduction)?

z-value

Flashcard Info

Food safety toxicology and microbiology