food microbiology - neha cert – produced in the food food microbiology examples of toxins: some...

Food MicrobiologyCopyright 2008 1

FOOD FOOD MICROBIOLOGYMICROBIOLOGY

Judith Espinoza, MPHJudith Espinoza, MPHEpidemiologistEpidemiologist

City of AlbuquerqueCity of AlbuquerqueOctober 2008October 2008

OverviewOverviewTypes of Pathogens Types of Pathogens Basic TerminologyBasic TerminologyCommon Microorganism Associated Common Microorganism Associated with Foodborne Illnesswith Foodborne IllnessCategories of Microorganisms byCategories of Microorganisms by

Symptoms, Possible Causes, Spore Symptoms, Possible Causes, Spore Forms, Toxin ProducersForms, Toxin Producers

Food Microbiology

Types of PathogensTypes of Pathogens

Food Microbiology


PrionsPrionsSmallest Smallest Protein Protein Known to cause variant CreutzfeldtKnown to cause variant Creutzfeldt--Jakob disease (Jakob disease (vCJDvCJD) (Mad Cow)) (Mad Cow)Long incubation Long incubation

Food Microbiology

VirusesViruses

Smaller than bacteriaSmaller than bacteriaNo cell walls, membrane or nucleusNo cell walls, membrane or nucleusCan NOT reproduce outside a host Can NOT reproduce outside a host (Require a living cell to reproduce) (Require a living cell to reproduce) Can survive outside a hostCan survive outside a host

Food Microbiology

BacteriaBacteriaLargest number of living organisms on Largest number of living organisms on earth.earth.Forms Forms ––

round (round (StaphStaph), ), rod (rod (SalmonellaSalmonella), ), spiral (spiral (CampylobacterCampylobacter) ) comma shaped comma shaped VibrioVibrio

Reproduce by binary fissionReproduce by binary fissionMany pathogenic bacteria are facultativeMany pathogenic bacteria are facultative

Food Microbiology


BacteriaBacteriaAll bacteria have vegetative state All bacteria have vegetative state (reproduce and generate waste)(reproduce and generate waste)Some form sporesSome form spores

Bacilli (Bacilli (Bacillus cereusBacillus cereus))ClostridaClostrida ((Clostridium Clostridium perfringensperfringens, , Clostridium Clostridium botulinumbotulinum) )

SporeSpore--forming bacteria generally are forming bacteria generally are found in animal products or foods like found in animal products or foods like vegetables that are grown in the soil. vegetables that are grown in the soil.

Food Microbiology

Molds Molds Mycology (Mycology (MycoMyco=fungus)=fungus)

Single celled or Single celled or MulticellularMulticellularWide pH rangeWide pH rangeGrow best in damp dark environmentsGrow best in damp dark environmentsMusty smellMusty smellSome produce Some produce mycotoxinsmycotoxins

AflatoxinAflatoxin mold growing on nuts, corn, mold growing on nuts, corn, wheat (found in peanut butter) wheat (found in peanut butter)

Some mold is beneficialSome mold is beneficialFood Microbiology

Yeast Yeast (Part of Mycology and Fungi)(Part of Mycology and Fungi)

Single celled organisms that convert food Single celled organisms that convert food to alcohol and sugar by fermentation.to alcohol and sugar by fermentation.Need moisture, food in the form of sugar Need moisture, food in the form of sugar or starch, and warmth.or starch, and warmth.Yeasts are responsible for few illnesses in Yeasts are responsible for few illnesses in humans and there is no evidence that they humans and there is no evidence that they are transmitted by food. are transmitted by food.

Food Microbiology


ParasitesParasites

Must live on or inside a living organism to Must live on or inside a living organism to reproduce, can survive without a hostreproduce, can survive without a hostUsually bigger than bacteria and multiUsually bigger than bacteria and multi--cellular cellular FDA two methods for destroying parasites FDA two methods for destroying parasites in raw animal food productsin raw animal food products

FreezingFreezingCookingCooking

Food Microbiology

Basic TerminologyBasic TerminologyOxygen RequirementOxygen RequirementTemperature TermsTemperature Terms

Types of ToxinTypes of ToxinBacteria GrowthBacteria Growth

Foodborne IllnessFoodborne Illness

Food Microbiology

AerobeAerobeAn organism, especially a An organism, especially a

bacterium, requiring oxygen to bacterium, requiring oxygen to live. live.

Food Microbiology


AnaerobeAnaerobe(An- before a word means without)

An organism, especially a bacterium, An organism, especially a bacterium, NOT NOT requiring oxygen to live. requiring oxygen to live.

Examples - Clostridium (botulism and canned goods)

Food Microbiology

FacultativeFacultativeAble to grow either with or Able to grow either with or

without the presence of free without the presence of free oxygen.oxygen.

Most foodborne disease-causing microorganisms are facultative anaerobes

Food Microbiology

MicroaerophilicMicroaerophilicAerobic Bacteria that grow Aerobic Bacteria that grow

better under better under slightly reducedslightly reducedoxygen requirements.oxygen requirements.

Example - Campylobacter

Food Microbiology


••MesophileMesophile--a a microoganismmicrooganism that grows that grows best at moderate temperatures with best at moderate temperatures with optimum growth between 77optimum growth between 77˚̊ F and F and 113 113 ˚̊ F (25 F (25 ˚̊C C --45 45 ˚̊C)C)••PsychrophilePsychrophile -a microorganism capable of growing at refrigerated or room temperatures but grow best at cold temperatures. Optimum 47 ˚ F -68 ˚ F (5 ˚C -20 ˚C ) ••ThermophileThermophile - a microorganism that grows best at temperatures above 110 ˚ F (43 ˚ FC)

Food Microbiology

Examples of toxins:Examples of toxins:Some types of toxins can be used to Some types of toxins can be used to

describe where they are produced in the describe where they are produced in the body or in the food. body or in the food.

EndotoxinsEndotoxins –– produced in the bodyproduced in the bodyExotoxinsExotoxins –– produced in the foodproduced in the food

Food Microbiology

Examples of toxins:Examples of toxins:Some types of toxins can be used to Some types of toxins can be used to describe where in the body they affect.describe where in the body they affect.

EnterotoxinsEnterotoxins-- affect the small intestineaffect the small intestineNeurotoxins Neurotoxins –– affect the central nervous affect the central nervous systemsystem

Food Microbiology


Examples of toxins:Examples of toxins:Other types of toxins can describe what Other types of toxins can describe what

type of organism produces it. type of organism produces it.

MycotoxinsMycotoxins –– produced by moldsproduced by moldsShigaShiga--toxins toxins –– particular type of toxin particular type of toxin produced by bacteria produced by bacteria E. coli & E. coli & ShigellaShigellaCiguatoxinCiguatoxin –– produced by algaeproduced by algae

ScombrotoxinScombrotoxin –– histamine poisoning (fish) histamine poisoning (fish) Food Microbiology

ColonyColonyA cluster of microorganisms that is A cluster of microorganisms that is growing within, or on the surface growing within, or on the surface

of a nutrient medium and that of a nutrient medium and that contains millions of cells. contains millions of cells.

Food Microbiology

Binary FissionBinary Fission

The process by which bacteria The process by which bacteria reproduce (nonsexual reproduce (nonsexual

reproduction) dividing in two under reproduction) dividing in two under ideal conditions ideal conditions

Food Microbiology


Bacterial GrowthBacterial Growth

Lag Lag –– bacteria bacteria exhibit little or no exhibit little or no growthgrowthLog Bacteria growth Log Bacteria growth is very rapidis very rapidStationary Stationary –– number number of new bacteria = of new bacteria = the number dyingthe number dyingDecline Decline –– rapid die rapid die offoff..

0

5

10

15

20

25

Lag

Log Decline

Stationary

Food Microbiology

Infective DoseInfective DoseThe number of microorganisms The number of microorganisms required to cause a foodborne required to cause a foodborne

illness in one person illness in one person

Shigella spp. as few as 10 cells depending on age and condition of host. Listeria monocytogenes is unknown, but in susceptible persons, fewer than 1,000 total organisms may cause disease.

Food Microbiology

Types of Foodborne Types of Foodborne Illnesses Illnesses Three categoriesThree categories

Food Microbiology


InfectionInfection --caused by eating food that caused by eating food that contains living diseasecontains living disease--causing causing microorganismsmicroorganisms

IntoxicationIntoxication --caused by eating food caused by eating food that contains a harmful chemical or that contains a harmful chemical or toxin produced by bacteria or other toxin produced by bacteria or other sourcesource

ToxinToxin--Mediated InfectionMediated Infection --caused by caused by eating food that contains harmful eating food that contains harmful microbes that will produce toxin once microbes that will produce toxin once inside the body.inside the body.

Food Microbiology

MicroorganismsMicroorganismsSome of the most common Some of the most common organism that cause foodborne organism that cause foodborne illness illness

BacteriaBacteriaVirusesVirusesParasitesParasites

Food Microbiology

Gram positive or gram negativeGram positive or gram negativerefers to how bacteria appear under a refers to how bacteria appear under a microscope after beginning stained.microscope after beginning stained.

Food Microbiology


Common Foodborne Common Foodborne Pathogens by Gram Stain TypePathogens by Gram Stain Type

Gram PositiveGram PositiveBacillus cereusBacillus cereusClostridium Clostridium perfringensperfringensClostridium Clostridium botulinumbotulinumListeriaListeria

monocytogenesmonocytogenesStaphylococcus Staphylococcus aureusaureus

Gram NegativeGram NegativeCampylobacter Campylobacter jejunijejuniShiga toxin Shiga toxin ––producing E. coliproducing E. coliSalmonella Salmonella sppspp..ShigellaShigella sppspp..VibrioVibrio sppspp..

Food Microbiology

Foodborne Foodborne illness(esillness(es))IntoxicationIntoxication (vomiting {(vomiting {exotoxinexotoxin})})ToxinToxin--Mediated InfectionMediated Infection (diarrhea (diarrhea {{enterotoxinenterotoxin})})

Gram Positive rod (soil bacteria)Gram Positive rod (soil bacteria)Spore former (spores heat resistant)Spore former (spores heat resistant)Facultative Facultative

Bacillus cereusBacillus cereus

Food Microbiology

Food borne illness Food borne illness –– toxintoxin--mediated mediated infection (diarrhea {infection (diarrhea {enterotoxinenterotoxin})})Anaerobes (require very little oxygen)Anaerobes (require very little oxygen)Usually due to improperly cooling food so Usually due to improperly cooling food so that spores are able to return to vegetative that spores are able to return to vegetative state.state.

Also causes gangrene in wound or skin Also causes gangrene in wound or skin infections unrelated to food.infections unrelated to food.

Clostridium Clostridium perfringensperfringens

Food Microbiology


Clostridium Clostridium botulinumbotulinum•Food borne illness – intoxication –symptoms are neurological and is one of the deadliest biological toxins known to man (dizziness, double vision, trouble breathing . . .){neurotoxin}

•Anaerobes (require very little oxygen)

•Usually due to improperly cooling food so that spores are able to return to vegetative state.

Food Microbiology

Foodborne illness Foodborne illness infectioninfection-- an invasive organism. an invasive organism.

toxintoxin--mediated infection mediated infection -- pathogenic pathogenic mechanisms are still not completely mechanisms are still not completely understood, but it does produce a heatunderstood, but it does produce a heat--labile labile toxin that may cause diarrhea. toxin that may cause diarrhea.

Causes very watery diarrhea and/or Causes very watery diarrhea and/or bloody bloody diarrheadiarrhea

Campylobacter Campylobacter jejunijejuni

Food Microbiology

Gram negative curvy rodGram negative curvy rodFound in many of the same foods & has Found in many of the same foods & has some of the same symptoms as some of the same symptoms as SalmonellaSalmonella butbut is is microaerophilicmicroaerophilic and and had a differenthad a different onset time (2onset time (2--5 days) 5 days) ..Relatively fragileRelatively fragile-- sensitive to environmental sensitive to environmental stresses (e.g., 21% oxygen, drying, heating, stresses (e.g., 21% oxygen, drying, heating, disinfectants, acidic conditions)disinfectants, acidic conditions)

Campylobacter Campylobacter jejunijejuni

Food Microbiology


Foodborne illnessFoodborne illnessInfectionInfectionToxinToxin--mediated infectionmediated infection (watery diarrhea (watery diarrhea ––bloody stools) {bloody stools) {enterotoxinenterotoxin}}

Gram negative rodGram negative rodE. coli E. coli –– normal flora in most mammals normal flora in most mammals (humans, cattle, dogs, cats, goats) but not (humans, cattle, dogs, cats, goats) but not all are pathogens and not all types all are pathogens and not all types produce toxins. produce toxins.

Shiga toxinShiga toxin--producing producing EscherichaEschericha colicoli

Food Microbiology

ListeriaListeria monocytogenesmonocytogenes, , sppsppFoodborne illness Foodborne illness –– infectioninfection

L. L. monocytogenesmonocytogenes may invade may invade the gastrointestinal epithelium.the gastrointestinal epithelium.

Can cause miscarriages Can cause miscarriages The overall mortality for meningitis The overall mortality for meningitis

may be as high as 70%; from may be as high as 70%; from septicemia 50%, from septicemia 50%, from perinatalperinatal/neonatal infections greater /neonatal infections greater than 80%. than 80%. In infections during pregnancy, the In infections during pregnancy, the

mother usually survives.mother usually survives.Food Microbiology

ListeriaListeria monocytogenesmonocytogenes, , sppspp

L. L. monocytogenesmonocytogenes is quite hardy and is quite hardy and resists to freezing, drying, and heat.resists to freezing, drying, and heat.Does not form sporesDoes not form spores

Can grow slowly in cold temperatures and Can grow slowly in cold temperatures and can survive in highcan survive in high--salt food.salt food.Foods Foods –– raw dairy products (also cold raw dairy products (also cold cuts) cuts)

Food Microbiology


Salmonella Salmonella sppspp..

Foodborne illness Foodborne illness –– mostly infectionmostly infectionSimilar in many ways to Campy. Similar in many ways to Campy. Very larger group of bacteriaVery larger group of bacteriaCause of disease Cause of disease ---- Penetration and Penetration and passage of Salmonella organisms from gut passage of Salmonella organisms from gut lumen into epithelium of small intestine lumen into epithelium of small intestine where inflammation occurs; there is where inflammation occurs; there is evidence that an evidence that an enterotoxinenterotoxin may be may be produced. produced.

Food Microbiology

ShigellaShigella sppspp..Foodborne illness Foodborne illness

InfectionInfectionToxinToxin--mediated infectionmediated infection

The disease is caused when virulent The disease is caused when virulent ShigellaShigellaorganisms attach to, and penetrate, epithelial organisms attach to, and penetrate, epithelial cells of the intestinal mucosa. After invasion, cells of the intestinal mucosa. After invasion, they multiply they multiply intracellularlyintracellularly, and spread to , and spread to contiguous contiguous epithelealepitheleal cells resulting in tissue cells resulting in tissue destruction. Some strains produce destruction. Some strains produce enterotoxinenterotoxin (a Shiga toxin very much like the (a Shiga toxin very much like the E. coliE. coli).).Poor hygiene practices Poor hygiene practices Food Microbiology

Staphylococcus Staphylococcus aureusaureus, ,

Gram positive Gram positive coccicocciOne type of foodborne illness One type of foodborne illness ––intoxication (vomiting)intoxication (vomiting)Found in ready to eat food or preFound in ready to eat food or pre--cooked cooked food that are reheated.food that are reheated.ExotoxinExotoxin –– very heat stable very heat stable Very common skin bacteriaVery common skin bacteria

Food Microbiology


VibrioVibrio sppsppFoodborne illness Foodborne illness

infectioninfection--ToxinToxin--mediated infectionmediated infection -- caused by caused by ingesting the organisms, which attach to ingesting the organisms, which attach to the small intestine and produce the small intestine and produce cholera cholera toxintoxin ((enterotoxinenterotoxin))

Most commonly associated with water or Most commonly associated with water or food from the water.food from the water.Gram negative straight or curvy rod Gram negative straight or curvy rod Can cause very watery diarrheaCan cause very watery diarrhea

Food Microbiology

VirusesViruses

Hepatitis A, Norwalk virus, Hepatitis A, Norwalk virus, Rotavirus, Rotavirus,

Food Microbiology

Hepatitis A,Hepatitis A,Poor hygiene & raw seafoodPoor hygiene & raw seafoodJaundice (liver infection)Jaundice (liver infection)Long incubation period (10Long incubation period (10--50 50

days without showing symptoms)days without showing symptoms)Foods have been implicated in Foods have been implicated in

over 30 outbreaks since 1983 , over 30 outbreaks since 1983 , seafood, lettuce , frozen seafood, lettuce , frozen strawberries strawberries

Food Microbiology


Norwalk virusNorwalk virusQuick onset 2Quick onset 2--3 days3 daysContaminated waterContaminated waterIngestion of raw or insufficiently steamed Ingestion of raw or insufficiently steamed clams and oysters poses a high risk. clams and oysters poses a high risk. Other foods contaminated by ill food Other foods contaminated by ill food handlers. handlers. Ten well documented outbreaks caused Ten well documented outbreaks caused by Norwalk virus were reported in the by Norwalk virus were reported in the U.S., involving a variety of foods: fruits, U.S., involving a variety of foods: fruits, salads, eggs, clams, and bakery items. salads, eggs, clams, and bakery items.

Food Microbiology

RotavirusRotavirus

Quick onset 1Quick onset 1--3 days3 daysSymptoms often start with vomiting Symptoms often start with vomiting followed by 4followed by 4--8 days of diarrhea. 8 days of diarrhea. Temporary lactose intolerance may occur.Temporary lactose intolerance may occur.Contaminated water or PersonContaminated water or Person--toto--personpersonThe virus has not been isolated from any The virus has not been isolated from any food associated with an outbreak, and no food associated with an outbreak, and no satisfactory method is available for routine satisfactory method is available for routine analysis of food. analysis of food.

Food Microbiology

ParasitesParasitesAnisakisAnisakis sppspp., ., CycolsporaCycolspora

cayetanensiscayetanensis, Cryptosporidium , Cryptosporidium parvumparvumGiardiaGiardia lamblialamblia, , ToxoplasmaToxoplasma gondiigondii, ,

TrichinellaTrichinella spiralisspiralis

Food Microbiology


AnisakisAnisakis sppspp..Unsure onset 1 hr Unsure onset 1 hr –– 2 weeks2 weeksFrequently diagnosed when the affected Frequently diagnosed when the affected individual feels a tingling or tickling individual feels a tingling or tickling sensation in the throat and coughs up or sensation in the throat and coughs up or manually extracts a nematode manually extracts a nematode Fewer than 10 cases are diagnosed in the Fewer than 10 cases are diagnosed in the U.S. annually. However, it is suspected U.S. annually. However, it is suspected that many other cases go undetected. that many other cases go undetected. The disease is transmitted by raw, The disease is transmitted by raw, undercooked or insufficiently frozen fish undercooked or insufficiently frozen fish and shellfish, and its incidence is expected and shellfish, and its incidence is expected to increase with the increasing popularity to increase with the increasing popularity of sushi and sashimi bars. of sushi and sashimi bars. Food Microbiology

CycolsporaCycolspora cayetanensiscayetanensis~ 1 week onset~ 1 week onsetWater, berries, raw vegetablesWater, berries, raw vegetablesAct upon the small intestine resulting in Act upon the small intestine resulting in water diarrhea (explosive)water diarrhea (explosive)PersonPerson--toto--person, oral fecal routeperson, oral fecal routeCurrently little is known about this Currently little is known about this organism, although cases of organism, although cases of cyclosporiasiscyclosporiasis are being reported from are being reported from various countries with increasing various countries with increasing frequency. frequency.

Food Microbiology

Cryptosporidium Cryptosporidium parvumparvum

1 week1 weekContaminated waterContaminated waterSmall and resistant to chlorine,the Small and resistant to chlorine,the sporocystssporocysts are resistant to most chemical are resistant to most chemical disinfectants, but are susceptible to drying disinfectants, but are susceptible to drying and the ultraviolet portion of sunlight. and the ultraviolet portion of sunlight.

Food Microbiology


GiardiaGiardia lamblialambliaLast 1 to 2 weeks, but some chronic Last 1 to 2 weeks, but some chronic infections last months to years. infections last months to years. Contaminated waterContaminated waterBigger than cryptoBigger than cryptoInfectious Dose Infectious Dose -- Ingestion of one or more Ingestion of one or more cysts may cause disease.cysts may cause disease.Five outbreaks have been traced to food Five outbreaks have been traced to food contamination by infected food handlers, contamination by infected food handlers, and the possibility of infections from and the possibility of infections from contaminated vegetables that are eaten contaminated vegetables that are eaten raw cannot be excluded. raw cannot be excluded.

Food Microbiology

ToxoplasmaToxoplasma gondiigondiiToxoplasmosis is considered to be the Toxoplasmosis is considered to be the third leading cause of death attributed to third leading cause of death attributed to foodborne illness in the United States. foodborne illness in the United States. Women newly infected with Women newly infected with ToxoplasmaToxoplasmaduring pregnancy and anyone with a during pregnancy and anyone with a compromised immune system should be compromised immune system should be aware that toxoplasmosis can have severe aware that toxoplasmosis can have severe consequences for them.consequences for them.

Food Microbiology

ToxoplasmaToxoplasma gondiigondii

A parasite that causes a very severe A parasite that causes a very severe disease that can cause central nervous disease that can cause central nervous system disorders, such as mental system disorders, such as mental retardation and visual impairment in retardation and visual impairment in children. children. Sources:Sources: Raw or undercooked pork, Raw or undercooked pork, lamb, or venison and cat, rat, rodent, or lamb, or venison and cat, rat, rodent, or bird feces.bird feces.

Food Microbiology


TrichinellaTrichinella spiralisspiralisTrichinellosisTrichinellosis is caused by a parasite that is a is caused by a parasite that is a nematodes (roundworms).nematodes (roundworms).Rats and rodents are reservoirRats and rodents are reservoirCarnivorous/omnivorous animals, such as pigs Carnivorous/omnivorous animals, such as pigs or bears, feed on infected rodents or meat from or bears, feed on infected rodents or meat from other animals.other animals.Humans are accidentally infected when eating Humans are accidentally infected when eating improperly processed meat of these carnivorous improperly processed meat of these carnivorous animals (or eating food contaminated with such animals (or eating food contaminated with such meat). meat).

Food Microbiology

Specific ToxinSpecific Toxin

AflatoxinAflatoxin, , CiguatoxinCiguatoxin, , ScombrotoxinScombrotoxin

Food Microbiology

AflatoxinAflatoxinIntoxication Intoxication ––acute or chronicacute or chronicHepatocarcinogenHepatocarcinogen ((HepatoHepato = liver, = liver, CarcingoenCarcingoen= cancer causing= cancer causing) ) Produced by fungi (mold) Produced by fungi (mold) exotoxinexotoxinIn the United States, In the United States, aflatoxinsaflatoxins have been have been identified in corn and corn products, identified in corn and corn products, peanuts and peanut products, cottonseed, peanuts and peanut products, cottonseed, milk, and tree nuts such as Brazil nuts, milk, and tree nuts such as Brazil nuts, pecans, pistachio nuts, and walnuts. pecans, pistachio nuts, and walnuts.

Food Microbiology


CiguatoxinCiguatoxin

Produced by algae Produced by algae Caused by the consumption of subtropical Caused by the consumption of subtropical and tropical marine finfish which have and tropical marine finfish which have accumulated naturally occurring toxins accumulated naturally occurring toxins through their diet. through their diet. The relative frequency of ciguatera fish The relative frequency of ciguatera fish poisoning in the United States is not poisoning in the United States is not known. known.

Food Microbiology

CiguatoxinCiguatoxinInitial signs of poisoning occur within six Initial signs of poisoning occur within six hours after consumption of toxic fish and hours after consumption of toxic fish and include include perioralperioral numbness and tingling numbness and tingling ((paresthesiaparesthesia), which may spread to the ), which may spread to the extremities, nausea, vomiting, and extremities, nausea, vomiting, and diarrhea. diarrhea. Ciguatera poisoning is usually selfCiguatera poisoning is usually self--limiting, limiting, and signs of poisoning often subside and signs of poisoning often subside within several days from onset. within several days from onset.

Food Microbiology

ScombrotoxinScombrotoxin(also called Histamine Poisoning) (also called Histamine Poisoning)

Caused by the ingestion of foods that Caused by the ingestion of foods that contain high levels of contain high levels of histaminehistamine..Histamine and other amines are formed by Histamine and other amines are formed by certain bacteria during production certain bacteria during production -- such such as Swiss cheese, or by spoilage of foods as Swiss cheese, or by spoilage of foods such as fishery products, particularly tuna such as fishery products, particularly tuna or or mahimahi mahimahi. . Neither cooking, canning, or freezing Neither cooking, canning, or freezing reduces the toxic effect. reduces the toxic effect.

Food Microbiology


Categories Categories CharacteristicsCharacteristics

Symptoms,Symptoms,Possible SourcesPossible SourcesSpore FormersSpore Formers

Toxin Producers Toxin Producers

Food Microbiology

The two anaerobic bacteriaThe two anaerobic bacteria

Clostridium Clostridium perfringensperfringensClostridium Clostridium botulinumbotulinum

Food Microbiology

The bacteria that produce The bacteria that produce toxin in the food (toxin in the food (exotoxinexotoxin))

B. cereusB. cereusC. C. botulinumbotulinum –– only neurotoxinonly neurotoxinStaphStaph. . aureusaureus

Food Microbiology


Poor HygienePoor Hygiene

All the viruses All the viruses –– HepHep A, A, NoroNoro and and RotoRotoShigellaShigella sppspp..StaphStaph. . aureusaureusVibrioVibrio sppsppE. coliE. coliSalmonella Salmonella sppspp..

Food Microbiology

Contaminated waterContaminated water

All the viruses All the viruses –– HepHep A, A, NoroNoro and and RotoRotoSome parasites Some parasites –– CyclosporaCyclospora, , Cryptosporidium, Cryptosporidium, GiardiaGiardiaVibrioVibrio sppspp

Food Microbiology

The bacteria that are most The bacteria that are most likely to produce bloody likely to produce bloody

diarrheadiarrhea

Campylobacter Campylobacter Shiga toxin producing Shiga toxin producing E. coli E. coli ShigellaShigella

Food Microbiology


Which bacteria can produce Which bacteria can produce spores?spores?

B. cereusB. cereusClostridium Clostridium perfringensperfringensClostridium Clostridium botulinumbotulinum

Food Microbiology

SummarySummaryCategories of Microorganisms byCategories of Microorganisms by

Symptoms, Possible Causes, Spore Symptoms, Possible Causes, Spore Forms, Toxin ProducersForms, Toxin Producers

Common Microorganism Associated Common Microorganism Associated with Foodborne Illnesswith Foodborne IllnessBasic TerminologyBasic TerminologyTypes of Pathogens Types of Pathogens

Food Microbiology

ReferencesReferencesModern Food MicrobiologyModern Food Microbiology, 6, 6thth edition, 2000 edition, 2000 James M. JayJames M. Jayhttp://www.microbeworld.org/microbes/virus/http://www.microbeworld.org/microbes/virus/http://www.doctorfungus.org/mycoses/index.hhttp://www.doctorfungus.org/mycoses/index.htmtmhttp://www.foodsafety.gov/~mow/intro.htmlhttp://www.foodsafety.gov/~mow/intro.htmlhttp://http://www.microbionet.com.au/salmonella.htwww.microbionet.com.au/salmonella.htmm

Food Microbiology

food microbiology - neha cert – produced in the food food microbiology examples of toxins: some...

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