FOOD
MICROBIOLOGY
Dr.SalehhuddinHamdan
Introduc)on
PartOne
HISTORYOFFOODMICROBIOLOGY
Food Microbiology
ABriefHistory
EarlyFoodPreserva)on
900ADFoodPoisoningRecognized
1795AppertDevelopedCanning
18541864FOODMICROBIOLOGYBECOMESA
SCIENCE
LouisPasteur
FoodBorneIllness
ERSEs)mates
$6.9Billion/YearCostofFBI
CDCEs)mates
76MillionCasesofFBIAnnually
325,000Hospitaliza)ons
5,000Deaths
WhyStudyFoodMicrobiology?
ProvideClean,Safe,HealthfulFoodto
Consumer
FoodPermitsGrowth
ControlofMicrobialGrowth
PreventFoodSpoilage
PreventFoodborneIllnesses
FoodPreserva)onandProduc)on
Microorganisms
Microorganisms are organisms that are too small to
be seen with the unaided eye.
Germ refers to a rapidly growing cell.
Benecial
Environment
Decomposi)on
Diges)on
Photosynthesis
Industry
Foodprocesses
Gene)cEngineering
Pathogenic
Food
Health
Microbialapplica)on
Decomposeorganicwaste
Areproducersintheecosystemby
photosynthesis
Produceindustrialchemicalssuchasethanol
andacetone
Producefermentedfoodssuchasvinegar,
cheese,andbread
Classica)onofOrganisms
3Domains
5Kingdoms
Prokaryo)c
Monera(bacteria)
Eukaryo)c
Pro)sta
Fungi
Plantae
Animaliae
Binomialnomenclature
Carolus Linnaeus
Genus
species
DomainArchaea
Noknownhuman
pathogens
Cellwallslack
pep)doglycan
ExtremeEnvironmental
Habitats
Methanogens
Halophiles
Thermophiles
DomainBacteria
Unicellular
VariousShapes
Cellwallshave
pep)doglycan
Binaryssion
Benecialvs.pathogenic
DomainEukarya
Eukarya
Fungi
Unicellular
Yeasts
Protista
Multicellular
Molds
Mushrooms
Protozoa:
Free living
Parasitic
Plants
Algae
Unicellular
Colonial
Simple Multi-celled
Animals
Viruses
Acellular
NucleicAcid
DNA
RNA
Envelope
Classica)on
Func)on
Inertoutsidehost
GoldenAgeofMicrobiology
Late1800searly1900s
Ques)onsandTheories
Developed
MicrobialSource
MicrobialProcesses
Diseasesource
Diseasepreven)on
AreasofStudy
Bacteriology
Immunology
Virology
Epidemiology
Chemotherapy
EarlyDevelopments
RobertHooke
CellTheory
Earlymicroscope
AntoniLeeuwenhoek
Improvedmicroscope
Microbesviewed
LouisPasteur
GermTheoryofDisease
Similardisease
symptoms
Germ=pathogen
Fermenta)on
Pasteuriza)on
FatherofMicrobiology
JosephLister
Asep)cTechnique
SurgicalSiteprepwith
phenol
Con)nuedHandwashing,
aspreviously
demonstratedby
Semmelweis
RobertKoch
SimpleStaintechnique
SolidgrowthMedia
Asep)clabtechniques
IsolatedBacteriaascausa)ve
agentsfor
Anthrax
TB
Cholera
KochsPostulates
Seriesofexperimental
stepstoshowthatspecic
organismcausesaspecic
disease
OriginalKochsPostulates
That the organism could be discoverable in every instance of the
disease;
That, extracted from the body, the germ could be produced in a
pure culture, maintainable over several microbial generations.
That the disease could be reproduced in experimental animals
through a pure culture removed by numerous generations from the
organisms initially isolated;
That the organism could he retrieved from the inoculated animal
and cultured anew.
EdwardJenner
Vaccina)on
Cowpoxscrapings
Smallpox
Immunologyeld
JohnSnow
CholeraPreven)on
FatherofEpidemiology
Firsttouseanesthesia
(ether)duringsurgery
FlorenceNigh)ngale
Nursingcare
Hygeine
Improvednursetraining
Chris)anGram
Dieren)alStainingofcell
wallsusingvariousdyes
Gramposi)ve
purple
Gramnega)ve
red
PaulEhrlich
Chemotherapeu)cAgents
MagicBulletTreatment
Syphilis
Trypanosome
EarlyAcidFaststaining
techniquesforTB
ImmunologicalStudieson
an)sera
Tumortransforma)on
research
AlexanderFlemming
An)bio)cpenicillin
Lysosomesecre)onby
)ssues
Developed)tra)on
methodsforanalyzing
bodyuids
MicrobesinHumanDiseases
NormalFlora
Inoronbody
Benecial
Normalhostdefensesprotect
Infec)ousDiseases
Loca)on
Virulencefactors
Microbelifecyclecausespathology
Hostdefenses
CHARACTERISTICOF
MICROORGANISMINFOOD
Food Microbiology
Microorganisms
Figure 1.1
KnowledgeofMicroorganisms
Allowshumansto
Preventfoodspoilage
Preventdiseaseoccurrence
Ledtoasep)ctechniquestoprevent
contamina)oninmedicineandin
microbiologylaboratories.
NamingandClassifying
Microorganisms
Linnaeusestablishedthesystemofscien)c
nomenclature.
Eachorganismhastwonames:thegenusand
specicepithet.
Scien)cNames
Areitalicizedorunderlined.Thegenusis
capitalizedandthespecicepithetislower
case.
AreLa)nizedandusedworldwide.
Maybedescrip)veorhonorascien)st.
Scien)cNames
Staphylococcusaureus
Describestheclusteredarrangementofthecells
(staphylo)andthegoldencolorofthecolonies
(aur).
Scien)cNames
Escherichiacoli
Honorsthediscoverer,TheodorEscherich,and
describesthebacteriumshabitatthelarge
intes)neorcolon.
Scien)cNames
Aoertherstuse,scien)cnamesmaybe
abbreviatedwiththerstleperofthegenus
andthespecicepithet:
StaphylococcusaureusandEscherichiacoliare
foundinthehumanbody.S.aureusisonskinand
E.coliinthelargeintes)ne.
Classica)onofMicroorganisms
Threedomains
Bacteria
Archaea
Eukarya
Pro)sts
Fungi
Plants
Animals
Bacteria
Prokaryotes
Pep)doglycancellwalls
Binaryssion
Forenergy,useorganic
chemicals,inorganic
chemicals,or
photosynthesis
Figure 1.1a
Bacteriacocci
Bacteriabacilli
Archaea
Prokaryo)c
Lackpep)doglycan
Liveinextremeenvironments
Include
Methanogens
Extremehalophiles
Extremethermophiles
Figure 4.5b
Fungi
Eukaryotes
Chi)ncellwalls
Useorganicchemicalsforenergy.
Moldsandmushroomsare
mul)cellularconsis)ngofmasses
ofmycelia,whicharecomposed
oflamentscalledhyphae.
Yeastsareunicellular.
Figure 1.1b
Mold
Mushroomediblereproduc)vestructure
Photos from kjbeaths photostream
Yeast
www.scientist.live.com
Protozoa
Eukaryotes
Absorboringest
organicchemicals
Maybemo)levia
pseudopods,cilia,
oragella
Figure 1.1c
Algae
Eukaryotes
Cellulosecellwalls
Usephotosynthesisfor
energy
Producemolecular
oxygenandorganic
compounds
Figure 1.1d
Viruses
Acellular
ConsistofDNAorRNAcore
Coreissurroundedbyaprotein
coat.
Coatmaybeenclosedinalipid
envelope.
Viruses are replicated only when they are in a living host cell.
Many are transmitted via contaminated food or water, and
many pass directly from human to human contact
Figure 1.1e
Rotavirus
http://www.carlgoodman.co.uk/scientific/scientific/A-microscopic-01.jpg
Mul)cellularAnimalParasites
Eukaryote
Mul)cellularanimals
Parasi)catwormsandroundwormsarecalled
helminths.
Microscopicstagesinlifecycles.
SOURCEOFMICROORGANISMIN
FOOD
Food Microbiology
MicroorganismsFoundinFood
A.Grains
1. Importanceofdrying
2. Microbialspoilers
B.Fruitsandvegetables
1. Commensals
2. Microbialspoilers
C.Meatsandpoultry
1.
2.
3.
4.
Meatinspec)on
Agingofmeat
Groundmeats
Poultryandeggs
D.Fishandshellsh
1. Freshsh
2. Shellsh
3. Crustaceans
E.Milk
1. Milkhandling
2. Milkcontaminants
3. Milksouringagents
F.Otherediblesubstances
1.
2.
3.
4.
5.
Sugarandsugarproducts
Maplesyrupandhoney
Spices
Condiments
Beverages
