Sterilization and Disinfection
Microbiology
Sterilization and Disinfection
Definitions
Sterilization
Removal or destruction of all microbial life forms
Heat
Ethylene oxide (Gas)
Filtration
Commercial sterilization
Heat required would degrade food
Heated to kill Clostridium botulinum endospores
Non-pathogens may survive, but do not grow
Commercial sterilization
Heat required would degrade food
Heated to kill Clostridium botulinum endospores
Non-pathogens may survive
Do not grow at storage temperature
Could grow if incubated
Disinfection
Destroying harmful microorganisms
Implies inert surface or substance
Destruction of vegetative (non – endospre forming) pathogens
Forms
Chemicals
Ultraviolet radiation
Boiling water or steam
Antisepsis
Disinfection directed towards living tissue
Antiseptic
Listerine
Antiseptic in the mouth or cut
Disinfectant on the table
Chemical must not be caustic to tissue
Degerming (degermation)
Mechanical removal of microbes in a limited area
Alcohol swab
Sanitization
Lower microbe counts to safe public health levels
Minimize chance of disease spread
Bar glasses
– cide
Causes death of organism
Homicide
Virucide
Fungicide
Germicide
May not kill endospores
Bactericidal
Penicillin
– stat or –stasis
Inhibit growth and multiplication of microorganism
Bacteristatic antibiotics
Tetracycline
Sepsis
Indicates bacterial contamination
Septic tanks
Septicemia
Asepsis
Absence of significant contamination
Aseptic technique
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