Foodborne Zoonoses Flashcards
Preferred bacterial growth conditions
Ph >4 (=7) Aw >0.9 redox potential Nutrient composition Anti microbial constituents Biological structures Temp varies Gaseous atmosphere Competition
Preferred yeast conditions
Ph 3-10
Aw >0.8
Sources of meat contamination
Animal hide Knife Gi tract Hands & tools Cutting/mincing operations Lymph nodes Packaging material Equipment
Spoilage Organisms
G- bacilli Spore forming G+ bacteria Other G + bacteria Moulds Yeast
What is campylobacter
A GI pathogen causing human enteric illness, found in raw poultry, pigs, cattle & sheep
Combatting campylobacter
Inactivated by heat/pasteurisation/cooking. Can’t grow below 30 degrees but survives as low as 4
Exposure to air/oxidative stress
Osmotic stress
What is camplyobacteriosis
Varies symptoms & length
Diarrhoea (blood stained), abd pain, fever, head/back ache, aching limbs, nausea
Control campylobacter
Hygiene measures Clean water Bio security Good SH & processing practice Correct cooking &a storage of raw meat
What is L monocytogenes
G+ anaerobe
Resistant to many unfavourable enviro conditions
Comes from many meat/fish/animal product sources and raw veg
Can multiply at fridge temps
Listerosis in humans
Often affects immunosuppressed people
Affects pregnant uterus, CNS, bloodstream
Can have many manifestations
Control of L mono
Re formulate product so it doesn’t support growth
Temp control
Shorten refridge period
Hygiene practices
What is E. coli
G - anearobe Found in lower I tract of mammals & birds Mild diarrhoea- very severe Can't tell in animals, super shedders Major outbreaks link to meat products Cattle
E. coli spread
Water Wild animals/birds Hide contamination Faecal contam Processing
Control of E. coli
Good management as colonisation of gut affected by this
Reduce VTEC exposure
Exclude VTEC from herd
Food borne Viruses
Contam at all food chain stages
Don’t contam food, just use as a vehicle for transfer
Recycling of human viruses back to human
