Foodborne pathogens Flashcards
what is the source of majority of foodborne disease?
food service- 80%
what is a foodborne intoxication?
toxin that is produced DURING the growth of bacteria in food
how does the toxin behave in food intoxications?
the toxin is independent of the presence of live bacteria
-toxin can be heat resistant and present even when bacteria is dead
why can toxin produced from bacteria producing food intoxications be very dangerous?
Because the sensory properties of food may be unaltered
why must risk of C. botulinum be as small as possible?
it is very deadly and preys on animals of any size
what led to the recall of carrot juice in Ottawa 2007?
recall was due to the lack of controls put in place during processing
-the low pH and aerobic environment of the sealed bottle, this made it a prime environment for C. botulinum growth
-no presence was tested but there is still a risk
what are the 3 kinds of botulism?
foodborne, infant and wound
how is infection with C. botulinum treated?
1) establishing a clear airway and aiding in breathing (mechanical ventilation)
2) Antitoxin
How is C. botulinum detected?
1) Culture methods test presence
2) Mouse bioassay
3) ELISA
4) Lateral flow immunoprecipitation devices
how do group 1 and 2 C. botulinum organisms differ in their ability to hydrolyze proteins, grow in the fridge and spore resistance?
Type 1: hydrolyze proteins, don’t grow in the fridge and have a spore resistance of D120 up to 1 minute
Type 2: don’t hydrolyze proteins, grow in the fridge and have a D90 for 3 minutes
hydrolization provides an indication of contamination
what is LD50? what is its value for botox?
lethal death 50, the amount of drug required to cause death in 50% of a test population
-0.00001
what is considered commercial sterility?
D12- designed to kill 12 log CFU
-treatment will result in a safe product
what is used as a control measure as a “surrogate organism” to control C. botulinum in food production? why?
D 121 degrees celsius for C. sporogenes for 1 minute
-it is more heat resistant than C. botulinum and some strains have D values that are comparable to this
what is the main C. botulinum group in seafood? what precautions are taken?
group 2 (type E toxin)
-fermented seafood (pH is not lowered)
-pasteurize 6D at 90°C for 10 minutes
