Food microbiology exam queries and
answers graded A+
Which two foods have been implicated in the most FBIs? - ANS✅✅Fresh food (fruit, vegies, and
nuts) and meats
The leading cause of food borne illness deaths is due to??? - ANS✅✅Salmonella
VBNC bacteria, if present, usually grow quite weakly or slowly. They are a major concern for? -
ANS✅✅Unidentified cause food borne illness
The acronym VBNC stands for... - ANS✅✅viable but non-culturable
ATP bioluminescence can be used to determine if a surface is contaminated by? - ANS✅✅yeasts
and molds,plant cells,animal cells, and bacteria
T or F RLU's or relative light units are measurements of ATP presence that can be compared across
surfaces, from different environments or even different manufacturing plants. - ANS✅✅False
DNA hybridization is - ANS✅✅a method used to directly detect bacteria using a target DNA probe
A common method used by Epidemiologists to tie together multi-state pathogen outbreaks is... -
ANS✅✅Pulsed field gel electrophoresis
The ELISA rapid testing system can be used to detect? - ANS✅✅bacterial toxins, viral
proteins ,bacterial enzymes , and chemical food hazards like histamine or allergens
Chemicals that have been approved for use or otherwise approved based on historical safety are
called ________ by the US FDA. (spelling counts) - ANS✅✅GRAS
A food preservation mechanism that inhibits or slows microbial growth is called a
____________________ and a food preservation mechanism that prevents or eliminates microbial
growth is called a____________________ . Answers are one word only. - ANS✅✅hurdle, barrier
, Sodium benzoate as a food preservative is - ANS✅✅Used for low pH foods e.g. < 4, used to inhibit
yeasts and molds, and Used at 0.1% or less w/w
Potassium sorbate as a food preservative is - ANS✅✅used at pH values of 4-6
Sulphite is highly reactive with ATP. It is used as an antimicrobial targeting... - ANS✅✅some molds,
bacteria and some yeasts
Ethylene oxide or propylene oxide can be used as antimicrobial and spore destroying fumigants to
effectively sterilize... - ANS✅✅Dry spices
__________________ is a food preservative used in cured meats to prevent C. botulinum growth
and __________ is a food preservative used in mostly ready to eat meats to prevent L.
monocytogenes growth. - ANS✅✅nitrite, lactate
A food chemical or ingredient that binds water in that food thus lowering the Aw is called a... -
ANS✅✅humectant
Eugenol or allicin are examples of.. - ANS✅✅Plant based antimicrobials
Which microorganisms will grow in an aerobic environment? - ANS✅✅pseudomonas, listeria and
bacillus
Obligate (as in obligate aerobe or obligate anaerobe) means? - ANS✅✅By necessity (required)
Which answers (one or more) are considered reduced oxygen packaging? - ANS✅✅60% carbon
dioxide and 100% nitrogen
Which gas has an antimicrobial effect? - ANS✅✅CO2
Pork that has been modified atmosphere packaged in N and CO2 would be expected to? -
ANS✅✅Last longer (not spoil) in CO2 than in N
answers graded A+
Which two foods have been implicated in the most FBIs? - ANS✅✅Fresh food (fruit, vegies, and
nuts) and meats
The leading cause of food borne illness deaths is due to??? - ANS✅✅Salmonella
VBNC bacteria, if present, usually grow quite weakly or slowly. They are a major concern for? -
ANS✅✅Unidentified cause food borne illness
The acronym VBNC stands for... - ANS✅✅viable but non-culturable
ATP bioluminescence can be used to determine if a surface is contaminated by? - ANS✅✅yeasts
and molds,plant cells,animal cells, and bacteria
T or F RLU's or relative light units are measurements of ATP presence that can be compared across
surfaces, from different environments or even different manufacturing plants. - ANS✅✅False
DNA hybridization is - ANS✅✅a method used to directly detect bacteria using a target DNA probe
A common method used by Epidemiologists to tie together multi-state pathogen outbreaks is... -
ANS✅✅Pulsed field gel electrophoresis
The ELISA rapid testing system can be used to detect? - ANS✅✅bacterial toxins, viral
proteins ,bacterial enzymes , and chemical food hazards like histamine or allergens
Chemicals that have been approved for use or otherwise approved based on historical safety are
called ________ by the US FDA. (spelling counts) - ANS✅✅GRAS
A food preservation mechanism that inhibits or slows microbial growth is called a
____________________ and a food preservation mechanism that prevents or eliminates microbial
growth is called a____________________ . Answers are one word only. - ANS✅✅hurdle, barrier
, Sodium benzoate as a food preservative is - ANS✅✅Used for low pH foods e.g. < 4, used to inhibit
yeasts and molds, and Used at 0.1% or less w/w
Potassium sorbate as a food preservative is - ANS✅✅used at pH values of 4-6
Sulphite is highly reactive with ATP. It is used as an antimicrobial targeting... - ANS✅✅some molds,
bacteria and some yeasts
Ethylene oxide or propylene oxide can be used as antimicrobial and spore destroying fumigants to
effectively sterilize... - ANS✅✅Dry spices
__________________ is a food preservative used in cured meats to prevent C. botulinum growth
and __________ is a food preservative used in mostly ready to eat meats to prevent L.
monocytogenes growth. - ANS✅✅nitrite, lactate
A food chemical or ingredient that binds water in that food thus lowering the Aw is called a... -
ANS✅✅humectant
Eugenol or allicin are examples of.. - ANS✅✅Plant based antimicrobials
Which microorganisms will grow in an aerobic environment? - ANS✅✅pseudomonas, listeria and
bacillus
Obligate (as in obligate aerobe or obligate anaerobe) means? - ANS✅✅By necessity (required)
Which answers (one or more) are considered reduced oxygen packaging? - ANS✅✅60% carbon
dioxide and 100% nitrogen
Which gas has an antimicrobial effect? - ANS✅✅CO2
Pork that has been modified atmosphere packaged in N and CO2 would be expected to? -
ANS✅✅Last longer (not spoil) in CO2 than in N
