Food Science 2017 Flashcards
What is the lag phase in regards to bacterial growth phases?
Most important phase in bacterial growth - when bacteria is at its slowest growing point on exponential scale
goal of food preservation is to extend lag phase as long as possible
What is the log phase in regards to bacterial growth phases?
Exponential growth of bacteria
What is the stationary phase in regards to bacterial growth phases?
environmental conditions and food may become restrictive, causing leveling of bacterial growth
What is the deathphase in regards to bacterial growth phases?
bacteria start accumulating waste products and toxins that kill each other
What does the F stand for in FATTOM?
food - bacteria require nutrients such as proteins and carbonhydrates to reproduce
What does the A stand for in FATTOM?
acidity - pH: most microorganisms grow best at 4.6-7.0 pH
Acidic foods <4.6pH are considered outside of the potentially hazardous zone
What does the first T stand for in FATTOM?
time - right conditions bacteria reproduce every 15-30 mins
What does the second T stand for in FATTOM?
temperature - danger zone for bacterial growth is 41-135 degrees F
What does the O stand for in FATTOM?
oxygen - bacteria grow in aerobic and anaerobic conditions
What does the M stand for in FATTOM?
moisture - Aw = water activity
bacteria require water to survive
Aw 0.85 (85%) or higher ideal for bacterial growth
What does sous vide stand for?
“Excluding air from the product”
What is “reduced-oxygen packaging?”
reduction of the amount of oxygen in a package by mechanically evacuating the oxygen, displacing the oxygen with another gas or combo of gases, or otherwise controlling oxygen content in a package to a level below that normally found in the surrounding atmosphere
What methods are included in “reduced-oxygen packaging”?
altered atmosphere
modified atmosphere
controlled atmosphere
low oxygen
vacuum packaging
What is normal ambient air comprised of?
Oxygen 20.96%
Nitrogen 78.08%
Carbon dioxide 0.03%
How are oxygen contents changed?
removal of oxygen
other gases are replaced (nitrogen, CO2)
What are the two primary organisms found in reduced-oxygen packaging?
Clostridium botulinum
Listeria monocytogenes
What are the non-microorganism concerns for reduced-oxygen packaging?
spoilage organisms (aerobic) are no longer indicators of temperature abuse
extended shelf life allows slow growers to proliferate under refrigeration temperatures
Define “partially cooked”
potentially hazardous foods that have not been sufficiently cooked to assure commercial sterility or fail to have barriers to prevent the growth of or toxin formation by D. botulinum