Flashcards in Extrinsic Factors chpter 4 Deck (20):
What is the difference between extrinsic and intrinsic factors?
Extrinsic factors are factors that can be controlled without changing the food. While intrinsic factors often change the food.
What are the two main extrinsic factors?
Temperature and gaseous environment
What is the danger zone?
4.4-60C Most microorganisms grow in this range.
Minimum growth Temp?
Lowest temp that an organism will grow. SLow growth to no growth. Just cell maintenance.
Optimum growth temp?
Temp at which growing fastest.
Maximum growth temp?
Temp in whcih cells cannot make any more enzymes, start to die.
Kill all viable cells at what temp?
Kill all cells at what temp?
Using pressure as well. 100C kills all growth.
at 121C SPORES KILLED.
What microorganisms can be survive below 4C?
Listeria, C. botolinum, and yersina entercolitica
Parasites (destroy by below -20C). Viruses are fine.
What is used to store bacteria?
Glycerol, it prevents crystalization so we cna store bacteria.
<20C cold lovers. Vibrio
30C found in fridge.
>35C potimal. 7-10C min and 40-60C max
Endospore forming survives but do not grow at temp> 60C
optimal > 45C SPORES or up till 80C
What is the difference between endospores and fungi spores
Endospores from bacteria are heat resistant to heat, drying, and disinfecting chemicals.
While fungi spores are NOT heat resistant.
Describe what bacteria is found in aerobic conditions
Gram -, non-spore forming, rods (speudomonaus), oxidateive and breakdown of fats and proteins. odor found at 10^6- 10^7 CFU/g of meat. Gives off CO2.
gram +, spore forming, LAB, fermetnave and converts sugar to LA and acetic acid. spoilage is detectable after max population reached.
Low redox potentials. Souring occurs.
What is a facultative anarobe
It can survive in both oxygen and no oxygen conditions.