Chapter 9: Microbial Control

Question 1

-cide vs. -static

Answer 1

-cide
○ Killing ability
○ Bactericide, viricides,
fungicides, etc.

-static
○ Growth limiting ability
○ Bacteriostatic and
fungistatic drugs

Question 2

Antimicrobials should be

Answer 2

Inexpensive
Fast-acting
Stable during storage
Harmless to humans but effective at controlling microbial growth
Selective

Question 3

Differentiate between thermal death time and decimal reduction

Answer 3

Thermal death time is the time to sterilize a volume of liquid at a set temp
Decimal reduction is the time required to destroy 90% of microbes in a sample

Question 4

Define the parameters for autoclaving and pasteurization

Answer 4

Autoclaving
121 C, 15 psi, 15 min.
Sterilizes

Pasteurization
Low-Temperature, Long-Time 63 °C for 30 minutes
High-Temperature, Short-Time 72 °C for 15 seconds
Ultra-High Temperature (UHT) (for shelf-stable milk/juice)
138–150 °C for 1-2 seconds
disinfect, not sterile