Water activity (Aw) and microorganisms (with microbial growth)

Question 1

Define Water activity

Answer 1

ratio of vapor pressure of water in solutions (Ps) to the vapor pressure of pure water (Pw)

Question 2

Aw=Ps/Pw means what

Answer 2

water activity does not equal % moisture

Question 3

how to manipulate Aw

Answer 3

remove moisture
add solute (as you increase solute you decrease freezing point)

Question 4

what are some microorganisms

Answer 4

bacteria
protozoa
viruses
fungi

Question 5

Good microorganisms

Answer 5

probiotic organisms, fermentation

Question 6

bad microorganism

Answer 6

spoilage organisms

Question 7

ugly microorganisms

Answer 7

pathogens, toxin producers: e coli and samonella

Question 8

Fungi division

Answer 8

1. binary fission
2. germ tube
3. budding

Question 9

Bacteria division

Answer 9

binary fission