Gilmour - Food & Industrial Microbiology

Question 1

why are most bacteria inedible?

Answer 1

high conc of nucleic acids which contain purines which is converted to uric acid which leads to gout

Question 2

name 4 common microbes humans consume

Answer 2

fungi (mushrooms)
edible algae
spirulina
yeasts

Question 3

name 2 types of anaerobic fermentation

Answer 3

homolactic and heterolactic

Question 4

what is homolactic fermentation?

Answer 4

pyruvic acid to lactic acid

Question 5

what is heterolactic fermentation?

Answer 5

pyruvic acid to lactic acid, CO2 and ethanol

Question 6

what is ethanolic fermentation?

Answer 6

pyruvate to ethanol and CO2

Question 7

which compound gives undesirable flavours in fermentation?

Answer 7

acetylaldehydes

Question 8

what are the benefits of eating fermented foods?

Answer 8

preserves foods, improves digestibility and adds flavour

Question 9

what makes milk go sour?

Answer 9

oxidised f/a’s

Question 10

why does putrefied meat smell?

Answer 10

a/a breakdown produces amines eg cadavarin

Question 11

name a pathogenic bacteria found in contaminated foods and its effect on people

Answer 11

Campylobacter from chickens - diarrhea (fatal in immunocompromised patients)

Question 12

name 10 methods of food preservation

Answer 12

salting/drying/cooking/fermenting/freeze drying/refrigeration/vacuum packing/pasteurisation/canning/ionising radiation

Question 13

define bioprospecting

Answer 13

the search for plant and animal species from which medicinal drugs and other commercially valuable compounds can be obtained

Question 14

name 5 industrial strain microbe attributes

Answer 14

genetic stability and easy manipulation
inexpensive growth requirements
safe
high level product expressions
ready harvesting of the product

Question 15

what are upstream and downstream processing?

Answer 15

upstream: culture of MOs in large quantities
downstream: harvesting cells and product recovery