microbes and food spoilage

Question 1

yeast - growing conditions

Answer 1

food - carbohydrate based foods
oxygen - facultative microbes
temperature - 25C-39C
pH - pH 4-5

Question 2

main cause of food spoilage - enzymes - ripening

Answer 2

-fruit and veg contain the enzymes necessary for ripening
-under ripe (often inedible) to ripe (edible) to over ripe (beginning of physical decay)
-

Question 3

main cause of food spoilage - enzymes - browning

Answer 3

-some fruit and veg become brown in colour when exposed to air during food preparation such as chopping or slicing
-due to air reaction g with enzymes such as oxidation

Question 4

main cause of food spoilage - moisture loss

Answer 4

-affects fruit and veg after they have been harvest
-no longer absorb moisture from the soil through their roots, so they become dehydrated, which results in shrinkage

Question 5

main cause of food spoilage - microbe contamination

Answer 5

-yeats contaminate the exterior of food such as fruits
-moulds contaminate the exterior of food such as oranges and bread

Question 6

salmonella - description

Answer 6

rod shaped
bacilli
no spores
gram negative

Question 7

salmonella - environment

Answer 7

facultative
37*C

Question 8

salmonella - sources

Answer 8

intestine of human and animals
rodents and pests
unwashed hands

Question 9

salmonella - duration

Answer 9

1-7 days

Question 10

salmonella - symptoms

Answer 10

abdominal pain
fever
diarrhoea
vomitting