intro

Question 1

Contron measure stages in food chain to avoid food poisoning

Answer 1

1) Raw material (Bird/ animal / plant) –> Salughter/ harvest
2) –> not processed OR processed
3) –> Retail
4) –> consumer

Question 2

Control measure at food chain stage of raw material

Answer 2

Good husbandry practices

Question 3

Control measure at food chain stage of Salughter/ harvest

Answer 3

hygiene decontamination

Question 4

Control measure at food chain stage of processing

Answer 4

Heat treatment/ Drying/ Preservatives/ Gas atmosphere

Question 5

Control measure at food chain stage of retail

Answer 5

Refridgration

Question 6

Control measure at food chain stage of customer

Answer 6

Hygiene/ cook properly/ Avoid cross- contamination

Question 7

Bacteria causing foodborne illness from animal

origin

Answer 7

• campylobacter jejuni/ coli
• Salmonella enterica
• Escherichia coli O157

Question 8

Bacteria causing foodborne illness from human origin

Answer 8

• Staphylococcus aureus

- Norovirvus

Question 9

Straphylococcus aureus

Characteristics / mechanism / Syptoms / incubation time

Answer 9

Gram- positive
Producing toxin
Cause vomiting, abdominal cramps
Incubation 6- 8hr

Question 10

Norovirus

syptoms/ spreading pathway

Answer 10

causing nausea, vomiting,

ususally spread by person- to - person contact

Question 11

Bacteria causing foodborne illness from environmental sources

Answer 11

Listeria monocytogens

Question 12

Listeria monocytogenes

symptoms/ incubation time/ found in

Answer 12

causing mild flu, meningitis, abortion
incubation 1-90 days
Found in silage, decaying vegetation, may colonise drains and food processing machinery.
Sheep with listeriosis may contaminate vegetation

Question 13

Bacteria causing foodborne illness from seafood origin

Answer 13

• Vibrio parahaemolyticus

- Vibrio vulnificus

Question 14

Anaerobic spore formers

Answer 14

• Clostridium botulinum

- Clostridium perfringens

Question 15

Clostridium botulinum

Characterisitic/ mechanism/ symptoms/ incubation time

Answer 15

Proteolytic types: mesophilic
Non- proteolytic: psychrophilic

Very powerful toxin was produced
Causes double vision, weakness, dry mouth, respiratory paralysis.
Incubation period 18- 36hr

Question 16

Clostridium perfringens

characteristics/ mechanisms/ symptoms

Answer 16

Spores on meat survive cooking
may germinate and multiply if food keep warm for long period

causing diarrhoea and abdominal pain

Question 17

Aerobic spore former

Answer 17

Bacillus cereus

Question 18

Bacillus cereus

Food associate with Food poisoning
Characteristics/ mechanism [2] & incubation time

Answer 18

Rice and other cooked food
Spore survive cooking and may germinate and multiply if rice is kept warm for long period

Toxins:
emetic toxin - cause vomiting nausea, [incubate 1-5 hr]
diarrhoeal toxin - diarrhoea, [incubate 12- 24hr]

Question 19

Fungi causing food-borne illness

Answer 19

• Aspergillus flavus

- Penicillium expansum

Question 20

Aspergillus flavus

Mechanism/ Food associated/ Toxin dose/ characteristic
Safe limit

Answer 20

produced aflatoxin, ochratoxin
associated with wheat, rice, maize, peanuts, pistachios etc
- LD(50) : 0.5 - 9 mg/kg
- very carcinogenic for rats
- UK limits: 2ug/kg ; USA limit: 20 ug/kg

Question 21

penicillium expansum

Mechanism/ Food associated/

Answer 21

• produced patulin

- Apple

Question 22

Aspergillus flavus case study

Answer 22

2011
Morrison withdraw all date codes of own brand seasonal Unsalted Pistachio Nuts in shell due to the presence of aflatoxins

Question 23

Protozoan

Answer 23

Cryptosporidium parvum

Question 24

Cryptosporidium parvum

symptoms / mechanism / related source

Answer 24

causes diarrhoea and bloating in humans

water contaminated by livestock mammal feces
Cryptosporidium cysts resistant to chlorination

Question 25

Bacterial food-borne infections

Answer 25

organism is ingested with food • multiplies in the intestine • often attach to the lining of the large or small intestine • some may invade cells of the mucosa • often produce toxins • infectious dose varies but may be quite small

Question 26

Bacterial food-borne intoxications

Answer 26

Organism grows in food • produces toxins in food • toxins are ingested when food is eaten • high numbers of bacteria in food needed to produce illness • symptoms appear relatively soon aftereating food (6-12 h)

Question 27

Non-bacterial food poisoning

Answer 27

* Shellfish poisoning: * Red kidney beans * Scombroid toxin:

Question 28

Shellfish poisoning | Source and symptoms

Answer 28

tingling, numbness, loss of muscular coordination | dinoflagellate algae accumulate in filter feeders

Question 29

Scombroid toxin | Source and symptoms

Answer 29

allergic-like reaction (histamine) | rash nausea, vomiting, diarrhoea (tuna etc.)

Question 30

Red kidney beans | Source and symptoms

Answer 30

vomiting (lectins)

Question 31

microbes that have growth in food

Answer 31

* Salmonella * Escherichia coli O157 * Listeria monocytogenes * Staphylococcus aureus * Clostridium perfringens * Clostridium botulinum * Bacillus cereus

Question 32

microbes that have no growth in food

Answer 32

* Campylobacter jejuni * viruses * Protozoa * Shellfish poisoning * nvCJD (Creutzfeldt– Jakob)

Question 33

Human Defense barriers to infection

Answer 33

``` • Nitric oxide in saliva • Stomach acid ~ pH 2.0 • Degradative enzymes: – lysozyme – pepsin • Flow of food through intestine • Mucous barrier impairs bacterial motility • Competition with resident gut flora • Iron limitation ```

Question 34

Food poisoning

Answer 34

any disease of an infectious or toxic nature caused or thought to be caused by the consumption of food or water

Question 35

A case

Answer 35

illness affecting an individual person

Question 36

An outbreak

Answer 36

an incident involving two or more people thought to have a common exposure or, occurrence of cases of disease in excess of what would normally be expected in a defined community, geographical area or season (WHO).

Question 37

A general outbreak

Answer 37

an outbreak affecting members of more than one private residence or residents of an institution

Question 38

Prevention of food poisoning in the home

Answer 38

- Prevent spread of contamination in the kitchen - Prevent bacteria from growing - Cook to destroy most bacteria