Section 2 (Food Safety Hazards)

Question 1

What does microbial contamination consist of?

Answer 1

Bacterial and viral contamination. (Viruses are 100x smaller than bacteria.)

Question 2

What are bacteria?

Answer 2

Microorganisms generally too small to be seen without a microscope, which are the most common form of microbial contamination in the food industry; pathogenic bacteria cause food-borne illness, and spoilage bacteria cause food to perish or rot.

Question 3

What are typical sources of bacteria in the food industry? (1)

Answer 3

Raw food (fruit, vegetables, meat, poultry, fish, shellfish, eggs, untreated milk) carrying bacteria from the environment and/or animal intestines;

Question 4

What are typical sources of bacteria in the food industry? (2)

Answer 4

People (human skin, ears, nose, throat, hair and intestines), which can contaminate food through poor personal hygiene and poor safety practices;

Question 5

What are typical sources of bacteria in the food industry? (3)

Answer 5

Air and dust (containing pathogenic bacteria able to settle on food); equipment (on improperly cleaned surfaces); soil (from raw unwashed fruit and vegetables);

Question 6

What are typical sources of bacteria in the food industry? (4)

Answer 6

Pests (animals, birds and insects) as they are carriers of bacteria in and on their bodies; untreated/inadequately treated water which can contaminate ready-to-eat foods;

Question 7

What are typical sources of bacteria in the food industry? (5)

Answer 7

And finally, food waste (unclearly identified, improperly contained and/or not disposed of regularly), which can be used accidentally and/or attract pests.

Question 8

How do bacteria multiply?

Answer 8

A process called binary fission: 1 becomes 2, 2 become 4, 4 become 8 and so on.

Question 9

When is food poisoning caused?

Answer 9

Only if a person is infected by more than a certain number of bacteria, depending on the type; it ranges from 100 for E. coli to over 1 million for Clostridium perfringens.

Question 10

What are the conditions for bacterial growth?

Answer 10

Food (especially high protein/nitrogenous foods like meat or meat products, poultry, eggs, dairy and seafood); time in optimum conditions; warmth (5 - 63 degrees C, with 37 - body temperature - being the best); moisture; a pH between 6 and 8 (not lower than 4.5 for most) and oxygen (for most).

Question 11

What are bacterial spores?

Answer 11

Hard, shell-like structures formed in unfavourable conditions, containing everything needed to continue life once conditions improve; they revert back to the bacterium and can multiply again, even after years.

Question 12

What are examples of spore-forming bacteria?

Answer 12

Bacillus cereus (rice and rice dishes), Clostridium perfringens (meat and soil on vegetables) and Clostridium botulinum (canned/bottled/vacuum-packed fish, meat, vegetables and sauces).

Question 13

What are toxins?

Answer 13

Poisonous substances that are heat-resistant and will therefore survive the cooking process to cause illness.

Question 14

What are examples of toxin-producing bacteria?

Answer 14

Staphylococcus aureus and Clostridium botulinum.

Question 15

What are high risk foods?

Answer 15

Ready-to-eat, cooked/processed, high-protein, moist foods. (Cold cooked/smoked/cured meat, poultry fish and seafood; ready meals containing gravy or sauces; egg products (quiche); cold cooked rice (rice salad); and dairy-based products (cream desserts).)

Question 16

What is ready-to-eat raw food?

Answer 16

Fruit and vegetables eaten without cooking.

Question 17

What is raw food that is to be cooked?

Answer 17

Meat, poultry, fish, eggs, dairy products and whole vegetables, which are often chilled or frozen to slow bacterial growth.

Question 18

What are low-risk foods?

Answer 18

High-acid products (vinegar/pickled foods); high-sugar products (chocolate, confectionery, and jam); dry products (cereals, bread, biscuits, dry pasta and dried vegetables) and high-salt products (dry cured meat).

Question 19

Which processed kill all bacteria in food?

Answer 19

Sterilisation, ultra heat treatment (UHT) and canning.

Question 20

What are examples of preserved foods that require refrigeration?

Answer 20

Vacuum packaged foods (air around food is removed); modified atmosphere packaging foods (MAP - air surrounding food is replaced to slow bacterial, yeast and mould growth); smoked foods (outside is dried, and smoke directly kills some microorganisms); and pasteurised foods (treatment to kill pathogens and spoilage organisms).