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Unit notes and practice questions

Grade 12 Agriculture unit 16: Safe Food Production and Postharvest Handling

Everything here is for unit 16 of the Grade 12 Agriculture textbook: what the chapter covers, the short notes, practice questions with their answers, and the lesson video where one exists.

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4
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10
Practice questions on unit 16
272–282
The textbook pages for unit 16

What unit 16 covers

  1. 1.Food safety hazards and health risks
  2. 2.Source of food contaminants
  3. 3.Food safety and nutrition linkage
  4. 4.Indigenous knowledge in safe food production

Short notes for unit 16

The cards filed under this chapter on the Grade 12 Agriculture page. Open one at a time.

Biological HazardCommonly Found In
SalmonellaEggs, poultry, meat, unpasteurized milk or juice, cheese, fruits, spices, nuts
NorovirusProduce, shellfish, ready-to-eat foods
CampylobacterRaw and undercooked poultry, unpasteurized milk, contaminated water
E. coliUndercooked ground beef, unpasteurized milk, raw milk cheeses, contaminated water
ListeriaReady-to-eat deli meats and hot dogs, unpasteurized milk, raw milk cheeses
Clostridium perfringensBeef, poultry, gravies

When you use it

Use when identifying specific microbial pathogens and the primary food products they contaminate.

Watch out

Listeria and Norovirus are commonly found on ready-to-eat foods, whereas Campylobacter and Salmonella are primarily linked to raw poultry and unpasteurized products.

Drafted from Grade 12 Agriculture, pages 268-280, then checked twice before it went up

Chemical HazardDescription and Source
MycotoxinsToxins produced by moulds and fungi growing on crops
Natural ToxinsBiochemical compounds produced by plants in response to stressors
Marine ToxinsDecomposition or microscopic marine algae in fish and shellfish
Processing-induced ChemicalsChemicals formed by reactions between natural components during processing
PesticidesAgrochemicals used to control, destroy, or repel agricultural pests

When you use it

Use when classifying chemical hazards that enter foods naturally, from pests, or during processing.

Watch out

Mycotoxins are produced by fungal moulds on crops, whereas natural toxins are defensive biochemicals produced directly by the plants.

Drafted from Grade 12 Agriculture, pages 268-280, then checked twice before it went up

Physical Hazard TypeExamplesHealth Risk
NaturalStems in fruit, bones in fish, dirt on potatoes, insect fragmentsPuncture or choking risk, can be harmless
UnnaturalMetal fragments, pieces of plastic, wood chips, glassGenerally more dangerous to health

When you use it

Use when categorizing foreign objects found in food as natural parts of raw food or unnatural contaminants.

Watch out

Unnatural hazards such as glass, metal, and plastic are generally more hazardous than natural objects like bones or stems.

Drafted from Grade 12 Agriculture, pages 268-280, then checked twice before it went up

When you use it

Use when explaining how microbial, chemical, and physical contaminants enter food raw materials and processed products.

Watch out

Contamination sources include not only environmental vectors like water, air, and soil, but also the internal organs of animals and accidental chemical mixing.

Drafted from Grade 12 Agriculture, pages 268-280, then checked twice before it went up

Practice questions on unit 16

10 multiple-choice questions written against this chapter, each with its answer and the reason. Try one before you open the answer.

Question 1

According to the textbook, what are the four primary categories of food safety hazards?

  1. A.Bacterial, viral, fungal, and parasitic
  2. B.Biological, chemical, physical, and allergenic
  3. C.Soil, water, air, and animal
  4. D.Natural, processing, packaging, and storage
Show the answer and why

Answer: B Biological, chemical, physical, and allergenic

Why

The text states that there are four primary categories of food safety hazards to consider: biological, chemical, physical, and allergenic.

Question 2

What characterizes biological food safety hazards?

  1. A.Unintentional mixing of agricultural pesticides
  2. B.Foreign solid objects such as wood chips and glass
  3. C.Contamination of food by microorganisms
  4. D.Toxic chemicals formed during industrial cooking
Show the answer and why

Answer: C Contamination of food by microorganisms

Why

Biological hazards are characterized by the contamination of food by microorganisms, such as bacteria and viruses.

Question 3

Which of the following is classified as an unnatural physical hazard in food?

  1. A.Pieces of plastic
  2. B.Stems in blueberries
  3. C.Bones in fish
  4. D.Dirt on potatoes
Show the answer and why

Answer: A Pieces of plastic

Why

Pieces of plastic, metal fragments, wood chips, and glass are examples of unnatural physical hazards, whereas stems, bones, and dirt are natural physical hazards.

Question 4

Which group lists major sources of food contamination identified in the textbook?

  1. A.Sunlight, crop genetics, and elevation
  2. B.Soil minerals, crop variety, and wind speed
  3. C.Cooking heat, packaging color, and store location
  4. D.Water, air, equipment, insects, and employees
Show the answer and why

Answer: D Water, air, equipment, insects, and employees

Why

Section 16.2 lists water, air, dust, equipment, sewage, insects, rodents, and employees as major sources of food contamination.

Question 5

What type of chemical hazard is produced by fungi or moulds that grow on crops and foods under certain conditions?

  1. A.Marine toxins
  2. B.Mycotoxins
  3. C.Processing-induced chemicals
  4. D.Natural plant stressors
Show the answer and why

Answer: B Mycotoxins

Why

Mycotoxins are chemical hazards produced by fungi (moulds) that grow on crops and foods, and they can be toxic to humans and animals.

Question 6

According to the textbook, which biological pathogen is commonly found in raw and undercooked poultry, unpasteurized milk, and contaminated water?

  1. A.Norovirus
  2. B.Listeria
  3. C.Campylobacter
  4. D.Clostridium perfringens
Show the answer and why

Answer: C Campylobacter

Why

Table 16.1 lists Campylobacter as being commonly found in raw and undercooked poultry, unpasteurized milk, and contaminated water.

Question 7

How do marine toxins accumulate in seafood such as fish and shellfish?

  1. A.Through reactions between natural components during high-heat processing
  2. B.By accidental spraying of agricultural pesticides onto water bodies
  3. C.By intentionally adding chemical preservatives such as sodium nitrate
  4. D.Through decomposition or microscopic marine algae accumulated in fish and shellfish
Show the answer and why

Answer: D Through decomposition or microscopic marine algae accumulated in fish and shellfish

Why

Table 16.2 defines marine toxins as originating from decomposition or microscopic marine algae accumulated in fish and shellfish.

Question 8

How do unnatural physical hazards compare to natural physical hazards regarding human health?

  1. A.Unnatural physical hazards are generally more dangerous to health.
  2. B.Natural physical hazards are always far more dangerous than unnatural ones.
  3. C.Both natural and unnatural hazards carry no risk of puncture or choking.
  4. D.Unnatural physical hazards are completely harmless to human health.
Show the answer and why

Answer: A Unnatural physical hazards are generally more dangerous to health.

Why

The textbook states that unnatural physical hazards are generally more dangerous to health, whereas natural physical hazards can be harmless.

Question 9

Based on the textbook table of biological hazards, which pathogen is commonly found in beef, poultry, and gravies?

  1. A.Norovirus
  2. B.Clostridium perfringens
  3. C.Listeria
  4. D.E. coli
Show the answer and why

Answer: B Clostridium perfringens

Why

Table 16.1 specifically states that Clostridium perfringens is commonly found in beef, poultry, and gravies.

Question 10

What are processing-induced chemical hazards as defined in the textbook?

  1. A.Toxic compounds produced by moulds on stored grains
  2. B.Pesticides applied to control or destroy field pests
  3. C.Undesirable chemicals formed during processing from reactions between natural food components
  4. D.Biochemical compounds produced by plants in response to stressors
Show the answer and why

Answer: C Undesirable chemicals formed during processing from reactions between natural food components

Why

Table 16.2 explains that processing-induced chemicals are formed in certain foods during processing as a result of reactions between natural components of the food.

The app holds 12 questions on this unit, marked as you go. These are the first 10.

The textbook pages for unit 16

Unit 16 runs from page 272 to page 282 of the Ministry of Education edition.

Ministry of Education edition, English, 302 pages

Download the PDF

All Grade 12 Agriculture short notes

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