PPT720S - POSTHARVEST PHYSIOLOGY AND TECHNOLOGY - 2ND OPP - JAN 2023


PPT720S - POSTHARVEST PHYSIOLOGY AND TECHNOLOGY - 2ND OPP - JAN 2023



1 Page 1

▲back to top


nAmI BIA unIVERSITY
OF SCIEnCE Ano TECHnOLOGY
FACULTYOF HEALTH, NATURAL RESOURCESAND APPLIEDSCIENCES
DEPARTMENT OF AGRICULTURE AND NATURAL RESOURCESSCIENCES
QUALIFICATION: BACHELOR OF HORTICULTURE
QUALIFICATION CODE: 07BHOR
LEVEL: 7
COURSE CODE: PPT720S
DATE: JANUARY 2023
COURSE NAME: POSTHARVESTPHYSIOLOGYAND
TECHNOLOGY
DURATION: 3 HOURS
MARKS: 100
SECONDOPPORTUNITYEXAMINATION QUESTION PAPER
EXAMINER(S) Dr Norman Muzhinji
MODERATOR: Dr Brian Makeredza
INSTRUCTIONS
1. Answer ALL the questions.
2. Write clearly and neatly.
3. Number the answers clearly.
PERMISSIBLEMATERIALS
1. Examination question paper
2. Answering book
THIS QUESTION PAPER CONSISTS OF 3 PAGES (Excluding this front page)

2 Page 2

▲back to top


Section A: Multiple choice questions (15 marks)
1. . Which is the precursor of Ethylene
A. Tryptophane
B. Methionine
C. ABA
D. IAA
2. Storage of fruits and vegetables, where the gas composition is changed from that of normal
atmosphere and a precise control is maintained over the atmospheric composition during
storage period is known as;
A. Cold storage
B. Hypobaric storage
C. Modified Atmospheric storage
D. Controlled atmospheric storage
3. Individual shrink wrapping for packaging is generally most suitable for
A. Climacteric commodities
B. Semi-climacteric commodities
C. Non-climacteric commodities
D. Both a) and b)
4. The most reliable maturity index for several fruit is
A. Dry matter
B. Soluble solid concentration
C. Skin color
D. Specific gravity
5. For better post-harvest quality, the cut flowers should be harvested during
A. Evening hours
B. Early morning hours
C. Noon time
D. Mid-day
6. Waxing of fruits is done mainly to reduce
A. Transpiration
B. Respiration
C. Ripening
D. Transpiration and respiration
7. The browning of fresh potato cut surface is due to
A. Non-enzymatic browning
B. Mallard reaction
C. Fermentation
1

3 Page 3

▲back to top


D. Enzymatic browning
8. Symptoms associated with chilling injury are
A. Surface pitting
B. Internal discoloration
C. Water-soaked tissues
D. Failure to ripen
E. All of the above
9. The major indicator and a useful guide to predict the potential storage life of the fruits and
vegetables is
A. Water uptake rate
B. Rate of ascorbic acid loss
C. Rate of mineral uptake
D. Respiration rate
10. Crops which have higher moisture content generally have
A. Poorer storage characteristics.
B. Taste nice
C. Low rates of respiration
D. Are good for the market
11. In most fruits and vegetables, changes in colour is due to degradation of chlorophyl. Which of
the following factors is not responsible for degradation of chlorophyll?
A. pH
B. Oxidation
C. Enzymes
D. Malic acid
12. Which pigments are responsible for the red colour in tomatoes?
A. Chlorophyl
B. Lycopene
C. Carotenoids
D. Tannins
13. When can a fruit or vegetables be harvested
A. At physiological maturity
B. Ripening
C. Senescence
D. After 3 months
14. Fruit stem end rot is one of the most devastating diseases affecting fruits post-harvest.
is the causative agent of fruit stem end rot?
A. Too much auxins in the plant
B. Fungal infection
What
2

4 Page 4

▲back to top


C. Harvesting too early
D. Enzymatic browning
15. Example of Climacteric fruit
A. Banana
B. Citrus
C. Litchi
D. Grape
Section B: Answer all questions(85 MARKS)
1. Write short notes on the following terms, giving examples
a. Climacteric and non-climacteric fruits
(4)
b. Qualitative post-harvest losses and quantitative post-harvest losses
(4)
2. Describe the postharvest factors affecting the quality of post-harvest life of fruits and
vegetables
(16)
3. Most fruits and vegetables at harvest are made up of water.
a. Why do fruits and vegetables lose water and what effects does this have on the quality of
the produce?
(6)
b. Identify the factors responsible for water loss in fruit and vegetables and outline strategies
that you wou!d implement to mitigate the water loss problem.
(10)
4. a. Define the term pre-cooling of vegetables?
(2)
b. Describe the various methods of pre-cooling of fruits and vegetables.
(8)
5. Mention two main physiological activities that take place in growing plants and harvested
produce which have implication on how long they can be kept?
(2)
6.Explain briefly six (6) strategies that you can use to reduce post-harvest losses in fruits and
vegei3bles produce
(12)
7. A Food Safety Manager at Namibia Fresh Produce Market is reviewing the shipment that came
in late yesterday. She noticed that the strawberries have decayed. What should she do? (1)
8. Assume you have been appointed as a manager to oversee the operations of Mashare Irrigation
Scheme responsible for production of spinach. Make your best recommendation for harvesting
and handling harvested spinach assuming the irrigation scheme lack refrigerated storage
facilities?
(4)
9. a. List four (4) parameters that are used to determine the quality of fruits and vegetables. (4)
b. Describe the factors that determine the quality fruits, vegetables, and flowers?
(6)
10. a. Describe at least four (4) sources of microorganisms responsible for fruits and vegetables
spoilage.
(4)
b.List at least two (2) the methods that can be used to reduce microbial spoilage in fruit and
3