This presentation is done by 2010/2011 batch of Export Agriculture students of Uva Wellassa University of Sri Lanka as a requirement for the subject which is “Post harvest technology”. Note that the information included here is relevant to Sri Lankan condition.

1. Post Harvest Handing Of Citrus
Group no : 02
Export Agriculture

2. Introduction
• By the year 2050, the world population is expected to
reach 9 billion people
• Demand for food will increase by 60 percent
( United Nations Food and Agriculture Organization)
• Increasing food production is not enough
• Roughly one-third of the food produced in the world
goes to waste – a staggering 1.3 billion tons every year
• In the fight against global hunger, we must also address
postharvest los.

3. • Postharvest loss - Collective food loss all along the food
production chain, from harvest and handling, to
storage and processing, to packing and transportation
• The causes of postharvest loss are varied and complex,
depending upon weather, region, and crops
• But common culprits in the developing world include
lack of proper storage, lack of transportation, and lack
of information on where and how food is lost
• To escape from this problem, it is require to do
“Proper Post Harvest Handling”

4. Post Harvest Handling
• In agriculture, postharvest handling is the stage of crop
production immediately following harvest, including
cooling, cleaning, sorting and packing
• The instant a crop is removed from the ground, or
separated from its parent plant, it begins to deteriorate
• Post-harvest treatment largely determines final
quality, whether a crop is sold for fresh consumption,
or used as an ingredient in a processed food product
• Effective handling decreases postharvest losses

5. Citrus
 Non climacteric fruit
 Major Growing Areas : Dry and Intermediate
zones
 Economics & Marketing availability
 Lemon : April - August
 Lime : April - July
 Grapefruit : May -August

6. Scientific Classification
• Kingdom : plantae
• Phylum : magnoliophyta
• Class : magnoliopsida
• Order : sapindales
• Family : rutaceae
• Genus : citrus L.

7. Important Species
 Citrus aurantiifolia – Key Lime
 Citrus maxima – Pomelo
 Citrus medica – Citron
 Citrus reticulata – Mandarin orange

9. Important hybrids
 Citrus × aurantium – Bitter orange
 Citrus × latifolia – Persian lime
 Citrus × limon – Lemon
 Citrus × limonia – Rangpur
 Citrus × paradisi – Grapefruit
 Citrus × sinensis – Sweet orange
 Citrus × tangerina – Tangerine
 Most of these varieties are resistant to post
harvest losses

11. Anatomy of Citrus fruit

12. Postharvest Deterioration
 Harvested fruit continue respiration
 Loose water but not replaced
 The respiratory rate of the rind is nearly ten
times as high as that of vesicles
 Rind plays a important physiological role in
the qualitative changes in storage
 Respiratory rates are stimulated by dropping
and bruising

13. POST HARVEST HANDLING OF CITRUS
• Normally 30-40% of Citrus fruit loss due to lack of
proper post harvest handling practices
• Visible characteristics change in post harvest losses
– Anatomical Characteristics
– Physiological Characteristics
– Morphological Characteristics

14. TYPES OF POST HARVEST LOSSES
1. Physiological disorders
2. Diseases

15. 01. Physiological Disorders
• Influence quality in the markets
• Causes: Pre- and post-harvest factors
• Pre harvest: B, and Cu deficiency,
ammoniation, Zebra skin, fruit-splitting,
creasing, sun burn, wind scar and freezing

16. • Postharvest factors:
– Temperature, humidity, gaseous composition,
mechanical stress and aging
• Disorders: Puffiness, pitting, chilling injury,
granulation, oleocellosis,
stem end down, stylar-end breakdown,
and freezing injury

17. Blossom-End Clearing
 BEC has also been referred as “wet bottoms,”
“stylar-end clearing,” “water bottom,”
“waterlog,” and “wet wick”
 Symptoms:
– translucent, water soaked appearance of the
fruit peel (commonly at the blossom end)
– caused by internal bruising and juice leakage
from juice vesicles

18.  BEC affected fruit develop off flavors
 Visible within 24 hours after bruising
 Can affect up to 90% of the fruit in some
loads
External symptoms of blossom-end clearing on
grapefruit (left) compared to an un-injured fruit (right)

19. Internal symptoms of BEC on grapefruit

20. Factors Involved in BEC Development
 Fruit characteristics;
– Seedless grapefruit (e.g. 'Ruby Red' or 'Marsh')
are most affected
– Small fruit likely to develop BEC than large fruit
– Thicker-skinned fruit develop less BEC than thin-skinned
fruit under the same conditions
– The severity of BEC varies widely from year to
year and from grove to grove
– BEC develops most often in late-season fruit

21. • Rough Handling
– BEC never occurs while fruit are still attached to
the tree
– Never develop on fruit handled very gently
– Rough handling is the primary cause of fruit BEC
– Most BEC develops as a result of rough handling in
the packing house

22. • Temperature & RH
– BEC increases with higher temperatures
– Harvesting earlier in the morning ,when
fruit temperatures are cooler will reduce
the incidence of BEC
– Holding fruit at low humidities prior to
packing increases fruit susceptibility to BEC
compared to holding it at high humidities

23. Recommendations to Reduce BEC
• Carefully handle fruit during all harvesting and
packing operations
• Harvest fruit earlier in the morning when fruit
temperatures are lower
– Be cautious, however, that fruit are not so turgid that
oil spotting (oleocellosis) results
• Allow susceptible fruit harvested under warm
conditions to cool overnight (e.g. to 70oF or
below) before packing
• Always hold fruit under high relative humidities

24. Other Physiological Disorders
I. Granulation
• Fruit which is dry or ricey
• Causes:
– over maturity, sun burn, freezing, lack of
water, excessive tree vigor, mite damage,
cool, dry and windy conditions
• Keeping trees well irrigated will avoid fruit
from drying out

25. 2. Oleocellosis (Oil spotting)
• Navel oranges, lemons, and limes mostly
affected.
• Oil released from broken peel oil cells in the
flavedo.
• Oils are toxic to the surface of the peel and
cause necrosis of the surface cells
• Can reduced by avoiding harvest until the fruit
get turgid

26. Chilling Injury (CI)
• Collapse is not targeted oil glands
• A collapse of discrete areas of the peel from
sunken darkened lesions which will slowly
expand.
• Low RH enhance CI
• Waxing-Reduce but not eliminate CI

27. Stem-End Rind Breakdown
• Thin skinned fruit are more affected than thick
skinned fruit.
• Collapse of rind tissues resulting in sunken
brown area which is irregular in shape.
• Narrow ring of unaffected tissue immediately
around the stem area which has no stomata.
• Control
-Hold fruits at high RH

28. Post Harvest Diseases of Citrus Fruits
 Anthracnose- Colletotrichium gloeosporioides
 Septoria spot- Septoria depressa
 Blue & Green Mould-
 Penicillium digitatum (green mould)
 P. italicum (blue mould)
 Sour Rot- Galactomyctes citri-aurantii

29. Anthracnose
 Symptoms
⁻ Superficial leathery appearance
⁻ Silver/grey to dark lesions
⁻ Tear-staining pattern
⁻ Pink spores under humid conditions
 Occurrence
⁻ Infection occurs by rain-splash during autumn
⁻ Ethylene degreening increases sensitivity to
anthracnose

30. • Management
Dead wood should be pruned as the fungus
harbours in dead branches
Copper-based fungicides application before
monsoonal rains
Postharvest treatment with Benzimidazole
fungicides may reduce fruit losses

31. Septoria spot
• Symptoms
 Dark brown collapsed lesions, with a purple tinges
 Black specks develop in decayed area
• Occurrence
 Mainly inland citrus regions
 Fruit more susceptible after frosts
• Management
 Field application of copper-based fungicides

32. Blue & Green Mould
Symptoms
 Softening of damaged tissue
 White fungal growth, which progressively
turns blue or green as spores develop
 Occurrence
 Infections develop from damaged areas
 The growth of mould increases with
storage temperatures
 Late season fruit more susceptible

33.  Management
 Good hygiene and sorting
 Sanitation destroys spores in recirculating
water and packing line equipment
 Apply postharvest fungicides within 24 hours
 Lower storage

34. Sour Rot
• Symptoms
 Very soft, watery decay
 Distinct margin between decayed & healthy
tissue
• Occurrence
 Infection occurs in damaged fruit
 Sour rot spores in soil can accumulate in
recirculating water in dips and drenches
• Management
 Careful handling reduces rind damage
 Apply Guazatine fungicide within 24hrs of
harvest

35. Some Other Diseases
 Stem end rot
 Black rot
 Brown rot
 Botrytis rot

36. Postharvest Storage
• Citrus fruits have relatively long post harvest
life
• Loose skinned fruits easily deteriorate at high
humidity
• Pre storage curing of the fruits also reduces
decay and chilling injury during storage
• Each variety has different optimum conditions
for storage

37. Controlled-atmosphere storage
 Research has been done
 Commercially not used because:
– Economic reasons
– Physiological characteristics of fruit
– Elevated CO2 has no beneficial effect
– Low O2 stimulates ethanol and
acetaldehyde

38. Group Members
 UWU/EAG/11/0026 S.Rishibamathana
 UWU/EAG/11/0027 T.A.D.D.L.Thanaweera
 UWU/EAG/11/0028 D.N.Nanayakkara
 UWU/EAG/11/0029 Y.S.M.M.P.Yallarawa
 UWU/EAG/11/0030 M.Aphinaya
 UWU/EAG/11/0031 R.A.S.N.Ranasinghe

39. Thank You!