PESEARVATION OF PAPAYA

1. Topic – Post harvest management of papaya
Ranjeet maurya

3. Botanical Name – Carica papaya
Family - Caricaceae
Chromosome no - 2n = 18
Origin place - South mexico

4. Introduction
Papaya (Carica papaya L.) is one of the popular tropical fruits
consumed in the Lao People’s Democratic Republic (PDR).
It is consumed both at the green and ripe stages of development.
Ripe papaya is eaten in the fresh form at breakfast and as a dessert,
it is also used as an ingredient in salads or processed into juices,
jellies, marmalades, candy and crystallised fruit.
Immature green papaya fruits are pickled, used in salads or cooked
and consumed as a vegetable.
Aside from their economic value, consumers are increasingly
becoming aware of the superior nutritional value of papaya and its
bioactive components, which are believed to protect the human body
from disease.

6. Maturity indices
A fruit is considered mature when it has reached the stage of
development, after harvesting and post-harvest handling, at which both
the external and internal quality attributes are acceptable to consumers.
Papayas that are harvested at the correct stage of maturity develop good
peel and pulp colour and have full flavour and aroma at the ripe stage.
Papayas harvested at the immature stage, can be induced to ripen but
the quality of the ripe fruit, and particularly the flavour, is inferior when
compared to naturally ripened fruit. Skin colour is used commercially to
describe papaya maturity. Papayas are harvested when there is a
prominent change in the colour of the skin (about 25 % yellow) .
The dramatic increase in the sugar content of papaya occurs when the
seeds and the pulp change colour, therefore it is recommended that the
fruit is harvested at this stage.
Harvest management practices

7. Time of harvest
Papayas are preferably harvested during midmorning to late afternoon to
minimise latex stains on the fruit, which are unsightly and detract from
consumer appeal. Every effort must be made to avoid harvesting papaya
after it rains since the fruit will be more prone to decay
Method of harvest
When trees are within easy reach, papayas are harvested by hand using
a clean, sharp knife to detach the papaya from the trunk of the tree. For
tall trees, appropriate harvesting tools can be used such as a picking pole
with cloth or net attached at the end, to catch the harvested fruit . If the
tree is too tall to be reached with a picking pole, a ladder should be used
when harvesting the fruit.

8. Harvest management practices

9. Post-harvest handling operations
Post-harvest operations are those undertaken to prepare the produce to
meet the requirements of the target market. These operations can be
carried out in the field, at collection centres or in the packinghouse . The
packinghouse must provide adequate protection from sun and rain, and
must be kept clean at all times. Animals should not be allowed into the
packing area and all workers should practice good hygiene.
Trimming
Trimming refers to cutting the stem that is left on the fruit. If the papaya
is packed with the long stem attached it may injure the peel of other fruit
in the container. Scratching, which may not be seen at the unripe stage,
may appear as discolouration on the skin of the ripe fruit.

10. Cleaning/washing
Infestations by insects such as scale insects and mealy bugs, sooty
moulds and even latex stains are sometimes visible on the fruit and reduce
consumer appeal (. Washing the fruit in water or in 1 percent alum solution
cleans the surface of the fruit and removes any latex adhering to the peel.
Cotton gloves should be used to protect the fruit from cross contamination;
they also protect the hands when removing dirt and other foreign matter
stuck to the fruit. The gloves and the water used for washing should be
clean. The gloves should be washed after they have been used. Before
packing, the fruit should be air-dried on slatted bamboo trays or in front of
blowers.
Sorting/grading
Sorting involves the grouping of papayas based on specific criteria. After
harvest, papayas are classified as either ‘green’ or ‘ripe’. Green papayas
are harvested in the immature state, and may have defects such as insect,
disease (sooty mould) and mechanical damage

12. Poor quality papaya fruit are culled during
sorting

13. Good quality papaya fruit

14. Papayas intended for ripening have no or minimal defects.
Safe, good papaya fruit is mature, clean, wellformed, free from insect and
disease damage, free from mechanical damage such as cuts, abrasions
and punctures, and free from microbial, chemical and physical
contamination. Defects, if any, are only minimal as in the case of windscar
and latex stains.
Post-harvest handling operations

15. Consumers are more likely to reject papayas if they
show the following defects
• insect damage caused by scale insects, mealy bugs, white flies;
• pre-harvest damage such as sooty mould and sunburn;
• damage from harvesting and handling such as latex stains, abrasion,
cuts and punctures;
• premature ripening.
Classifiers or sorters must practice good personal hygiene such as
washing their hands with soap or detergent before handling the
produce. There should also be provision for workers’ comfort during
sorting or grading since uncomfortable positions may lead to fatigue
may lead to fatigue and thus to inappropriate sorting procedures.

16. Papaya harvesting

17. Anthracnose
It is a major cause of post harvest losses in papaya fruit .latent
infections of unripe papayas develop as the fruit ripen. Initially the
lesions appear as small , brown, superficial, water soaked lesions
that may enlarge to 2.5cm or more in diameter
Stem and Rot :-
First symptom appears on fruit pedicle as small lesion which may
spread to fruits surface near the stem area and becomes dark-brown
to black .
Fruit rot:-
Symptoms develops in the stem end or fruit skin wound and can
develop rapidly in ripe fruits as a result of which invaded tissue
shoftens and darkens slightly.

18. Phytophthora stem and rot :-
It begins as water-soaked areas followed by white mycelium growth that
becomes encrusted with time
Post-harvest disease control :-
Hot water treatment (HWT) is by far the most effective post-harvest
treatment against post-harvest diseases . The treatment consists in
dipping mature papayas for 5 to 10 minutes in water heated to 49 to 51
°C. At this temperature range, the decay-causing organisms are killed
without injuring the fruit.

19. Anthracnose Stem and Rot
Fruit rot
Phytophthora

20. Procedure for the hot water treatment
• Fill the tank with enough clean water to completely immerse the fruit-filled
crate in heated water (about 3/4 of the total depth of the tank).
• Heat the water to 51 °C. The temperature should be checked at different
points in the tank.
• Transfer the papayas to be treated into plastic crates. The crate protects the
fruit from being injured by the heat because it prevents contact with the hot
sides and bottom of the tank. Since papayas float in water, place a cover, such
as a net on top of the crates.
• Dip the crates in hot water for 10 minutes .
• If there is no pump to circulate the water, stir the water occasionally to
ensure a uniform temperature in the tank.

21. • The treatment can be shortened to 5 minutes if the papayas are produced
during the dry hot period when conditions are unfavourable to infection in
the field.
• Do not allow the temperature to rise above 51 °C or the fruit will scald or
be injured (Photo 20).
• Remove the crates containing the papayas from the tank.
• Cool the treated papayas for 10 minutes by immersing them in cool water
(hydrocooling), if the fruit is to be taken to a distant market. If quicker
ripening is desired, fast cooling is not necessary. • Allow the fruit to cool and
dry before packing. Faster drying can be achieved by placing the crates in
front of blowers

22. How to regulate ripening
Papayas sold as ripe fruit are ripened before they are distributed to the
wholesale and retail markets. Ethylene, the hormone responsible for
ripening, is produced naturally by fruits and some vegetable crops.
Ethylene from external sources can be used to increase the rate at
which papayas ripen. In Lao PDR, farmers speed the ripening process
by enclosing the unripe papayas in a basket with ‘saman-saman’ or rain
tree (Samanea saman) leaves for 4 to 5 days . The rain tree leaves
produce ethylene and, together with the heat evolved by the fruit,
ripening is induced.
For more rapid ripening (2 to 3 days), some farmers use calcium
carbide, referred to as ‘coal’ in Lao PDR. Chunks of calcium carbide are
wrapped in paper and placed at the bottom of the container, which has
been lined with a plastic sack or paper. Calcium carbide releases
acetylene and heat, which are responsible for the rapid ripening of the
papayas.

23. How to regulate ripening

24. Packaging
Good bulk packaging is essential to maintaining the quality of papayas during
transportation and subsequent handling. The basic functions of bulk packaging
are to contain sufficient quantities of papayas, to protect the papayas during
transportation and handling.
stackable
Rigid containers, such as plastic crates, are highly recommended for the bulk
packaging of fresh papayas since they provide adequate protection against
compression damage (Photo 22a). Their smooth interior allows them to be
easily cleaned. Plastic crates are also stackable, reusable and returnable.
Although more expensive than traditional packaging containers, plastic crates
can be used over extended periods from 5 to 6 years. If plastic crates are used,
the packaging cost per kilogram of produce, is relatively cheaper.

25. Round plastic baskets are smooth inside but are not rigid enough to
protect their contents and they cannot be stacked on top of each other.
When round plastic containers are used for bulk packaging, the vehicle
must be equipped with horizontal dividers so that the contents are not
damaged.
Depending on the intended market, the papayas may be individually
wrapped in a fruit cup made of polystyrene . The polystyrene cup
provides additional protection to the fruit not only during transport but
also during retail handling.
Wooden crates are also rigid bulk packaging containers and provide
adequate protection during transport . When wooden crates are used for
bulk packaging the papayas are individually wrapped. No more than 25
kg of fruit should be put into a wooden crate. Over-packed papayas may
show compression damage on arrival at the market

26. Packaging

27. Packaging of papaya

28. Considerations when using plastic crates
✓Hygiene – plastic crates must be thoroughly cleaned with soap or
detergent after use.
✓Handling – crates must be handled with care during loading, stacking and
unloading. They must not be dropped or used as seats when sorting.
✓ Storage – crates must be stored in a clean area that will prevent
infestation by insects and rodents. They must be stored separately from
chemicals and from farm machinery to prevent contamination. Crates should
not be left exposed to the external environment since they will quickly wear out.
✓Crates used to transport produce must not be used as storage containers for
chemicals (fertilizers and pesticides).

29. https://www.asiafarming.com/wp-content/uploads/2023/05/Papaya-Orchard-
Management1-1024x683.jpg
https://i.ytimg.com/vi/dVqC4M_6EDg/maxresdefault.jpg
https://www.fao.org/3/cb0584en/cb0584en.pdf
Reference
By google crome
https://www.researchgate.net/publication/352991700_Postharvest_losses_of_
papaya_and_practice_for_its_management
Postharvest Technology of Horticultural Crop ( Satish sharma , M.C. Nautiyal )
Principle of Horticulture ( C.R, Adams ,M.P. Early )
Postharvest Horticulture ( Kalyan Barman )