Postharvest and Photosynthesis topic in Postharvest and Biochemistry of Fruits and vegetables

1. POSTHARVEST AND
PHOTOSYNTHESIS
FATIMA SULTAN GUMAMA-ANGELES
Reporter
CS702 POSTHARVEST PHYSIOLOGY AND
BIOCHEMISTRY OF FRUITS AND VEGETABLES

2. TOPIC OUTLINE
OPostharvest Introduction
OPostharvest
OPostharvest Technology
OPost-harvest technology / post-harvest
management
OFunction chain of Post harvest
technology

3. ORole of Post harvest Technologist
OPost harvest Shelf Life
OPostharvest Physiology
OPreservation and Processing
ODifference Between Postproduction and
Postharvest Handling
OPerishable crops / Perishables
ODurable crops / Durables
OPre and Postharvest
Wastage/Losses

4. OWorldwide Post-harvest Losses
OPostharvest Losses in Philippines
OLoss and Quality
OObjectives in postharvest
handling/technology
OTypes of Losses
OSpecific Causes of Postharvest
Losses
OTerminologies in Postharvest

5. OPhotosynthesis Introduction
OPhotosynthesis
OChloroplast Structure
OHow do chloroplasts perform
photosynthesis?
OPhotosynthesis Summary
OImplication

6. Postharvest -derived
from the words
Post and harvest
Post -after
Harvest / Harvesting a
picking process
- the deliberate
picking of fruits,
vegetables and other
commodities

7. Postharvest
Oall the succeeding action after harvest
are defined as post-harvest technique.
From this period of time all action is
enters the process of preparation for
final consumption.

8. Eg – Pre cooling Waxing
Cleaning/washing Chemical treatment
Trimming/sorting Packaging
Curing Transportation
Grading Storage, ripening and
distribution

9. Postharvest Technology
-refers to the practices and
operations which the horticultural
produce undergo from harvest until
they are consumed or until they
reached the hand of the final
consumers.

10. Post-harvest technology / post-harvest
management
O the branch of agriculture that deals
with all the operations right from
harvesting or even the pre-harvest
stages till the commodity reaches the
consumer, either in fresh (grains, apple,
mango, tomato fruits)

11. Oor processed form (flour, juice, nectar,
ketchup) and utilization
of the wastes (pomace, peel, seed, skin etc.)
in a profitable manner (manufacture of
fermented beverages, colour extraction,
pectin extraction
etc.)

12. Function chain of Post harvest
technology
O Harvesting and preparation for market
O Curing root, tuber and bulb crops
O Packinghouse operations
O Packing and packaging materials
O Decay and insect control
O Temperature and relative humidity control
O Storage of horticultural crops
O Transportation of horticultural crops
O Handling at destination
O Packing and Packaging Practices

13. Role of Post harvest technology
1. PH Loss reduction
2. Value addition
3. Contribution to the Economy
4. Making availability of fruits and
vegetables during off seasons
5. Tools for export earnings
6. Employment generation
7. Adding variety in taste and nutrition
8. Waste utilization
9. Home scale preservation

14. Role of Post harvest
Technologist
1. To provide quality, nutritious and safe
food
2. To develop new product &
technologies
3. To develop new equipment and
determine their efficiency.

15. OHence thorough understanding of the
structure, composition, biochemistry
and physiology of horticultural produce
is essential for PH technologist.

16. Post harvest Shelf Life
O Once harvested, produce are subject to the
active process of senescence. Numerous
biochemical processes continuously change
the original composition of the produce until it
becomes unmarketable. The period during
which consumption is considered acceptable is
defined as the time of "post harvest shelf life".

17. Post harvest shelf life is typically
determined by objective methods like
OOverall appearance
OTaste, flavor, and texture of the
commodity. These methods usually
include a combination of sensory,
biochemical, mechanical, and
colorimetric(optical) measurements.

18. O is the scientific study of the physiology of
living plant tissues after they have been
denied further nutrition by picking/harvest.
OIt has direct applications to post harvest
handling in establishing the storage and
transport conditions that prolong shelf life.
Postharvest Physiology

19. Preservation and Processing
Preservation - the techniques of extending
the storage life of the produce without
deteriorating its edible quality for use.
Transpiration and respiration continue
even after harvest. This process leads to the
bio-chemical breakdown and cause
spoilage of the produce.

20. Processing
O the application of techniques to prevent losses
through preservation, processing, packaging,
storage and distribution.
O It is necessary in order to avoid glut and utilize
the surplus during the peak seasons. It
employs modern methods to extend storage
life for better distribution and also processing
technique to preserve them for utilization in
the off season.

21. OPostproduction-is the general term
applied to the handling of crops
from harvest up to the time they
reach the consumer.
Difference Between Postproduction
and Postharvest Handling

22. Postharvest handling
Ois a specific term used for the
movement of commodities and the
operations which they undergo from harvest
to the time immediately prior to meal
preparation or food processing.
OIt includes the technological aspects of
marketing and distribution.

24. slideshare.net

29. Worldwide Post-harvest Losses
OWorldwide post-harvest fruit and
vegetables losses are as high as 30
to 40% and even much higher in
some developing countries.

30. Postharvest Losses in
Philippines
O Postharvest losses of commodities in the
Philippines represent a very significant
loss of 10-50 % of production output in
developing countries( Obispo, 2016).

32. OReduction of post-harvest losses
reduces cost of production, trade
and distribution, lowers the price for
the consumer and increases the
farmer’s income.

34. Post-harvest losses occur
in terms of

35. Objectives in postharvest
handling/technology
1. to reduce or minimize postharvest
losses
2. to maintain or preserve product
quality (appearance, texture, flavor and
nutritive value)
3. to prolong or extend post-harvest life

36. Types of Losses
O Losses from physiological factors
O due to physiological and compositional changes that alter the
appearance,
O taste, texture and make produce less aesthetically desirable to end
users.
O Losses from pathological factors
O Losses from physical factors
O mechanical damage ,where it is not acceptable
for
O presentation, fresh consumption or processing.

37. Specific Causes of
Postharvest Losses
O Inappropriate maturity at harvest
OImproper harvesting method
OUnsuitable packaging materials
OPoor transport condition
OInsufficient grading
OInadequate storage facilities

38. TERMINOLOGIES IN
POSTHARVEST
OGreen life for a fruit or fruit vegetable that
ripens, this refers to the period from harvest
up to the time a fruit loses its green color
OLongevity of produce losses could be
measured in terms of the length of time a
commodity remains marketable or usable
for its intended purpose

39. OPostharvest life the period from harvest up
to the time the produce can still be used for
its intended purpose, either as food (for fruits
and vegetables) or decoration (for florist
crops).
OPost storage life time that the
commodity will last after storage
regardless of usage

40. OShelf life the time during which a commodity
that is brought to the market immediately
after harvest will stay in good condition when
displayed for sale, or stored at home prior to
use or for sale, or stored at home prior to use
or consumption
OStorage life period from start to end of any
method of commercial storage, assuming that
upon removal of the commodity from storage,
there is still time to market and use it

41. OVase life the period from the point of sale
or start of display of a cut flower or foliage
in a vase to the time when it can no longer
provide aesthetic satisfaction to the
customer.

42. Advantages of Proper Postharvest
Handling Over Increased Production in Solving
Food Needs
1. We can feed more people without bringing an additional
area / hectarage under production or without changing
present agricultural practices.
2. Preventing loss is cheaper than producing more of the
same quantity and quality.

43. 3. Improving handling practices is less
risky than improving the yield by the
addition of inputs.
4. The energy used to produce and market
food that would otherwise be lost
could be conserved.
5. More rapid in producing desired results
than increasing yield.

44. Photosynthesis
Introduction
OThe growth and development of horticultural
commodities and their quality, are greatly
affected by the process of photosynthesis.
OFruits and vegetables are generally regarded
as photosynthate sinks as they rely on energy
provided by sugars transported from leaves
(produced by photosynthesis) to carry out the
highly demanding processes of development,
maturation, and ripening.

46. Photosynthesis
O the process by which the energy
of sunlight is converted into the
energy of glucose

47. The process of photosynthesis is a
chemical reaction.
It is the most important
chemical reaction on our planet.

48. 1.The Formula:
6CO2 + 6H2O C6H12O6 + 6O2
carbon water glucose oxygen
dioxide
REACTANTS PRODUCTS
or INORGANIC INGREDIENTS
or RAW MATERIALS
sunlight
chlorophyll
enzymes
(ORGANIC )

50. Chloroplast Structure
O Found mainly in the interior tissue of leaves (aka the
mesophyll)
O Stroma- inner membrane fluid where light-
independent reactions occurs (aka the Calvin Cycle)
-here, carbon dioxide is converted into sugars
O Thylakoid-inner membranes of chloroplasts that
form stacks called grana
-light-dependent reactions occur here
-oxygen is produced here

51. Why leaves are green: interaction of light with
chloroplasts

52. How do chloroplasts perform
photosynthesis?
OWith 2 major sets of chemical
reactions:
O 1st Set of reactions are called the
LIGHT-DEPENDENT REACTIONS
(which are also called…PHOTOLYSIS or…
PHOTOCHEMICAL RXN’S)
O 2nd set of reactions are called
LIGHT-INDEPENDENT RXN’s (which are also called
the Calvin’s cycle or …Carbon Fixation)

53. 1. STEPS of LIGHT-DEPENDENT RXN’s:
- light energy is absorbed by chlorophyll.
- some of the energy is used to SPLIT WATER
into H and O.-Photolysis
- some of the energy is used to make ATP
- the O’s (oxygen) gets released into the
atmosphere.
- the H’s and some ATP are used in the next set
of reactions to make C6H12O6.
*** Takes place in the GRANA!!!

54. An overview of photosynthesis: cooperation of the light reactions and the Calvin
cycle (Layer 1)

55. An overview of photosynthesis: cooperation of the light reactions and the Calvin
cycle (Layer 2)
(Released to atmosphere)

56. 2. Steps of LIGHT-INDEPENDENT RXN’s:
- CO2 is taken in (through stomates: small
openings in the surface of leaves) from
air
& is combined with H’s from light-
dependent rxn’s to form GLUCOSE.
**This requires the use of the ATP
produced in the light-dependent
rxn’s.
**This takes place in the STROMA

57. An overview of photosynthesis: cooperation of the light reactions and the Calvin cycle
(Layer 3)

58. Photosynthesis Summary

59. 2 Stages Photosynthesis

60. Implication
O Photosynthates contribute to all
the sensory quality attributes of
horticultural commodities,
through the accumulation of
diverse metabolites such as
pigments, carbohydrates, acids,
and vitamins.

61. OThus, it is important to consider horticultural
practices needed to produce higher yield of
good-quality commodities , it require
promoting better photosynthetic activities
through diverse means such as proper tree
canopy management, sufficient leaf area, light
exposure, etc.

62. References
O Turnos, N. 2016. Postharvest lecture ppt
O Mayani,J.,C. Desai, and Vagadia,P.2016.Post
Harvest Management of Horticultural
Cropshttps://www.researchgate.net/publicatio
n/320867541
O http://ecoursesonline.iasri.res.in/mod/page/vie
w.php?id=108417
O https://www.lewispalmer.org/cms/lib/CO01900
635/Centricity/Domain/747/photosynthesis.ppt
O

63. THANK YOU AND
WASSALAM…..