What is post harvest technology

postharvest

1. What is post harvest technology
Dr. Majid Javanmard(Ph.D)
Food Hygiene & Quality Control

2. Horticulture Production: Global Trends
Theworldpopulationwouldtopeightbillionbytheyear2030(FAO)
FAOestimatedthattheworldproductionoffruitsandvegetablesoverathree-
yearperiodwas489milliontonsforvegetablesand448milliontonsforfruits.
Thistrendinproductionisexpectedtoincreaseatarateof3.2percentper
yearforvegetablesand1.6percentperyearforfruits.
Asiaistheleadingproducerofvegetableswitha61percenttotalvolume
outputandayearlygrowthof51percent.
theU.S.continuestoleadintheexportoffreshfruitsandvegetables
worldwidewithorange,grapes,andtomatoes.
Brazildominatestheinternationaltradeoffrozenorangejuiceconcentrate,
whileChilehasbecomethemajorfreshfruitexporterwithaproduction
volumeof45percent.
Thetopsixfruitproducers,indecliningorderofimportance,areChina,India,
Brazil,USA,Italy,andMexico.China,India,andBrazilaccountforalmost30
percentoftheworld'sfruitsupply

3. TRADITIONAL CONSUMPTION
Fruitandvegetableconsumptionpercapitashowedanincreaseof0.38
percentforfreshfruitsand0.92percentforvegetablespercapitafrom1986to
1995.
ThehighestconsumptionoffreshfruitswasregisteredinChina(6.4%),asthe
apparentpercapitaconsumptionofvegetablesinChinawentfrom68.7kgper
capitain1986to146kgin1995(53.8%growthrate),whileAfricanandNear
EastAsiancountriesshowedadecreaseinfreshfruitconsumption.
ThelowestconsumptionofvegetablespercapitawasregisteredinSub-
SaharanAfrica.

4. post harvest
In agriculture, postharvesthandling 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. Postharvest
treatment largely determines final quality, whether a crop is
sold for freshconsumption, or used as an ingredient in a
processed foodproduct.
The most important goals of post-harvest handling are
keeping the product cool, to avoid moisture loss and slow
down undesirable chemicalchanges, and avoiding physical
damage such as bruising, to delay spoilage.
Sanitationis also an important factor, to reduce the
possibility of pathogensthat could be carried by fresh
produce, for example, as residue from contaminatedwashing
water.

5. After the field, post-harvest processing is usually
continued in a packing house. This can be a simple
shed, providing shade and running water, or a large-
scale, sophisticated, mechanizedfacility, with
conveyor belts, automatedsorting and packing
stations, walk-in coolersand the like. In
mechanized harvesting, processing may also begin
as part of the actual harvest process, with initial
cleaning and sorting performed by the harvesting
machinery.
Initial post-harvest storage conditions are critical
to maintaining quality. Each crop has an optimum
range for storage temperature and humidity. Also,
certain crops cannot be effectively stored together,
as unwanted chemical interactions can result.
Various methods of high-speed cooling, and
sophisticated refrigeratedand atmosphere-
controlled environments, are employed to prolong
freshness, particularly in large-scale operations.

6. Regardless of the scale of harvest, from
domestic garden to industrialized farm,
the basic principles of post-harvest
handling for most crops are the same:
handle with care to avoid damage
(cutting, crushing, bruising), cool
immediately and maintain in cool
conditions, and cull (remove damaged
items).


7. Postharvest Shelf Life
Once harvested, vegetable and fruit are subject
to the active process of senescence. Numerous
biochemical processescontinuously change the
original composition of the cropuntil it becomes
unmarketable. The period during which
consumption is considered acceptable is defined
as the time of "postharvest shelf life".
Postharvest shelf life is typically determined by
objective methods that determine the overall
appearance, taste, flavor, and texture of the
commodity. These methods usually include a
combination of sensorial, biochemical,
mechanical, and colorimetric(optical)
measurements.
A recent study attempted (and failed) to discover
a biochemical markerand fingerprint methodsas
indices for freshness

8. Postharvest Physiology
Postharvestphysiologyisthescientificstudyofthe
physiologyoflivingplanttissuesaftertheyhavedenied
furthernutritionbypicking.Ithasdirectapplicationsto
postharvesthandlinginestablishingthestorageand
transportconditionsthatbestprolongshelflife.
Anexampleoftheimportanceofthefieldtopost-
harvesthandlingisthediscoverythatripeningoffruit
canbedelayed,andthustheirstorageprolonged,by
preventingfruittissuerespiration.Thisinsightallowed
scientiststobringtobeartheirknowledgeofthe
fundamentalprinciplesandmechanismsofrespiration,
leadingtopost-harveststoragetechniquessuchascold
storage,gaseousstorage,andwaxyskincoatings.
Anotherwellknownexampleisthefindingthatripening
maybebroughtonbytreatmentwithethylene.

9. Post-harvesttechnologyinvolvesall
treatmentsorprocessesthatoccurfrom
timeofharvestinguntilthefoodstuff
reachesthefinalconsumer.
Efficienttechniquesforharvesting,
conveying/transportation, handling,
storage, processing/preservation,
packaging,etcarecomponentsofthepost-
harvestchain.
Harvestingisnormallyincludedasa
componentofthealthoughpost-harvest
strictlymeans'afterharvest'becausehow
produceareharvestedhavealargebearing
onthepost-harvestlifeoftheproduce.

10. Post harvest technology is inter-disciplinary
"Science and Technique" applied to agricultural
produce after harvest for its protection,
conservation, processing, packaging, distribution,
marketing, and utilization to meet the food and
nutritional requirements of the people in relation
to their needs.
Importance of Post-harvest technology lies in the
fact that it has capability to meet food
requirement of growing population by eliminating
avoidable losses making more nutritive food items
from low grade raw commodity by proper
processing and fortification, diverting portion of
food material being fed to cattle by way of
processing and fortifying low grade food and
organic wastes and by-products into nutritive
animal feed.

11. Post-harvest technology has potential to
create rural industries. In India, where 80
percent of people live in the villages and 70
percent depend on agriculture have
experienced that the process of
industrialization has shifted the food, feed
and fibreindustries to urban areas.
The purpose of post harvest processing is
to maintain or enhance quality of the
products and make it readily marketable.


12. Post Harvest Industries
The post harvest industry includes the following main components
Harvesting and threshing
Drying and storage
Processing (conservation and / or transformation of the produce)
Utilization by consumer including home processing.

13. Other components of the system include.
Transportation and distribution.
Marketing.
Grading and quality control.
Pest control.
Packaging.
Communication among all concerned.
Information, demonstration and advisory systems.
Manufacture and supply of essential equipment and machinery.
Financial control.
Price stabilization
Management and integration of the total system.