Post Harvest Management for Fresh Fruits, Vegetables and Root Crops – A Guide for Farmers
There are two main functions of Post Harvest Management:
- To maintain the good quality of the harvested produce for the market.
- To reduce the level of losses in weight and quality after harvest
As a result the shelf/storage life of the produce is extended.
Estimates of Post Harvest losses from the field to the market in the following types of produce are as follows:
Leafy vegetables - 50 %
Green Peas/Beans - 30-50 %
Fruits - 20-40%
Root Crops - 10-20%
Dried Products - 5-10%
The level of loss is related to the part of the plant the product represents and therefore its life sustaining (physiological) functions that continue after harvest.
Causes of Post Harvest Losses:
- Improper harvesting
- Poor handling of the produce from the field through to the market place
- Inappropriate container and use of packaging material
- Poor storage conditions
- Poor transportation and distribution system
- Lack of adequate and appropriate storage facilities
The golden rule of Post Harvest Management is- “QUALITY CANNOT BE IMPROVED AFTER HARVEST BUT MAINTAINED”...
Therefore only good quality produce must be prepared for market.
Poor quality produce will have a short Post Harvest life.
However, the quality, condition and the ability to market fresh produce can be greatly improved by the farmer carrying out proper cultural practices.
- Select appropriate field site.
- Use improved seeds.
- Use seed trays to sow seeds as this saves on expensive seeds and improves germination potential.
- Plant in rows as it is easier to tend and harvest with minimum damage to crops.
- Use cultural practices that will reduce the incidence of disease/pests e.g. crop rotation, time of planting etc.
- Use the type and correct quantity of chemicals recommended for plant protection.
Proper Post Harvest Management Practices:
Produce must be harvested without any form of damage and under certain conditions in order to maintain its good quality and prevent spoilage.
Factors to consider:
Maturity of the Produce
The maturity speaks to the ideal condition for consumption.
Features used to judge the best quality produce include: shape, colour, texture,
Smell and resonance (sound when tapped).
Widening of segments (breadfruits, soursop), and drying of the aerial part of the plant
(yam, dasheen, onion).
Immature produce has a short post harvest life.
Time of day to reap?
- All fresh produce must be reaped in the cool of the day to reduce excessive moisture loss and wilting.
- Most crops are freshest and turgid early in the morning.
- Harvesting in the middle of the day should be avoided.
- Night reaping is expensive.
- Produce should not be harvested wet with dew or early morning rain as when packed, this can lead to spoilage.
Harvesting Tools and Methods
The use of proper tools will prevent unnecessary injury to the produce being harvested.
It is recommended by RADA that the use of picking poles with bag be employed or climbing and picking by hand to prevent fruits from falling to the ground.
Use of short sharp knives for cutting stems and trimming in the field, is recommended. Outer protective leaves of some types should be left to protect the product through to market.
Root Tubers and Bulbs
These can be pulled out of the ground if the soil is loose, or use of digging sticks used to remove the soil, or a fork being placed far from the root to loosen the soil and lever the tuber up out of the soil.
Selection and Grading
The produce must be sorted and graded based on its market quality and the market source.
They are usually separated into two or three grades.
The best quality is grade one, those with defects is placed in the grade two and the poorest quality placed in grade three.
Grading assists with pricing as grade one produce receives the highest price when compared with grade three.
The quality/grade needed by the market must be determined before sale.
Farm produce are packaged for four main reasons:
- To protect the produce against rough handling during loading and unloading and transport
- To contain the produce as an efficient unit that is easy to handle and that can be marketed as a unit
- To communicate with the buyer by the way of a label therefore advertising and marketing the product via a trade mark or a trade name
- To market the produce as the package will improve its presentation to the buyer and provide a standard package that will lead to efficiency in the market place
However, the type of packaging used can account for 15 to 20 percent of post harvest loss in fresh produce.
Recommended packaging materials are:
- Perforated plastic bags for pre-packaged vegetables and fruits for the retail market
- Ventilated plastic crates to transport large volumes of fruits and vegetables
- Solid black crates and polypropylene (fertilizer type) bags to transport root crops and green unripe fruits.
The disadvantages in using polypropylene bags to transport leafy vegetables and ripe fruits are:
The product is crushed due to the large amount placed in the bags
The temperature and humidity in the bags increase and so the product begins to spoil
Fresh fruits and vegetables spoil quickly at room temperature (27-33 degrees C), therefore the need to sell them as soon as they are reaped.
They can be stored for longer periods under cold storage conditions but that is expensive.
Some recommended storages practices are:
- Store only good quality crops: clean, mature, free from disease and injury.
- The sooner the fruits and vegetables are stored after harvest, the longer their storage life.
- Do not mix fruits and vegetables of different kinds in the same store room, and ensure good ventilation.
- Make sure that the containers and the storage rooms are clean to prevent contamination and spoilage of the produce.
- Store produce such that inspection can occur from time to time to remove spoilt items or produce for sale.
- Cold storage temperatures vary between 7 -15 degrees C for most fresh fruits and vegetables but some root crops and bulbs are stored in drier conditions and at higher temperatures.
- Improper transportation methods can result in 10 to 20 percent post harvest loss in fresh produce. Therefore certain minimum requirements are necessary to maintain quality and reduce loss.
- The vehicle must not be overloaded and the load must be stable and well ventilated.
- During transportation, the produce must be protected against sun, rain and dust by covering it with a light colored tarpaulin or enclosing it in a refrigerators truck
- Excessive speeding, sudden stops and jerk starts must be avoided, as they will cause squeezing and bruising of the product
- Poor roads, uneven surfaces, pot holes, winding corners will all greatly increase mechanical damage unless adequate care is taken.
- Loading and unloading of produce must be done with care. Packed produce must not be thrown from any vehicle.
Palletizing packaged produce results in the surety that good quality produce arrives in the marketplace in good condition.
Proper Post Harvest management practices will therefore result in reduction of food loss and maintenance of quality.
Quality assurance is therefore guaranteed with increased income.
Information produced by the RADA Division of Technology, Training and technical Information.
Further information can be had from the Rural Agricultural Development Authority (RADA) by calling 1-888-ASK-RADA or by logging on to www.rada.gov.jm.