Harvest Postharvest Practices Welcome Basic Harvest Postharvest Handling

Harvest & Postharvest Practices

Welcome!

Basic Harvest & Postharvest Handling Practices

Section 1 The Importance of Proper Harvesting

Different crops and crop varieties have different harvest points. Poor crop handling can lead up to 50% of loss. Deliver quality for higher market prices.

Your Role

Motto: “Know Your Crop”

Section 2 Basic Harvest and Postharvest Handling

Every crop has its correct harvesting time.

Basic Harvest & Postharvest Practices

Section 3 General Guidelines

General guidelines • • • Ensure crop is the right size and color Use the appropriate tools Clean, sort, and grade in cool, shady areas Remove contaminated products Use well-ventilated containers when transporting Avoid packing the containers one on top of each other

Fewer mistakes Increase % of good crop Increase amount of crop sold Increase in $

Postharvest Biology

Topic Areas to Be Covered Biology Basics for Harvest and Postharvest Potential Damage and Loss During Harvest and Postharvest

Section 1 Biology Basics at Harvest and Postharvest

Respiration

Fruit classification Climacteric Fruits Apple Mangosteen Non-Climacteric Fruits Black berry Lemon Avocado Papaya Cacao Okra Banana Passion fruit Cashew Pepper Rambutan Plantain Cucumber Pineapple Breadfruit Guava Mango Sour sop Tomato Eggplant Grapefruit Strawberry Watermelon Orange

Ethylene production C 2 H 4

Composition changes

Growth and development Sprouting Rooting Seed germination within produce

Water loss

Section 2 Potential Losses

Our goal is to help farmers find the causes of postharvest losses and reduce them.

Variations affect harvest & postharvest handling

Fresh produce risk

Respiration losses & other chemical changes

Losses due to physiological disorders

Freeze damage Cold damage caused by temperatures below freezing

Cold damage • Temperature • Exposure time at a given temperature

High temperature damage • Breaks down the action of enzymes • Increases the respiration rate of the plant • Affects the ability to mature

Water loss damage • Vapor Pressure Deficit, or VPD • Rate of air movement • Surface area

Mechanical damage from packing and transport

Disease damage

Group Activity: Develop a harvest/postharvest case study 1. Identify an example about working on harvest/ postharvest practices with a farmer or group of farmers. Think of it as a story that is teaching best practices about harvest and postharvest practices in the field. 2. Develop 3 learning objectives that emphasize how the case shows a farmer (or group of farmers) learning and applying best practices. 3. Develop three questions for each learning objective that would create discussion about the case. 4. Draw/write the case on easel paper and point out the main things about it.

Harvest Decisions

Topic Areas to be Covered Growth and maturity for harvesting Maturity indexes for deciding when to harvest The harvest process (packing, storage, transport)

Section 1 Maturity and Harvest

Maturity When a crop is developed enough that after harvest and postharvest management, the quality will be at an acceptable level for the final consumer.

Maturity Index - Characteristics • Objective (measurable) and not subjective • Chronological (days after transplant, after flowering) • Physical

Maturity Index Examples Time between flowering and harvest Apple, pear, banana, plantain Abscission zone development Some melons Surface morphology Grapes, tomato, cucumber, some melons Size Almost all fruits and some vegetables External color Banana, plantain, mango, broccoli, cauliflower Almost all fruits and some vegetables Sweet/sour Papaya, melon, watermelon, citrus Shape

Maturity Examples Papaya: Optimal fruit maturity for harvest and shipment; Over-mature fruit for a distant market Tomatoes: Ripening grades

Harvest • • Prepare equipment Transport product Ensure proper hygiene Practice pre-sorting

Harvest: Sweet potato Harvest can be mechanized, using a sweet potato harvester Harvest can also be manual, using a straight shovel.

Harvest: Irish potato • Harvesting with ox prevents mechanical damage. • Avoid making big piles and workers throwing the potatoes to the pile. • Avoid domestic animals in the field!

Harvest: Cassava (Yucca)

Section 2 Presorting On-Farm

Pre-sorting Identifying products that are: • Immature or overripe • Not compliant with standards • Showing mechanical damage • Showing affects of disease

In-field classification Size as required for market Physical or other damage

In-field rejection

In-field rejection Misshapen (stress) Fresh mechanical damage (harvest) Sunburn damage (green tip) Misshapen Damage (rats) Damage (nut grass)

Disease Tomato Late Blight Potato Scab

Section 3 Packing On-Farm

Field packing Traditionally farmers use sacks, but plastic crates are preferable.

Field packing and handling

Field packing and handling

Section 4 Transportation from the Farm

Transport

Transport

A note on sorting

Packaging and Storage Off-Farm

Topic Areas to Be Covered: • Packing • Storage • Specialized packing equipment and processes

Section 1 Packing Houses

Types of packing houses From sheds to large scale operations, packing house for handling fresh produce.

Minimum requirements Exterior Installation Good access to roads Adequate drainage to avoid standing water Interior Installation Good illumination to allow for grading, identification of contaminants, and protection against breakage of the lamps Materials such as wood, glass, rusty metal and cardboard are not recommended Ceiling, floor, and walls can easily be cleaned and Designed to prevent the entry of pests maintained in good condition, with curved corners, and light colored "food safe“ paint Prevent opportunity for cross-contamination with Easy to wash doors, in good condition, preferably with surroundings automatic closing, and no space between the floor Windows in good condition, with mesh to prevent dust from entering

Basic postharvest area

Practices to avoid

Commercial packhouse operations

Types of packing equipment More sophisticated equipment, including drying trays, scales, refrigerated trucks and areas for sorting and selecting produce

Section 2 Specialized Packing Equipment and Processes

Packhouse sections

Reception and delivery

Disinfection *Chlorine is banned in produce sold in the EU and is under revision by the FDA in the US

Drying and curing Best practice: Not advised: Drying yucca Curing yucca Washing potatoes in nets Potato sacks piled on the ground

Sorting and grading areas are the most critical areas in a packhouse.

Grading

Packing

Packing and weighing

Packing by size and weight Size (Example) Small Medium Large Extra Large Holland (weight) 4 - 8 oz. – 1. 0 lb. 1. 0 – 2. 0 lb. 2. 0 – 3 lb. 12 oz. Canada (Weight) 4 oz. – 1. 0 lb. 1. 0 – 2. 0 lb. Packing by size

Quality control procedures used in the packhouse must be identical to those of the buyer, especially with regards to color, blemishes, scars, etc. Packers need to be trained to prevent mistakes, repacking, and rejection by the buyers.

Storage facilities Picture shown left is example of dry storage, while the right one shows cold storage.

Loading area Ensure good access to loading area. Dispatcher must keep accurate records of product loading on trucks Usually product is counted and weighed again in this area. A final quality control check may also be done here

Section 3 Storage

Produce physiology that affects storage Respiration: • After harvesting physiological processes continue, respiration being the most important one. As a consequence of respiration energy is heat. • Total amount of heat produced = heat produced at different temperatures X time required to obtain desired temperature. Refrigeration: • Reduces the rate of respiration and metabolism. • Tropical crops are susceptible to physiological damage when exposed to temperatures below 10 o to 12 o. C.

Temperature is the environmental factor that most affects deterioration in fresh produce. • Each increment of 10 o. C above the optimum, the rate of deterioration increases 2 -3 times • Affects the production of C 2 H 4 (ethylene), germination and growth • Constant temperature is critical during storage to avoid condensation and increase in fungal and decay Cold storage is recommended for many perishable products because it helps to: • • Retard maturity, avoid changes in texture and color Reduce undesirable metabolic changes Reduce moisture loss, which results in increasing wilting Reduce the damage caused by the invasion of bacteria and fungi

Relative humidity (RH) • • The rate of water loss depends on the vapor pressure deficit between the product and the environment. This is caused by temperature and RH. Moisture in the air in storage rooms directly affects the quality of fresh produce. If its too low, the products will shrivel. If very high humidity is maintained disease problems can occur. When the air is 90 % RH at 10° C, it contains more water per unit weight than air with the same RH at 0°C.

Eythene (C 2 H 4) • Because the effects of C 2 H 4 may be desirable or undesirable, care must be taken during handling and processing. • It can be used to initiate and synchronize maturation in certain fruits but can be harmful to the quality of most non-fruit vegetables and ornamentals.

Air circulation and spacing of packed product • Air flows through the storage room at different temperatures. • Circulates through the route of least resistance. • Ensure that the positioning of boxes and pallets in storage is optimum to maximize the air flow.

Compatibility of fresh products in storage • • Consider the optimal storage conditions. Products must be compatible in temperature, relative humidity, ethylene sensitivity or production, and odor absorption.

Classification of fruits and vegetables according to sensitivity to chilling Non sensitive Sensitive Fruits Vegetables Black berry Broccoli Avocado Cucumber Grape Cabbage Banana Eggplant Kiwifruit Carrot Mango Okra Raspberry Cauliflower Papaya Squash Strawberry Celery Passion fruit Sweet potato Apple Sweet corn Pineapple Tomato Peach Lettuce Plantain Cassava

Classification of fruits and vegetables according to sensitivity to chilling Relative perishability Very high Potential shelf life (weeks) <2 High 2– 4 Moderate 4– 8 Low 8 – 16 Very low > 16 Horticultural products Blackberry, raspberry, strawberry, asparagus, broccoli, cauliflower, lettuce, sweet corn, tomato, flowers. Avocado, banana, grape, mango, honeydew, papaya, cabbage, celery, eggplant, okra, chili Apple (some varieties), grape, orange, grapefruit, lime, carrot, radish Apple (some varieties), potato, onion, garlic, squash, sweet potato Nuts

Transportation

Topic Areas to Be Covered Transportation issues in postharvest management

Field to packhouse or collection center Container selection affects quality.

Packhouse or collection center to market/buyer Distance to market is a key factor in transportation decisions.

Transporting over long distances

Types and use of containers

Transporting over long distances: Ocean Two types of container air movement: 1. Horizontal and vertical 2. Bottom to top

Preparation and cleaning of pallets in container The containers should: • Be swept and cleaned • Minimize contamination

Transport in refrigerated containers • Consider temperature & ventilation • Ensure product compatibility • Cover the open floor and pallet spaces next to the doors with plastic or carton

Transporting over long distances: Air For long-distance transportation by land, sea or air, there are various cooling systems or reefer containers that can be used.

Fintrac. com info@fintrac. com