This presentation covers the principles and practices of harvesting and post-harvest handling of vegetable crops, focusing on maturity indices, harvesting methods, post-harvest operations, and marketing. Emphasis is placed on maintaining crop quality, minimizing post-harvest losses, and optimizing economic returns. Key concepts include maturity indices, post-harvest handling, sorting and grading, storage, and marketing systems.
Introduction to Harvesting and Post-Harvest Handling
- Harvesting: Gathering mature crops from the field.
- Post-harvest handling: Operations after harvest to maintain quality and reduce losses.
- Proper techniques are essential for quality, shelf-life, and profitability.
Maturity and Maturity Indices
- Maturity: Stage when a crop is ready for harvest.
- Maturity indices: Observable signs indicating readiness for harvest.
- Indices include color, size, shape, texture, weight, and composition.
Maturity Indices of Selected Vegetables
| Vegetable |
Maturity Index |
| Potato |
Culm yellow and dry; skin does not slip easily. |
| Cabbage |
Compact head; firm when pressed. |
| Cauliflower |
Compact, creamy-white curd; no discoloration. |
| Sweet corn |
Kernels exude milky sap when pierced. |
| Lettuce, Mustard, Pechay |
Well-developed, green leaves; not yellowing. |
| Sweet pepper |
Full size, firm, deep color. |
| Radish |
Large, firm, crispy roots; not pithy. |
| Tomato |
Green for distant markets; breaker to ripe for local. |
Types of Maturity
- Physiological maturity: Crop has completed development; ripening begins.
- Commercial maturity: Harvest stage based on market or processing needs.
- Harvest timing may differ based on intended use.
Methods of Determining Maturity
- Visual method: Color, size, shape, abscission zones.
- Feel method: Firmness, crispness, texture by touch.
- Chemical analysis: Sugar, acid, starch content.
- Physical means: Pressure tester, specific gravity.
- Computation method: Days from planting or flowering to harvest.
Preparations Prior to Harvesting
- Inspect fields for crop readiness and remove obstructions.
- Prepare harvesting tools and materials.
- Construct temporary sheds for harvested produce.
- Avoid exposing harvested crops to sunlight.
Harvesting Tools and Materials
- Use appropriate tools: scissors, pruning shears, knives.
- Proper tools reduce damage and maintain quality.
Considerations During Harvesting
- Harvest at optimal time of day (e.g., morning or late afternoon).
- Harvest at proper maturity for intended use.
- Avoid sun exposure to prevent wilting and sunscald.
- Handle produce gently to prevent mechanical injury.
- Avoid deep piling to prevent crushing and heat buildup.
Post-Harvest Handling: Key Operations
- Trimming and cleaning: Remove damaged or diseased parts.
- Sorting and grading: Classify by size, shape, color, and quality.
- Drying and curing: For tubers and bulbs to heal wounds.
- Proper storage: Maintain suitable temperature and humidity.
Mechanical and Physiological Damages
- Mechanical injuries: Cuts, abrasions, bruises during harvest/handling.
- Physiological losses: Yellowing, wilting, sprouting, toughening.
- Both types reduce quality and market value.
Cleaning and Trimming the Harvest
- Cleaning removes soil, dirt, and residues.
- Wiping with a soft cloth is preferred for some vegetables.
- Trimming removes undesirable, damaged, or diseased parts.
- Improves appearance and reduces transport costs.
Sorting and Grading
- Sorting: Grouping by industry or consumer standards.
- Grading: Classifying by color, size, shape, maturity, defects.
- Grades: Fancy, No. 1, 2, 3, 4, or off-grade.
- Honest grading enhances market value and reputation.
Packing and Packaging
- Packing: Placing produce in suitable containers for transport/storage.
- Use crates (wooden/plastic) with liners to prevent injury.
- Do not mix different grades in one container.
- Proper packing reduces losses and maintains quality.
Curing and Storage
- Curing: Exposing tubers/roots to warm, humid conditions to heal wounds.
- Recommended for potatoes, sweet potatoes, onions (15–19°C, high RH).
- Storage: Delays sale/distribution; controls supply and stabilizes price.
- Not all vegetables are suitable for long-term storage.
Transporting Harvested Produce
- Transport from farm to market must minimize damage.
- Avoid throwing, trampling, or overloading containers.
- Proper loading preserves quality and reduces losses.
Causes of Post-Harvest Losses
- Technological: Decay, yellowing, wilting, rotting, sprouting.
- Mechanical: Cuts, punctures, cracks, abrasions from poor handling.
- Non-technological: Lack of storage, transport, adverse weather, market demand.
- Microbial decay often follows mechanical or physiological damage.
Signs of Deterioration in Vegetables
| Vegetable |
Sign of Deterioration |
| Leafy vegetables |
Yellowing |
| Cauliflower, Broccoli |
Opening florets, softening |
| Sweet corn |
Loss of sweetness |
| Okra |
Softening |
| Cucumber |
Yellowing |
| Beans |
Toughening, yellowing |
| Chayote, Tomato, Pepper |
Seed germination |
| Asparagus |
Elongation, feathering |
| Onion, Garlic, Sweet potato, Ginger |
Sprouting, rooting |
| Carrot |
Softening |
Marketing of Vegetable Products
- Marketing: Transfer of goods from producer to consumer.
- Types: Local market, nearby town market, wider regional/national markets.
- Freshness is crucial for leafy and perishable vegetables.
Methods of Marketing
- Retailing directly to consumers: Farmer sells in local markets.
- Selling to middlemen/wholesalers: Middlemen harvest and market crops.
- Selling at the farm: Direct negotiation with buyers.
- Selling through contracting companies: Pre-agreed contracts specify terms.
- Selling through cooperatives: Collective marketing for better returns.
Farm Records and Accounts
- Farm records: Written statements of facts and figures for management.
- Farm accounts: Financial statements tracking income and expenses.
- Essential for monitoring financial status and decision-making.
Classification of Costs in Vegetable Production
- Fixed costs: Incurred regardless of production (e.g., land tax, equipment depreciation).
- Variable costs: Change with production (e.g., seeds, fertilizers, labor).
- Cash costs: Actual money spent (e.g., hired labor, inputs).
- Non-cash costs: Family labor, own capital interest.
Computation of Net Income
- Gross income = Quantity produced × Price per unit.
- Total cost = Fixed costs + Variable costs.
- Net income = Gross income – Total cost.
Summary: Best Practices in Harvesting and Post-Harvest Handling
- Harvest at correct maturity using appropriate indices.
- Handle produce gently to avoid mechanical damage.
- Sort, grade, and pack properly for market requirements.
- Use suitable storage and transport methods to minimize losses.
- Maintain accurate records for better farm management.
Objective Questions
Q1. Which of the following is NOT a maturity index for vegetable crops?
A. Aroma
B. Color
C. Weight
D. Texture
Answer: A
Q2. What is the recommended method for checking if a green tomato is mature?
A. Smell the fruit
B. Slice and check if seeds slip away from the knife
C. Weigh the fruit
D. Check for yellowing of the skin
Answer: B
Q3. Which method is used to measure the softness of a fruit during maturity determination?
A. Visual method
B. Chemical analysis
C. Pressure tester
D. Computation method
Answer: C
Q4. What is the main purpose of curing newly dug tubers or roots?
A. Increase sweetness
B. Heal bruised or wounded produce
C. Reduce weight
D. Enhance color
Answer: B
Q5. Which of the following is considered a physiological loss in vegetables?
A. Cuts and abrasions
B. Yellowing and toughening of beans
C. Cracks and splits
D. Abrasion of outer covering
Answer: B
Q6. Which packing material is now commonly used for trading vegetable products?
A. Metal boxes
B. Polyethylene bags
C. Glass jars
D. Paper sacks
Answer: B
Q7. What is the main cause of sunscald in harvested tomatoes and peppers?
A. Exposure to rain
B. Exposure to sunlight
C. Exposure to cold
D. Exposure to wind
Answer: B
Q8. Which marketing method assures the farmer of a ready market and relieves him of many risks?
A. Retailing directly to consumers
B. Selling to middlemen or wholesalers
C. Selling in the farm
D. Selling through cooperatives
Answer: B
Q9. Which of the following is a fixed, non-cash cost in vegetable production?
A. Hired labor
B. Land tax
C. Care of implements
D. Seeds
Answer: C
Q10. To compute net income from vegetable production, which of the following is subtracted from gross income?
A. Only fixed costs
B. Only variable costs
C. Total cost of production
D. Total cost of marketing
Answer: C
