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.