Postharvest Practices
- 1. Postharvest Practices Kim John R. Nate MS Plant Science HORT 210 Republic of the Philippines CENTRAL BICOL STATE UNIVERSITY OF AGRICULTURE Calabanga | Pasacao | Pili | Sipocot
- 2. OUTLINE A. Trimming, Cleaning, and Removal of Excess Moisture B. Curing C. Waxing D. Standardization, Grading, and Inspection E. Ripening, Degreening, and Color Adding F. Precooling and Refrigeration G. Packaging H. Fresh Cuts
- 3. A.) TRIMMING, CLEANING, and REMOVAL OF EXCESS MOISTURE
- 4. Trimming • General term for the removal of unwanted parts • Removal of unwanted, discolored, rotten, and damaged parts
- 5. Specific Trimming Procedures • Dehanding – separation of hand and removal of stalks in banana • Deflowering – removal of floral or stylar remnants • Dethorning – removal of thorns • Topping – trimming the tops and vegetative parts • Dehusking – removal of husk • Desilking – removal of silk • Detopping – removal of crowns
- 6. Objectives of Trimming • Facilitates handling • Reduce likelihood of diseases • Minimize damage • Minimize transpiration • Retards sprouting
- 7. Objectives of Trimming Facilitates handling - caters to the demand of the consumers Examples: 1. Thorns in Roses 2. Banana Peduncle 3. Husk and silk in baby corn 4. Crown of Pineapple 5. Wrapper leaves of Cabbage
- 8. Objectives of Trimming Reduce the likelihood of diseases - removing damaged and rotten parts which may contain inoculum - Removal of floral remnants which may harbor microorganisms and pests Examples: 1. Leafy parts of onion and garlic 2. Floral remnants of Banana 3. Rotten/damaged Leaves
- 9. Objectives of Trimming Minimize damage - Other parts may puncture other fruits Example: Removal of peduncle of citrus - Other parts are kept to protect commodity Example: Retained cabbage leaves
- 10. Objectives of Trimming Minimize transpiration - Greater surface area faster and higher transpiration rate. Examples: 1. Removal of carrot leaves 2. Removal of leaves in cut flowers 3. Trimming of Taro petiole
- 11. Objectives of Trimming Retards sprouting - Removal of roots after harvesting retards sprouting
- 12. Cleaning • Removal of adhering dirt, latex, dust, insect, mold, and spray residues to improve appearance. Purpose: 1. To meet the demands of the consumers 2. To render the commodity more saleable 3. To reduce microbial load
- 13. Considerations in Appropriate Cleaning Method 1. Nature of the commodity 2. Need for maximum elimination of dirt 3. Minimum water consumption 4. Prevention of injury
- 14. Considerations in Appropriate Cleaning Method 5. Rate of cleaning output 6. Consumer demand 7. Presence of latex
- 15. Considerations in Appropriate Cleaning Method 8. Type of Commodity 9. Care in Harvesting 10. Season
- 16. Methods of Cleaning Washing - Do not use colder water - Addition of sanitizers, fungicides, sulfates Spray Washing - Uses a jet of fresh clean water Soak and Rinse - Placed in soaking tanks to loosen dirt - Rinsed in second tank
- 17. Methods of Cleaning Chemicals used for wash water Sanitizers • Chlorine • Hydrogen Peroxide • Peroxyacetic Acid • Ozone Fungicides • Thiabendazole • Imazalil • Azoxystrobin • Fosetyl Aluminium Sulfates • Aluminium potassium sulfate • Magnesium Sulfate
- 18. Methods of Cleaning Wiping - Use of cloth to remove dirt and sooty mold
- 19. Methods of Cleaning Dry Brushing - Use of brush to remove adhering dirt and insects without using water
- 20. Methods of Cleaning Forced Air - Use of pressurized air to remove dirt and insects Manual Removal - Use of hands to remove dirt
- 21. Problems in Washing Difficulty in removing latex • Water insoluble of the latex Solution: • Separate tanks for delatexing • Use of alum Prolonged washing • Reabsorption of water by the commodity Solution: • Limit soaking time • Reduce depth of wash water Spread of Microorganism • Microbial accumulation in tanks Solution: • Wash in running water • Change regularly • Trim befor washing
- 22. Water Elimination • Removal of excess surface moisture after washing or waxing • Done when commodities are wet Purpose: 1. Prevents spread and growth of microorganisms 2. Prevention of fungicide dilution
- 23. Methods of Water Elimination Drip Drying - Placing of commodities in slatted racks to drip-dried or hang-dried Use of High-Velocity Air - For high volume of commodities - For small scale, electric fans are used
- 24. Methods of Water Elimination Use of foam rollers and dry heat - Produce is passed under a series of foam rollers - Enters dry heat tunnels Dry Air in Tunnels - Produce passed under a canopy equipped with a fan and heater
- 25. B.) CURING
- 26. Curing • The process of toughening and self-healing in crops a.) bruises and skinned areas of root and tuber crops b.) reduction in moisture in citrus c.) rapid closing of the neck of bulb crops
- 27. Methods of Curing Bulb Crops 1. Solar Drying, windrowing, or sun drying 2. Air or cold curing 3. Forced heated-air curing
- 28. Curing Citrus • Healing of wound via lignification • Fruits are held in open racks • Different curing temperatures and period Pummelo : Room Temperature for 1-2 weeks Mandarin: 30°C for 3-5 days
- 29. Curing Root and Tuber Crops • Outdoor curing • Stacked and covered with materials like canvass or woven grass matts
- 30. Factors Affecting Curing Temperature • Optimum temperature is higher than the normal temperature of the crop • Faster rate of wound healing at higher temperature • Extreme temperature can delay curing (<35°C and >12°C)
- 31. Factors Affecting Curing Relative Humidity • High RH for root crops (80-95%) • Low RH for bulb crops (60-70%) Gases • Carbon dioxide levels at 10% or more, and oxygen below 5% inhibits curing • Periderm is not formed at anaerobic conditions
- 32. Factors Affecting Curing Type of Damage • Smooth cuts heal faster than other wounds • Ragged wounds causes longer curing period • Compression and impact damage can inhibit periderm formation Length of Period After Harvest • Wound healing is quick on freshly harvested commodities • Wounds incurred after storage in root crops heal slowly
- 33. C.) WAXING
- 34. Waxing • Application of thin film of surface coating to fruits and vegetables Purpose: • Intended to replace the natural coating of the commodity which is removed during handling, or supplement it.
- 35. Appropriate Coatings • Transparent • Glossy • Odourless • Tasteless • Biodegradable • Safe • Sufficient permeability to gas and impermeable to semi-impermeable to water
- 36. Materials for Wax Formulations • Lipids • Resins • Polysaccharide-based coatings • Proteins • Composite and Bilayer coatings
- 37. Effects of Waxing • Reduces moisture loss • Maintains or enhances natural gloss • Slows down respiration rate and ripening process • Carriers for inhibitors for senescence and sprouting • Carriers of fungicides and colorants • Seals tiny scratches and injuries • Reduces chilling injury in some crops
- 38. Methods of Waxing • Dipping • Foam Waxing • Spray Waxing • Slab or brush method • Drip Method • Controlled drop application
- 39. D.) STANDARDIZATION, GRADING and INSPECTION
- 40. Grading • The process of classifying the produce into groups according to a set of criteria of quality and size recognized or accepted by the industry • Grades are the names of the groups under which produce are classified Example: Extra Class, Class I, Class II
- 41. Grading • Sorting – Process of classifying produce into groups designated by the person classifying them according to whatever criteria they desire. • Sizing – classification of produce according to sizes Size Classifications: Small, Medium, and Large
- 42. Benefits of Grading • For consumers – assurance of quality • For Farmers – sound basis for pricing • For cooperatives – fairness in the sale of pooled produce • For processors – eliminates sorting by processor • For traders – establish business confidence
- 43. Benefits of Grading • For buyers and sellers – provides common language in buying and selling • For truck-buyers – incur less damage • For courts – facilitates settlements of disputes between contracting parties • For banks – establish loan value for produce • For the general public – provides good price comparison
- 44. Standardization • The process of formulation and issuing grade standards. • Grade standards • Product standard or standard itself • Set of criteria and specifications of quality determining grades. • Standards describe the characteristics of produce such as: • Maturity • Color • Cleanliness • Shape • Freedom from decay and blemishes • Uniformity
- 45. Characteristic of a Good Standard • Acceptable – Represents the consensus of opinions of participating body • Understandable – clear, unambiguous and easy to understand • Appropriate – applicable to commercial varieties sold
- 46. Quality Criteria • Appearance – external condition • Stage of Maturity and Ripeness – commercial maturity • Texture – finger feel and mouth feel • Damage or Defect – any imperfection, deficiency, flaw • Safety and Wholesomeness – being clean and free from harmful contaminants
- 47. Inspection • The process of measuring, examining, and testing samples to determine whether the grade standard is have been interpreted or appropriately enforced. Types: • Continuous Inspection – frequent inspection in the packing line • Inspection on a sampling basis – randomly selects representative samples
- 50. E.) RIPENING, DEGREENING and COLOR ADDING
- 51. Ripening • Series of biochemical and physical processes that cause an immature fruit to develop all the desirable characteristics of its species • Ethylene in the hormone that is responsible in the ripening process
- 52. Ripening Climacteric Fruits • Fruits that can be picked at green mature stage which can be subsequently ripened Non-climacteric Fruits • Fruits that need to be picked at the ripe stage
- 53. Advantages of Ripening Regulation • Allows shipment of green mature fruits • Better color development • Slower disease symptom expression • Less fruit shrivelling • Faster means of getting cash • Takes advantage of transient prices • Flexibility of selling • Efficient use of space
- 54. Degreening • Treatment with ethylene to improve the color of non- climacteric fruit Examples: Local oranges treated with ethylene develop the orange coloration
- 55. Ripening and Degreening Techniques Introduction of Ethylene or acetylene to the environment of the fruit • Ethylene • Acetylene • Bioethylene Induce stress ethylene production • Wounding fruit • Plasmolysis
- 56. Ripening and Degreening Requirements Fruit Condition • Fruits should be mature enough Room Condition • Uniformly low temperature • Uniformly high humidity • Good air circulation • Air tight
- 58. Color Adding • Application of dye to pale-colored commodities to improve their color • Done when degreened fruits do not produce desired color intensity
- 59. Tinting • Application of dye to white cut-flowers • Done when flowers of a particular color are not available Methods Contact Tinting – dipping into dye solution for 4-8 seconds Systemic Tinting – placing of the recut stem of cut flowers into the dye solution
- 60. F.) PRECOOLING
- 61. Precooling • Rapid cooling of the commodity to a desired temperature soon after harvest before it is stored or transported. Objective: • To bring down the temperature of the commodity to the optimum level as rapidly as possible without inducing physiological disorders or physical damage
- 62. Benefits of Precooling • Excellent quality of produce is maximized • Minimizes refrigeration load • Allows ripe fruit to be transported or stored
- 63. Methods of Precooling • Room Cooling • Forced Air Cooling • Hydrocooling • Vacuum Cooling • Icing
- 64. G. PACKAGING
- 65. Packaging • Art, science, and technology of bringing goods from their source to the place of consumption at the minimum cost possible Functions of a package: • Facilitate easy handling • Protects produce • Sells the produce • Informs the consumer
- 66. Kinds of Packaging • According to material • burlap, fibrous materials, wood, paper sheets, plastics • According to protective capacity • Flexible, semi-rigid • According to design • Bags and sacks, baskets, crates, and boxes • According to Storability • Stackable, nestable, collapsible • According to returnability • One-trip containers, returnable
- 67. G. FRESH CUTS
- 68. Fresh Cut • Preparation and handling cut up fruits and vegetables Types of Fresh Cuts 1. Ready to Cook 2. Ready to Eat 3. Ready to Process
- 69. Advantage of Fresh Cuts • Households • Convenience • Food Service Establishments • Better portion control • Processors • Greater recovery of good quality ready-to-process raw materials • Exporters • Minimized quarantine problem
- 70. References • Bautista, O.K. and Esguerra, E.B. 2007. Trimming, cleaning, and removal of excess moisture. Postharvest Technology for Southeast Asian Perishable Crops 2nd Edition. University of the Philippines Los Baños. • Esguerra, E.B. and Bautista, O.K. 2007. Waxing. Postharvest Technology for Southeast Asian Perishable Crops 2nd Edition. University of the Philippines Los Baños. • Agravante J.U. and Bautista O.K. 2007. Standardization, grading, and inspection. Postharvest Technology for Southeast Asian Perishable Crops 2nd Edition. University of the Philippines Los Baños. • Agravante J.U. and Bautista O.K. 2007. Packaging. Postharvest Technology for Southeast Asian Perishable Crops 2nd Edition. University of the Philippines Los Baños. • Rimando, T.J., Bautista, O.K., Esguerra, E.B. 2007. Ripening, degreening and color adding. Postharvest Technology for Southeast Asian Perishable Crops 2nd Edition. University of the Philippines Los Baños. • Flor, N.B., Esguerra, E.B., Masilungan, G.D. 2007. Preparation and handling of fresh cuts. Postharvest Technology for Southeast Asian Perishable Crops 2nd Edition. University of the Philippines Los Baños.
- 71. Thank you!