Introduction

This module delves into the fundamental principles of storage in post-harvest management. Effective storage is crucial for minimizing losses, maintaining nutritional quality, and extending the availability of agricultural produce1. Understanding these principles allows for the implementation of appropriate storage methods to preserve the quality and marketability of fruits and vegetables.

1. Role of Post-Harvest Management in Storage

• Minimizing Spoilage: Post-harvest management significantly boosts food availability by minimizing the spoilage of perishable fruits and vegetables1.
• Maintaining Nutritional Security: Proper storage and handling minimize nutrient loss, ensuring that the population has access to nutritious food1.
• Extending Shelf Life: Techniques such as proper handling, packaging, cold storage, and advanced technologies extend the shelf life of produce beyond short harvest seasons1.

2. Essential Principles for Extending Storage Life

• Minimizing Undesirable Plant Processes: Focus on minimizing the rate of processes such as sprouting, rooting, and greening in stored fruits and vegetables1.
• Temperature and Humidity Control: Effective storage conditions, such as temperature and humidity control, are crucial to reducing transpiration and respiration rates1.
• Proper Packaging: Packaging protects harvested products and can also be informative12. Containers need vents for air flow and cooling2.
• Controlled Atmospheres: Protective coatings and controlled atmospheres can further help in extending shelf life and maintaining the quality of produce1.

3. Key Factors Impacting Storage Life

• Temperature: Lowering product temperature is the most important way to reduce deterioration rate2. Decreasing the temperature reduces the product’s metabolism (respiration and ethylene production), water loss, and the growth of decay-causing fungi and bacteria2.
• Relative Humidity: Maintain proper relative humidity to control water loss3. Most crops are ideally stored at higher RH (90-100%) to prevent water evaporation into the air leading to water loss3.
• Atmospheric Composition: Reduced oxygen and elevated carbon dioxide levels can also affect storage longevity1.
• Physiological State: The physiological state of the produce influences storage life1.
• Pre-Harvest Conditions: Climatic conditions, cultural practices, and the genetic makeup of the plant significantly impact the storage potential of produce1.
• Harvesting Techniques: Proper harvesting techniques can minimize physical damage13.
• Initial Physical State: The initial physical state of the produce is an important factor1.

4. Managing Undesirable Processes During Storage

• Controlling Sprouting, Rooting, and Greening: Achieved by managing storage conditions, such as temperature and humidity, and employing techniques like proper packaging and protective coatings1.
• Reducing Water Loss and Respiration: High relative humidity and low temperatures help reduce water loss, while proper ventilation prevents the build-up of heat and gases that accelerate spoilage1.
• Ethylene Control: Minimizing ethylene in storage may be necessary for more ethylene-sensitive crops, especially when storing different crops in the same cooler for extended periods. Ventilation can reduce the ethylene levels in storage3.

5. Minimizing Damage and Contamination

• Reducing Injuries: Reduce the physical handling to a minimum; every time the product is handled, it is damaged2.
• Protecting Product: Protect the harvested product from the sun; bring it rapidly from the field/exposed area to the packing station and keep out of the direct sun2.
• Cleanliness and Sanitation: Keep the packing line as simple as possible and keep it clean2. If water is used, use clean water or a sanitizer if the water is reused2.
• Sorting and Culling: Sorting allows for different sizes and grades of product to be stored and sold separately and culling can separate damaged or lower quality product from the main lot3.

6. Different Storage Methods

• Natural Storage: Keeping produce in situ or in simple structures like pits and trenches1.
• Artificial Storage: Includes refrigerated and ventilated storage, uses mechanical or chemical methods to maintain optimal conditions1.
• Low-Cost Storage Structures: Clamps and zero energy cool chambers provide affordable options1.
• Advanced Methods: Controlled atmosphere storage offer precise control over storage conditions1.

Conclusion

Understanding and applying these storage principles is essential for minimizing post-harvest losses and ensuring the availability of high-quality produce1. By carefully managing temperature, humidity, atmospheric composition, and handling practices, the storage life and nutritional value of fruits and vegetables can be significantly extended