Chapter 11 Basic Handling Requirements for Air Exports of Perishable Produce from South Africa

1. General Comments

Airfreight of perishable products faces several specific challenges that must be addressed to ensure good arrival condition at the lowest possible cost. Key complicating factors include:

• High perishability: Most produce offered for airfreight is highly perishable with a short shelf life.
• High delivery temperatures: Produce is often delivered very warm (over 25°C) to the air cargo terminal.
• Limited terminal facilities: Cargo terminals cannot store every product at its optimum temperature.
• Exposure to heat: Due to airline procedures, products may stand for up to three hours in the sun before loading, especially in summer, causing temperature increases and reduced shelf life. It is recommended to use forwarding agents who employ insulated “silver blankets” to minimize temperature rise during handling and loading.
• Suboptimal airline handling: Airline cargo handling procedures do not support optimum handling of perishables.
• No in-flight temperature control: Cargo space temperatures cannot be controlled during most commercial flights.
• Misconceptions in the supply chain: Some believe temperature management is unnecessary because the product will reach the market the next day. This is incorrect; all perishable cargo enters the same distribution channel.

The requirements and recommendations in this chapter are based on years of experience with airfreight of perishable products from South Africa. While previous chapters focused on sea shipments, most concepts also apply to air export. Key requirements include:

• Product quality certification according to the Minimum Standards prescribed by the RSA National Department of Agriculture (see Chapter 1).
• Food safety and traceability according to national and international specifications (see Chapter 1).
• Cold store registration, instrumentation, and temperature measurement (see Chapter 2).
• Cargo preparation, including specifications for refrigerated road transport (see Chapter 3), cold chain maintenance (see Chapter 6), and optimum product storage conditions (see Chapter 8).

2. Packaging for Air Export

Packaging materials and methods for airfreight must be of the same or even higher standard than for sea export, even though the product is usually marketed within a few days. Special attention must be given to:

• Strength: Packaging must withstand lateral and vertical forces during takeoff and landing, which can be up to nine times greater than for sea freight.
• Humidity and condensation: Airfreight cargo is more exposed to temperature and humidity changes, leading to condensation. Free water on packaging can reduce carton strength and stability.
• Handling and loading: Loading into non-square airfreight containers and aircraft spaces is not always optimal, resulting in cartons being squashed in all directions.
• Precooling: The forwarding agent must ensure products are precooled to the optimum temperature before loading.

3. Precooling for Air Export

• The optimum product temperature is determined by the product, not the transport mode.
• Products must be precooled to the optimum temperature (see Chapter 8) before dispatch under refrigeration to the airport.
• Research and experience confirm that properly precooled produce arrives much colder than non-precooled produce.
• The same principles for temperature set point, air circulation, precooling times, and product temperature apply for both sea and air freight.

4. Transport to the Airport

• Remove field heat by precooling before refrigerated transport to the airport.
• Minimize temperature increases during transport.
• Use refrigerated vehicles whenever possible (see Chapter 3).
• If refrigerated transport is impractical, use insulated transport to maintain temperature and minimize condensation.
• Open truck transport is not recommended due to exposure to the elements and contamination risks.
• Non-palletised cargo must be handled and transported with utmost care.

5. Handling and Storage at the Air Cargo Terminal

5.1 Cargo Mixes and Taints

• Cross-tainting occurs rapidly and must be prevented.
• Where multiple cold storage spaces exist, refer to compatibility tables (see Chapter 8).
• Store products to prevent cross-tainting or temperature injury while awaiting aircraft loading.
• Only temperature- and taint-compatible products should be placed in the same airfreight container.
• Containers must be absolutely clean; remains of previous cargo can contaminate and taint perishable produce.

5.2 Temperature Requirements and Compromises

• Precool perishable products to the optimum temperature before and during airport handling and storage.
• Most South African airports lack adequate storage for all product temperature requirements and cross-tainting separations.
• Use compromise temperatures when optimum storage is unavailable (see Chapter 8, Table 7).
• Hold cooled product at optimum temperature in the airport cold store as long as possible before transfer to the aircraft.
• Aim to reduce transfer time from cold store to aircraft to less than one hour.
• Special aircraft containers should be loaded at optimum temperature and kept in cold store until transfer to the aircraft hold.

6. Transshipments

• Transshipment from national to international air carriers is common.
• Provide temperature protection during airport transit, even for short periods.
• If the time between arrival of a local aircraft and departure of an international aircraft exceeds three hours, hold commodities at 10°C in the airport cold store.
• Open freight containers to facilitate cooling when necessary.

7. Delays

• Perishable fruit and vegetables delayed more than three hours at airports should be held at 10°C.
• If the period exceeds three hours, highly perishable products should be held at the optimum temperatures (see Chapter 8, Table 7).
• Delays over 48 hours require re-inspection before export.
• For transshipments, the exporter or forwarding agent must inform PPECB of delays for re-inspection.
• The owner of the produce must be notified of all such delays.

8. Temperature Control During the Flight

• Temperature-controlled holds are available only on some international flights (typically -1°C to +3°C).
• Dry ice may be used for frozen produce.
• Temperature-controlled air freight containers are available on certain routes, using dry ice and air circulation fans.
• These systems can only maintain, not lower, product temperature.
• Best practices to maintain optimum temperature during flight:
  • Ensure efficient precooling to the optimum temperature.
  • Use refrigerated road transport.
  • Keep product at the correct temperature in the airport cold store.
  • Minimize time delays and exposure to warm ambient conditions during transfer.
  • Use temperature-controlled air transport equipment.

Properly precooled and handled produce has a good chance of arriving at market within acceptable temperature ranges to ensure quality.

9. After the Flight

• Move produce immediately and directly to the market.
• If storage is required, recool and cold store at the optimum temperature for the product.
• Immediately follow up on any quality problems or potential issues.
• Procedures for sea freight cargo (see Chapter 10) also apply to airfreight cargo.