Ethylene Production:
Very low at 0 °C, low at 20 °C for unripe kiwis, high at 20 °C for ripe kiwis
Controlled Atmosphere:
Recommended
Temperature: Store at –0.5 °C to 0 °C.
High Humidity: Install humidifiers set to the upper limit of desired RH, or use forced-air cooling systems with minimal ΔT differential.
Storage Duration: Recommended period is 4 to 7 months.
Ventilation: Conduct a detailed study and install a digitally-controlled CO₂ extraction system from the chamber.
Air Recirculation: Install inverter-driven fans with full 24-h coverage of the chamber air-mass.
Ozone: Use ozone generators to combat microbial load.
Ethylene Removal: Recommend using ethylene burners or absorption systems.
Controlled Atmosphere: For long-term storage, target ~1.5–2% O₂ and ~3–4% CO₂. This CA can extend storage up to 210 days, maintaining firmness of the fruit flesh.
Dynamic Pre-Cooling: A tailored study of cooling-time and air-velocity ensures uniform cooling down to the core of the product.
Dynamic Cooling: Multi-point monitoring and control of storage parameters across the entire chamber, with 24-h coverage.
IMPORTANT TIPS
Rapid pre-cooling to 2-4 °C is essential: maintain the cold chain in all distribution stages.
For kiwis where the peduncle wound has not healed, hold them out of pre-cooling for 24 h below 20 °C.
Maintain uniform sub-zero temperatures within storage chambers; leave voids between pallets.
Dynamic Cooling is highly recommended.
Remove all ethylene exposure—kiwis are extremely sensitive to trace ethylene.
Maintain CO₂ at moderate levels (which delays ripening) but not above ~10% (which may cause core hardening).
For long term storage: harvest kiwis with flesh firmness > 8 kg force and soluble solids > 6.2 °Bx.
Sanitize cold-rooms before use.
Use ozone in off-phase with ethylene burners to reduce microbial load.
