General Principles
- Cultivar differences must be recognised.
- Some apple cultivars develop internal disorders if stored below 0.0°C for long periods.
- Early fruit with low sugars is prone to freezing.
- Too fast cooling of some cultivars (e.g., Granny Smith) may lead to core flush.
- CO₂ generation is low at 0.0°C or lower but increases rapidly at higher temperatures (1.0 to 5.0°C).
- Plastic bags are used to retain green colour.
- Fruit in plastic bags cools slower than those without plastic bags.
- When pallets with different packaging are loaded into a container, pallets with poorer ventilation packs (e.g., plastic bags) must be loaded first, as cooling at the door-end is not as good as near the refrigeration unit.
- Fruit in unperforated plastic bags must be loaded out within set tolerances to avoid possible warming inside containers.
- Some markets demand plastic bags (Far East/Africa).
- If fruit is in plastic bags, container vents can be closed (energy saving).
- For fruit shipped below 0.0°C, it is recommended that the vents be closed.
- Fruit treated with 1MCP may be stored at +1.0°C or higher compared to non-treated fruit.
- Relative Humidity should be kept between 90 and 95%.
Regulatory information is available on PPECB’s website (www.ppecb.com) – see Documents: Normal Shipments – HP28 Handling Procedure and Optimum Temperatures for Sea Exports of Pome Fruit.
Cooling Guidelines for Apples
A. Standard Protocols
| Risk Level | Cultivar | Type/Comments | Plastic Bags | Load Out Temp | Set Point | Code | Vents |
|---|---|---|---|---|---|---|---|
| High Risk (HR) | Panorama Golden D | Early season, week 12 | Yes | 0.0°C–+3.0°C | 0.0°C | D0 | Closed if in sealed bags |
| Golden Delicious | Early season, week 12 | Yes | 0.0°C–+3.0°C | 0.0°C | D0 | Closed if in sealed bags | |
| Granny Smith | Louterwater GS, Brix <11°Brix | Optional | 0.0°C–+3.0°C | 0.0°C | D0 | Closed if in sealed bags | |
| Fuji | IB prone areas (Internal Browning) | ||||||
| Joya | As per protocol | ||||||
| Envy | As per protocol, do not cool <0°C | Perforated | 0.0°C–+3.0°C | 0.0°C | D0/D0.5 | Open | |
| Cripp’s Red | |||||||
| Cripp’s Pink | Late picked | ||||||
| Pink Lady | |||||||
| Fuji (B) | As per season’s requirements | Optional | -0.5°C–+3.0°C | -0.5°C | D-0.5 | Closed if in sealed bags | |
| Gala | |||||||
| Moderate Risk | Starking/Topred Mutants | Optional | Optional | -0.5°C–+3.0°C | -0.5°C | D-0.5 | Closed if in sealed bags |
| (MR) | Braeburn | ||||||
| Panorama Golden D (MR) | Optimum maturity, only first week | No | -0.5°C–+3.0°C | -0.5°C | D-0.5 | Open | |
| Golden Delicious (MR) | Optimum maturity, only first week | No | -0.5°C–+3.0°C | -0.5°C | D-0.5 | Open | |
| Granny Smith (MR) | Optimum maturity, only first week | No | -0.5°C–+3.0°C | -0.5°C | D-0.5 | Open | |
| Low Risk | All treated with 1MCP | Handle at >0°C to save energy | Optional | -0.5°C–+3.0°C | -0.5°C | D-0.5 | Closed if sealed bags |
Notes:
- Risk Level refers to disorders and damage caused by too low temperatures (freezing, cold damage, internal browning, scald).
- These are guidelines; specific circumstances, markets, and maturity may require deviations.
- Early variants of main cultivars (e.g., Panorama Golden Delicious, Louterwater Granny Smith, and not fully matured Golden Delicious/Granny Smith) are high risk and must follow protocols. Low sugar levels often lead to cold damage.
Cooling Guidelines for Pears
| Risk Level | Cultivar | Type/Comments | Plastic Bags | Load Out Temp | Set Point | Code | Vents |
|---|---|---|---|---|---|---|---|
| High Risk (HR) | Early Bon Chretien | High respiration fruit, 37.5µm bag | Closed if unperforated | ||||
| Bon Chretien | Cold chain must be maintained | Closed if DAT <0°C | |||||
| Bon Rouge & Victoria Blush | |||||||
| Rosemarie & Sempre (Summer) | DP1 | ||||||
| Flamingo & Sempre | -0.5°C–+1.5°C | ||||||
| Beurre Hardy | |||||||
| Doyenne du Comice | |||||||
| Cheeky & Cape Rose | |||||||
| Celina & Qutee | |||||||
| Packhams Triumph (HR) | DCA Stored (Dynamic Controlled Atmosphere), sometimes act as WBC | Yes | -1.0°C | ||||
| Moderate Risk | Early Season Packhams Triumph | Possible CO₂ damage at ≥2°C, low sugar levels are freezing prone | 0.0°C–+2.0°C | 0.0°C | D0 | Closed if in sealed bags | |
| (MR) | Abate Fetel | ||||||
| Low Risk (LR) | Packham’s Triumph (LR) | Treat with 1MCP if pressures <6kg, preferably without plastic bags (beware shrivelling) | With bags: +3.0°C, -1.0°C; Without bags: +4.0°C, -0.5°C | DP1/D-0.5 | Optional, keep CO₂ risk in mind | ||
| Forelle & Vermont Beauty | Special protocols to be followed | 0.0°C–+2.0°C | 0.0°C | D0 | Closed if in sealed bags | ||
| FEMA Forelle & Vermont Beauty | Winter pears | -0.5°C–+2.0°C | -0.5°C | D-0.5 | Optional, keep CO₂ risk in mind | ||
| Beurre Bosc, Golden Russet Bosc |
Note: The choice of plastic bag (microns) is important. Lower microns (e.g., 20) are more permeable and reduce the risk of CO₂ damage.
Loadshedding Contingency Protocols (Phase 4 and Higher)
Apples
| Risk Level | Cultivar | Comments/Type | Plastic Bags | Load Out Temp | Set Point | Code | Vents |
|---|---|---|---|---|---|---|---|
| High Risk (HR) | Panorama Golden D | Early season, week 12 | Yes | 0.0°C–+5.0°C | 0.0°C | D0 | Closed if in sealed bags |
| Golden Delicious | Early season, week 12 | Yes | 0.0°C–+5.0°C | 0.0°C | D0 | Closed if in sealed bags | |
| Granny Smith | Louterwater GS, Brix <11°Brix | Optional | 0.0°C–+5.0°C | 0.0°C | D0 | Closed if in sealed bags | |
| Fuji | IB prone areas | ||||||
| Joya | As per protocol | ||||||
| Envy | As per protocol, do not cool <0°C | Perforated | 0.0°C–+5.0°C | 0.0°C | D0/D0.5 | Open | |
| Cripp’s Red | |||||||
| Cripp’s Pink | Late picked | ||||||
| Pink Lady | |||||||
| Fuji (B) | As per season’s requirements | Optional | -0.5°C–+5.0°C | -0.5°C | D-0.5 | Closed if in sealed bags | |
| Gala | |||||||
| Moderate Risk | Starking/Topred Mutants | Optional | Optional | -0.5°C–+5.0°C | -0.5°C | D-0.5 | Closed if in sealed bags |
| (MR) | Braeburn | ||||||
| Panorama Golden D (MR) | Optimum maturity, only first week | No | 0.0°C–+5.0°C | 0.0°C | D0.5 | Open | |
| Golden Delicious (MR) | Optimum maturity, only first week | No | 0.0°C–+5.0°C | 0.0°C | D0.5 | Open | |
| Granny Smith (MR) | Optimum maturity, only first week | No | 0.0°C–+5.0°C | 0.0°C | D0.5 | Open | |
| Low Risk | All treated with 1MCP | Handle at >0°C to save energy | With bags: 0.0°C–+5.0°C; Without bags: -0.5°C–+5.0°C | With bags: 0.5°C; Without bags: -1.0°C | D0.5/D-1.0 | Optional/Closed if sealed bags |
Notes:
- Risk Level refers to disorders and damage caused by too low temperatures (freezing, cold damage, internal browning, scald).
- These are guidelines; specific circumstances, markets, and maturity may require deviations.
- Early variants of main cultivars (e.g., Panorama Golden Delicious, Louterwater Granny Smith, and not fully matured Golden Delicious/Granny Smith) are high risk and must follow protocols. Low sugar levels often lead to cold damage.
Pears
| Risk Level | Cultivar | Comments/Type | Plastic Bags | Load Out Temp | Set Point | Code | Vents |
|---|---|---|---|---|---|---|---|
| High Risk (HR) | Early Bon Chretien | High respiration fruit | -1.0°C | ||||
| Bon Chretien | Cold chain must be maintained, no plastic bags | Optional (beware CO₂ damage) | |||||
| Bon Rouge & Victoria Blush | |||||||
| Rosemarie & Sempre (Summer) | DP1 | ||||||
| Flamingo & Sempre | Treat with 1MCP possible (riper fruit) | -0.5°C–+1.5°C | D-0.5 | ||||
| Beurre Hardy | |||||||
| Doyenne du Comice | |||||||
| Cheeky & Cape Rose | |||||||
| Celina & Qutee | |||||||
| Packhams Triumph (HR) | DCA Stored (Dynamic Controlled Atmosphere), sometimes act as WBC | Yes | -1.0°C | DP1 | |||
| Moderate Risk | Early Season Packhams Triumph | Possible CO₂ damage at ≥2°C, low sugar levels are freezing prone | 0.0°C–+2.0°C | 0.0°C | D0 | Closed if in sealed bags | |
| (MR) | Abate Fetel | ||||||
| Low Risk (LR) | Packham’s Triumph (LR) | Treat with 1MCP if pressures <6kg, preferably without plastic bags (beware shrivelling) | With bags: +3.0°C, -1.0°C; Without bags: +4.0°C, -0.5°C | DP1/D-0.5 | Optional, keep CO₂ risk in mind | ||
| Forelle & Vermont Beauty | Special protocols to be followed | 0.0°C–+2.0°C | 0.0°C | D0 | Closed if in sealed bags | ||
| FEMA Forelle & Vermont Beauty | Winter pears | -0.5°C–+2.0°C | -0.5°C | D-0.5 | Optional, keep CO₂ risk in mind | ||
| Beurre Bosc, Golden Russet Bosc |
Note: The choice of plastic bag (microns) is important. Lower microns (e.g., 20) are more permeable and reduce the risk of CO₂ damage.