Critical success factors in transporting mango fruit - Presentation from the Darwin Mango Field Day

1. Critical success factors in
transporting mango fruit
Peter Hofman, Scott Ledger

2. Critical considerations
Quality attributes at risk
• Over-ripe / under-ripe fruit
• Variable ripening between and within pallets
• Poor skin colour
• Chilling damage
• Skin marks
Key issues
• Temperature of fruit at loading
• Pallet configuration in the container
• Refrigeration capacity/air circulation/insulation
• Gas accumulation (mainly carbon dioxide)

3. Quality risks; too ripe, uneven ripe, chilling
• Pre-cooling room temperature too high (>12ºC)
• Pre-cooling time too short
• Forced-air cooler not used or loaded incorrectly
• Cool room not functioning properly
High fruit temperatures at loading

4. Loading warm fruit causes uneven ripening
Truck temperature 13ºC Average fruit temperature at loading 21ºC

5. Loading warm fruit causes chilling injury
Delivery air 6ºC
below set point
Set point 13ºC

6. Chilling injury
Poor pre-cooling and container loading/performance
Temperature setting too low - <10°C
•Poor container loading
•Poor container insulation (tautliners)
•Fruit exposed on top of pallets near delivery air
•Faulty equipment operation

7. Set temperature 18°C; fruit temperature at loading 19°C
Xsense tag 3 pallet layers down, 2nd row from front
Date and time
24/11 25/11 26/11 27/11 28/11 29/11
Temperature(
o
C)
15
20
25
30
35
40
2nd row from front (Xsense)
2nd row from backLoaded
Unloaded
Poor cooling performance

8. Quality risk; too ripe, uneven ripe
• Fruit temperature too high at loading
• Faulty refrigeration
• Poor insulation, e.g. tautliners
• Poor pallet loading
• Air flow obstructed
Poor cooling performance

9. Good, even airflow is critical
✓
From Ledger 2012

10. Good, even airflow is critical
Under these conditions, the fruit on the outside of the pallet cooling
down significantly more quickly than those in the middle.
Temperature probe ring only the fruit on the outside of the pallet will
often give a false indication
Refrigeration
unit
Roof shoot
Ply sheet restricting
both cold air delivery to
front pallets, and return
of warm air to return
vent
Cold delivery air
vent
Warmer return air
vent
Warmer return air
through pallet
boards and/or floor
vents
Restricted
cold air to
front pallets
Cold air short-
circuiting directly
to the return
vent
Pallets

11. Transport do’s and don’ts
 Pallet placed tight against
bulkhead
✓
 Gap left between bulkhead and 1st
row of pallets – air short circuits

12. Transport do’s and don’ts
 Stabilizing boards crossed to avoid
blocking air flow under pallets
✓
 Stabilizing boards and pads
block air flow under pallets

13. • Carbon dioxide and other volatiles
• High fruit temperatures causing high respiration
• Poor ventilation
Gas accumulation
Risks; Skin spotting, poor colour, off flavours, WHS

14. Date (Nov 2012)
14th 15th 16th 17th 18th 19th
Carbondioxide(%)
0
5
10
15
20
25
Loaded into
container
Removed from
container
Temperature and carbon dioxide
Fruit temp.
on arrival
24oC
17oC

15. • Loose packing and over-packing
• Hard inserts
• Incorrect stacking, pallet strapping
• Pallets not secured effectively in vehicle
• Rough roads and driving too fast
Quality risk; Transport rub, pallet collapse
Packing and roads/driving

16. Critical success factors
• Fruit temperatures before loading
– Cool to within 2oC of transport temperature
• Correct pallet configuration
– No gaps between first pallet and bulkhead, or
– Ply from top of first pallet to bulkhead
• Don’t block return air flow
– Use angled or fluted ply sheets
• Adequate refrigeration and insulation
– Don’t use tautliners on long journeys
• Tight pack, soft inserts - drive to road conditions
• Minimise carbon dioxide hazards
– Low fruit temperatures
– Venting
– Lime