Please note that avocados produce more heat than bananas! Cooling may be slower than is needed when using banana rooms to ripen avocados.
Early season avocados may take longer to ripen than middle to late season ones.
- Mature green avocados should be shipped at 5 to 10.5°C, pulp temperature. Before ripening begins, the fruit pulp temperature should be raised to 18-20°C.
- If not using pressurized ripening rooms, air stack the boxes (at least 2″ between boxes) to have proper air circulation. Leave 0,5 m feet between walls and pallets and at least 15 cm between pallets.
- Once the fruit pulp temperatures stabilize, place a Catalytic Generator in the room, fill it with Ethy-Gen® II Concentrate. Apply 100 ppm ethylene; exposure time is dependent upon season of harvest, age of fruit, and maturity level at harvest. Use the recommendations below as a guide, and make sure to check avocado firmness* to know when to stop ethylene application:
- Early season fruit: 36-48+ hours
- Mid-season fruit: 24-36 hours
- Late season fruit: 12-24 hours.
To achieve 100 ppm, the generator setting will depend on the size of the ripening room.
- #1: 1 Litre every 48 hours; 43 – 70 m3
#2: 1 Litre every 36 hours; 71 – 141 m3
#3: 1 Litre every 24 hours; 142 – 212 m3
#4: 1 Litre every 12 hours; 213 – 340+ m3
Please note that all rooms vary in terms of how air-tight they are, so if more precise PPM determination is required, air testing for ethylene PPM levels is recommended.
DO NOT use any of our generators in rooms of less than 43 m3
*Here’s where to find avocado firmness testers: QA Supplies.
- Humidity is very important. It should be maintained at 90-95%.
- Carbon dioxide will build up during ripening. Anything above 1% may retard ripening or cause “checkerboard” ripening within the room. If automatic ventilation is not in place, be sure to vent approximately every 12 hours by opening the doors for 20 minutes even while applying ethylene.
- Check pulp temperature at least twice per day and maintain proper pulp temperature.
- The fruit should be ready to ship within 3-6 days depending on the season, pulp temperature and degree of firmness. Ripened fruit may have the stem end button become more pliable indicating the softness process is beginning.
- Once ripening has reached the desired degree of firmness, lower the pulp temperature to 4.5 to 5.5°C.
CAUTION: Do not hold mature green, unripened avocados at pulp temperature below 4.5°C. Chilling injury will occur, and the longer avocados are held at low temperatures, the more severe the injury that will be caused. Chilling causes grayish-brown discoloration of the skin and flesh. If chilled before ripening, the fruit will not ripen properly.Ripened avocados are less susceptible to chill damage; they can be stored as low as 2°C.
For more information on avocados and other fruits, please visit the web site of UC Davis. A great resource for any Fruit Ripener is a publication from UC Davis entitled “Fruit Ripening & Ethylene Management.”
These recommendations were amassed from a diverse number of sources for use by clients of Catalytic Generators Australia. While we have made great effort to provide accurate and current ripening techniques, Catalytic Generators makes no warranties regarding these recommendations or the applicability of such information to a particular ripening operation. Please note that we do not provide these recommendations as a replacement for technical ripening experts; if having ripening problems or starting a ripening program, we suggest that professionals be consulted.