When ripening avocados, it’s important to remember that middle- and later-season avocados undergo a faster ripening time than early avocados.
Avocado ripening tips
Some factors to keep in mind when ripening avocados include:
– Humidity: Maintain a humidity level between 90% and 95%.
– Carbon dioxide: A carbon dioxide level over 1% may slow the ripening process. If you do not have automatic ventilation, be sure to ventilate the room by opening the door for 20 minutes every 12 hours while applying ethylene.
– Pulp temperature: Check the temperature of the pulp at least twice per day. Once you reach the desired degree of firmness, lower the pulp temperature to 40-42°F (4.5 to 5.5°C).
Apply 100 ppm ethylene; exposure time depends upon harvest season, 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. 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.
Caution: Do not hold mature green, unripe avocados at pulp temperature below 40°F / 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 36°F (2°C).