Tips To Help You Manage Postharvest Ripening

Elizabeth MitchamDuring the ripening process, fruit develops desirable eating qualities, including enhanced sweetness, soft and juicy texture, and unique flavor characteristics.

These ripe characteristics make the fruit more desirable to seed dispersers of all types, including animals, birds, and humans. Some fruit must ripen fully on the plant to develop optimum flavor quality. This includes strawberries, sweet cherries, melons, raspberries, oranges, and peaches, to name a few.

Other fruit are harvested mature and ripened after harvest. The term mature means that the fruit have attained a stage at which they can be harvested and ripened to good quality after harvest.

Most of these fruit contain starch reserves at the time of harvest that are converted to sugars after harvest, and therefore the quality of the fruit improves after harvest. This category includes apples, European pears, bananas, kiwifruits, and mangoes.

Getting Fruit Ready To Eat In The Market
Today’s consumer prefers to purchase fruit that are ready to eat. To satisfy this demand, many fruit are ripened partially before retail display. Bananas are the fruit most commonly ripened for retail display, and many years of research and commercial practice has led to the specific protocols that are used by banana ripeners today. Tomatoes (those harvested mature green) and avocados are also frequently ripened after harvest, and pear, kiwifruit, and mango ripening is becoming increasingly common.

There are a number of important factors to consider when ripening fruit to achieve uniform, high-quality ripened products. The most important is the temperature of the product.

Warmer temperatures lead to faster rates of ripening and cooler temperatures slow ripening. However, if the temperature is too high it can impair the flavor quality of the fruit or inhibit full ripening in some cases.

Ripening is best achieved at temperatures between 55°F and 77°F; however, bananas are ripened at lower temperatures (58°F to 65°F). To achieve uniform temperatures within the ripening fruit and therefore ripeness uniformity among the fruit, effective airflow through the packages is required. This is important to bring the fruit to ripening temperatures, manage the temperature during ripening, and, in some cases, cool the fruit after ripening to slow further ripening.

Use of a forced-air system (sometimes called pressure ripening) designed to force room air through the boxes is preferred. Adequate ventilation of the packaging material is critical for airflow. Use of liners and bags will inhibit airflow. When forced-air systems are not available for ripening, boxes can be stagger-stacked on pallets to enhance air exchange for temperature management.

Use Of Ethylene Gas
In addition to uniform temperatures, the ripening of some fruit, such as bananas and green tomatoes, requires the addition of ethylene gas. For other fruit, ripening is faster or more uniform if ethylene gas is added during the ripening process.

Ethylene can be applied using compressed gas cylinders containing diluted ethylene gas or with specialized ethylene generators that release a preset amount of ethylene continually. Ethylene concentrations of 100 parts per million are more than sufficient to stimulate ripening.

Care should be taken to avoid accumulating excessive concentrations of ethylene. When ripening rooms are vented, avoid contamination of produce storage areas, as ethylene has negative impacts on green vegetables and some fruit.

Monitor For Carbon Dioxide
Another gas that must be monitored during fruit ripening is carbon dioxide. If carbon dioxide concentrations are allowed to accumulate higher than 0.5%, this can slow the rate of ripening.

To avoid carbon dioxide accumulation, ripening rooms should, at minimum, be ventilated once every 24 hours. Products with high respiration rates, like bananas and avocados, require about two air exchanges per hour in a typical ripening room filled with fruit. This should be done even while ethylene is being applied, being careful to vent the ethylene to the outside and not the warehouse.

Finally, care should be taken to maintain high relative humidity in the ripening room. At warm ripening temperatures, the rate of water loss from the fruit can be very high if 85% to 95% relative humidity is not maintained.

For more information about ripening of fruit, refer to the Fruit Ripening & Retail Handling Manual produced by the Postharvest Technology Center at Postharvest.UCDavis.edu/bookstore.

Topics: , ,

Leave a Reply

Fruits Stories
honeybees
Citrus
March 25, 2017
New Videos Offer Tips on Planting Pollinator Habitats
A new video series on planting flowering habitats is designed to help growers support crop pollinators. Read More
Freeze protected blueberry bushes in Florida
Berries
March 25, 2017
Florida Blueberry Crop Escapes Slap from Late-Season Cold Snap
Freeze protection tactics prove fruitful as local producers look to gain from Georgia’s loss. Read More
Apples & Pears
March 25, 2017
Two MAIA Releases Available for Growers, Hobbyists
‘Crunch-A-Bunch’ is an early ‘GoldRush’ and ‘Bakers Delight’ is a secret ingredient for baking. Read More
Citrus
March 24, 2017
Marrone Bio Introduces Biostimulant to Reduce Sun Stress
Haven Anti-transpirant helps to reduce transpiration of fruit, nut, and vegetable crops. Read More
Campus of Massey University in New Zealand
Citrus
March 23, 2017
Count Down the World’s Top 30 Agriculture Colleges
Familiar names and several new faces among annual ranking’s elite. Read More
Business Planning
March 22, 2017
How HortTech Is Solving Grower Challenges
Dozens of tech companies are looking for solutions to real-world problems vegetable growers face. We take a look at what it could really mean for you and your business. Read More
Citrus
March 21, 2017
Industry Groups, Ag Leaders React to Proposed USDA, EPA Budget Cuts
New plan would slash USDA spending by 21%. Read More
Freeze protected peach trees in Florida
Cold Protection
March 21, 2017
Freezing Temperatures Hit South Carolina Crops Hard
Peaches, blueberries, and strawberries among crops damaged. Read More
fork digging into a plate full of salad
Citrus
March 21, 2017
Since When Did Eating Get So Complicated? [Opinion]
The bottom line to all this is the way we eat is undergoing massive disruption. Read More
Apples & Pears
March 21, 2017
Two More Lost Apple Varieties Found In Steptoe Butte
Amateur apple detective strikes again with two more finds in abandoned orchards near state park. Read More
Organic potato grower staring at his crops
Crop Protection
March 20, 2017
Biologicals Gaining Acceptance Among More Growers
Driven by new innovation and consumer demand, growers look to the biocontrol sector for new solutions. Read More
Swadesh Santra of UCF
Citrus
March 16, 2017
UCF Stepping up to Be Farming’s Knight in Shining Armor
Hopes are high that the school's new agriculture research center will help growers solve production issues and feed the globe. Read More
Frozen blueberries
Berries
March 15, 2017
Arctic Blast Gives Southern Fruit Growers the Chills
Peaches and berries in bloom most at risk from freezing temperatures. Read More
Citrus
March 15, 2017
Group Wants To Streamline Food Safety Regulations
There are 15 federal agencies implement more than 30 different food safety statutes. A team of experts believe they have a solution. Read More
UFGem peach variety
Marketing
March 15, 2017
Florida Peaches Scoring Points with Consumers on the Go
Snack-sized fruit presents unique marketing opportunity for growers. Read More
The Latest
Citrus
March 25, 2017
New Videos Offer Tips on Planting Pollin…
A new video series on planting flowering habitats is designed to help growers support crop pollinators. Read More
Citrus
March 24, 2017
Marrone Bio Introduces Biostimulant to R…
Haven Anti-transpirant helps to reduce transpiration of fruit, nut, and vegetable crops. Read More
Citrus
March 23, 2017
Count Down the World’s Top 30 Agricultur…
Familiar names and several new faces among annual ranking’s elite. Read More
Business Planning
March 22, 2017
How HortTech Is Solving Grower Challenge…
Dozens of tech companies are looking for solutions to real-world problems vegetable growers face. We take a look at what it could really mean for you and your business. Read More
Citrus
March 21, 2017
Industry Groups, Ag Leaders React to Pro…
New plan would slash USDA spending by 21%. Read More
Cold Protection
March 21, 2017
Freezing Temperatures Hit South Carolina…
Peaches, blueberries, and strawberries among crops damaged. Read More
Citrus
March 21, 2017
Since When Did Eating Get So Complicated…
The bottom line to all this is the way we eat is undergoing massive disruption. Read More
Crop Protection
March 20, 2017
Biologicals Gaining Acceptance Among Mor…
Driven by new innovation and consumer demand, growers look to the biocontrol sector for new solutions. Read More
Citrus
March 16, 2017
UCF Stepping up to Be Farming’s Kn…
Hopes are high that the school's new agriculture research center will help growers solve production issues and feed the globe. Read More
Berries
March 15, 2017
Arctic Blast Gives Southern Fruit Grower…
Peaches and berries in bloom most at risk from freezing temperatures. Read More
Citrus
March 15, 2017
Group Wants To Streamline Food Safety Re…
There are 15 federal agencies implement more than 30 different food safety statutes. A team of experts believe they have a solution. Read More
Citrus
March 14, 2017
Can Your Farm Survive If the Grid Goes D…
Even in a plugged-in world, the basics are needed now more than ever. Read More
Citrus
March 14, 2017
Concerns Mount in the Sunshine State Ove…
Water conservation efforts called for as the dry season rolls on. Read More
Fruits
March 14, 2017
Some Fruit Bud Damage Seen In Northeast;…
Researchers say fluctuating temperatures have confused trees, but perhaps any damage occurred will help thin out crops. Read More
Food Safety
March 10, 2017
Strawberries, Spinach Top Latest ‘…
Industry groups dispute annual report, noting any report that has the effect of decreasing Americans’ fruit and vegetable intake is injurious to their health. Read More
Citrus
March 7, 2017
The Andersons Divests Florida Farm Cente…
Local, family owned custom blend fertilizer company taking over assets and product distribution responsibilities. Read More
Citrus
March 6, 2017
More Growers Willing to Bet on Biocontro…
Industry event highlighting alternative pest management methods draws interested crowd to Reno. Read More
Farm Management
March 2, 2017
Growing Demand for High Tech Agriculture…
Ideas welcome at event geared for innovators. Read More