Finding the perfectly ripe fruit is hard. We all know the drill: you buy some soft-ish peaches from the market and the next day they are moldy. You buy a cantaloupe and can’t tell if it is ready to eat until you cut into it. And who could forget the ever elusive avocado? Although it may not seem like it, ripening is, in fact, a science. Come with us as we dig into the wild world of climacteric fruit!
What makes a fruit or vegetable climacteric?
It is generally understood that there are two types of produce: climacteric and non-climacteric.
The difference between a climacteric piece of produce and a non-climacteric comes down to ethylene. Climacteric fruit have an intense reaction to ethylene (which is a ripening hormone that produce creates in order to ripen [Washington State University]), meaning that when a climacteric fruit or vegetable comes into contact with ethylene, it responds by creating more ethylene and begins to respire at a high rate, which further promotes its ripening process. Therefore, these pieces of produce will ripen after they are picked.
Non-climacteric fruit or vegetables, on the other hand, do not show a heightened production of ethylene and CO2 when coming in contact with ethylene, and most non-climacteric fruits and vegetables will simply continue living their lives. However, there are some non-climacteric fruits and vegetables that actually have a negative response to ethylene, such as browning in lettuce. In order for your fruits and vegetables to live a long and happy life, an easy way is to make sure these types of produce stay away from each other:
Information from Concord Co-Op
Time for a plant science lesson
So, most fruits and vegetables produce ethylene. But what exactly happens to the fruit during these periods of production?
For climacteric produce, they’re picked when they are full of starch. Once they’re picked and are met with enough ethylene, this triggers physiological responses like color change and the breakdown of polysaccharides (i.e. starch) into monosaccharides, making the fruit or vegetable sweeter and easier for human consumption.
Since fruits and vegetables have evolved for consumption by other organisms in order to spread their seeds throughout the earth, the color change and break down of sugars occurs to tell herbivores that it is ready for its seeds to be fertilized. Therefore, this process is essential for fruits and vegetables to diversify their gene pool and continue to grow.
Examples of climacteric and non-climacteric fruits
Using science to work for you
For eons, animals and humans have solely relied on the produces’ natural production of ethylene to ripen fruits. However, as technology has gotten better and we have learned more about fruits and vegetables, there are some home remedies that you can use in your home to either increase or decrease the rate of your produces’ ripening process.
Take our favorite fruit for example: avocados.
If you have an unripe avocado, put it in an enclosed space (a paper bag will do the trick) with other avocados. This way, you’ll trap in the ethylene that is being produced which will trigger the climacteric response and will make your avocados ripen more quickly.
In order to slow down the ripening process, put your avocados in the fridge, as the cold air will slow down the ethylene production. However, do not put them in the freezer, as this could stop the process completely.
If you’re a grower, we have an even simpler solution: using Apeel on your avocados in order to make them last longer. This will allow you to unlock new market opportunities (i.e. exporting internationally in addition to selling locally) and to deliver high-quality products to your customers, driving preference for your fruits!
Want to learn more?
Special thanks to Alex Thomas, Ph.D., Amy Keech, and Cody Vild, Ph.D.