Do you ever wonder why bananas will ripen when placed on the counter, but strawberries will not? The reason for this is that there are two different types of fruit: climacteric fruit and non-climacteric fruit.
What is the Difference Between Climacteric and Non-Climacteric Fruit?
Climacteric fruit will continue to ripen after harvest, while non-climacteric fruit will not continue to ripen after harvest. This is determined by the ethylene production of the fruit after harvest. By knowing which is which between climacteric vs. non-climacteric fruit, you can use that as a guide to help you when selecting produce at the grocery store and with your at-home ripening process. By learning and paying attention to this detail, you can save yourself loads of time, money and wasted produce!
A List of Climacteric vs. Non-Climacteric Fruit
| Climacteric Fruit | Non-Climacteric Fruit |
|---|---|
| Apple | Blackberry |
| Apricot | Citrus |
| Avocado | Cherry |
| Banana | Cranberry |
| Fig | Cucumber |
| Kiwifruit | Eggplant |
| Mango | Grape |
| Nectarine | Olive |
| Papaya | Pepper |
| Peach | Pineapple |
| Pear | Pomegranate |
| Persimmon | Raspberry |
| Plum | Strawberry |
| Tomato | Summer Squash |
Make sure to pay attention to the list because there are a lot of misconceptions out there regarding which fruit continues ripening. Some examples that come to mind are strawberries and pineapples, and neither of those continue ripening after harvest.
You can use the table above as a guide to help you select fruit at the grocery store. If the fruit is climacteric, you can buy it while it is not completely ripe. (If you need help figuring out how to select and store produce, you can download my free tables that teach you how to select and store 35 of the most common produce items HERE.)
Ripening Process of Climacteric Fruit
There are a few main factors that come in to play with the ripening process of climacteric fruit:
- Whether or not a climacteric fruit can ripen to its full extent is dependent on if the fruit was harvested at the proper maturity stage. An example we can all relate to is with tomatoes. Tomatoes are climacteric fruit that continue ripening after harvest. However, they need to reach a certain maturity stage while still on the plant in order to ripen properly after harvest. If not and they are harvested prematurely, it results in the issues we see with store-bought tomatoes that cannot compare to home grown tomatoes. You can read more on that topic here.
- As climacteric fruit ripens, it naturally produces ethylene gas. When the fruit is exposed to more ethylene gas, it acts as a natural catalyst to further the ripening process. For example, have you ever heard of the “trick” of putting a banana and an apple in a paper bag together to ripen the banana? People do this because the apple is already in the ripening process, and is giving off ethylene gas. This ethylene gas acts as a catalyst for the ripening process of the banana. This same concept can be applied to other climacteric fruit stored together in a bag or on the counter. For example, if you put ripe bananas in a bag with a hard avocado, the ethylene gas given off by the bananas will help speed up the avocado ripening process. It should also be noted that if you place the climacteric fruit next to each other on the counter, they will also help each other to ripen faster.
- If climacteric fruit is kept at a lower temperature, ethylene will not have as much of an impact. This is why avocados from the store will only ripen when placed on the counter versus the fridge.
What Happens to Non-Climacteric Fruit?
After harvest, non-climacteric fruit does not continue ripening. However, it does continue breathing and respiring. This ultimately leads to fruit aging, but does not result in any further ripening of the fruit. Non-climacteric fruit does not continue ripening after being harvested.
There are also vegetables that are highly susceptible to ethylene production and cannot be shipped or stored in contact with climacteric fruit. For example, yellowing of broccoli and Russet spotting in heads of lettuce.
If you enjoyed this article, here are a few others you might enjoy:
- What is Ethylene & How is it Used?
- Why Don’t My Store-Bought Tomatoes Taste Good?
- Why Won’t My Avocados Ripen?
Resource
Kader, Adel A. “Postharvest Biology and Technology: An Overview.” Postharvest Technology of Horticultural Crops, 3rd Edition. Oakland, CA: University of California Agriculture and Natural Resources, 2002. 39-47. Print.
I have a plum tree with about 100 almost ripe plums. If I remove the plums to ripen off the tree should I place them in the refrigerator or on my counter?
Hello, thanks for the comment! If you are going to pick them prior to them becoming fully ripe, then you can place them on the counter to ripen and once they reach the desired softness, you can put them in the fridge so that they will keep for longer. However, if you plan on harvesting them all at one time, you might want to look into freezing some of them, making your own jam or giving some away to make sure none of your fruit goes to waste.
What about oranges? If I leave them on the counter with a basket containing apples they seem to get moldy quickly.
This post comes close to exposing one of the dirty little secrets of industrial agribusiness: they want you to buy fruit that looks ripe on the outside but will never actually ripen. Why? Because, under reduced-oxygen cold storage, fruit that was harvested before physio-maturity can have its shelf life extended by a factor of several months over fruit that was honestly harvest-ready when picked.
The classic example is that horrible cultivar of “Red Delicious” apple that colors up to a deep red while still green inside. The combination of bitter red skin and green, sour flesh makes for a truly disgusting eating experience.
It’s a problem that’s also seen with pears that never soften. You figure that you might as well cut it open — it’s been a week since you bought it — and it’s riddled with streaks of brown rot even though it’s still hard. But it’s too late: you’ve already been duped.
This is why we should all have our own backyard fruit trees.