Fruits & Vegetables Producing Ethylene Or Sensitive To Ethylene

We all know that one bad fruit in the box spoils the whole box of fruits. Only one apple, banana, kiwifruit, mango or guava can spoil the other fruits placed nearby. Why it is so? What causes fruits and vegetables to rot? The reason is the ethylene gas released by fruits and vegetables [1] which is a ripening gas. It should be noted that the ethylene gas is used to ripen raw fruits. You should know what fruits and vegetables emit ethylene gas, and which give off most.

Find a list of fruits and vegetables that produce ethylene gas and the foods which are sensitive to ethylene.

Ethylene Producing Fruits

Fruits Ripening Gas - Ethylene

The natural question is what is ethylene gas, how it is used and is it safe for humans. Ethylene is a hydrocarbon gas (C₂H₄, molecular weight 28.05), flammable, odorless, harmless and tasteless [2]. It is a type of plant hormone, known as senescence hormone released by fruits and vegetables. In the plant, it is produced by the aging tissues and nodes of stems. It is obtained from petroleum and natural gas.

Effect of Ethylene on Fruit Ripening?

You may be interested to know how does the presence of ethylene affect fruit ripening. The effect of ethylene (senescence hormone) is to promote ripening of fruits to make them softer and sweeter. The ethylene, therefore, is a natural ripening agent. Ethylene is a plant hormone resulting from metabolism, whose role is to ripen the fruits. It should be noted that if you do not monitor ripening carefully, your fruit may rot as the quicker ripening is actually a form of accelerated aging that will decrease the product quality and shelf life.

In some countries, growers use calcium carbide for ripening fruit. The calcium carbide produces acetylene gas when it comes in contact with moisture. The acetylene gas is also a ripening agent similar to ethylene gas.

Following are the effects of ethylene gas on the fruits and vegetables:

1. Apples lose crunchiness
2. Fresh produce and flower decay, wilt
3. Leafy vegetables and eggplants spotting
4. Yellowing of cucumbers, broccoli and Brussels sprouts
5. Rind of citrus breaks down

e can use this knowledge on ethylene to extend the life of fruits and vegetables and prevent their spoilage.

Both fruits and vegetables release ethylene gas, however, fruits produce more ethylene than vegetables do. While some fruits and vegetables are high ethylene producers, others are more sensitive to it.

Ethylene is used to control the ripening process of fruits by introducing this gas into a controlled environment. When ethylene producing foods are kept in close proximity with ethylene-sensitive foods, the gas will speed up the ripening process of the other produce.

How To Prevent Food Spoilage

So you can speed up the ripening process of an unripe fruit by putting an ethylene producing food near to it, for example, by putting an unripe avocado with an apple in a bag.

1. The action of ethylene slows down at lower temperatures, so the fruit does not respond well to externally supplied ethylene. that is why you can store your fruits in fridge to slow down their ripening process.
2. Some fruits and vegetables are sensitive to the ethylene gas, so keep such produce away from ethylene producers as they deteriorate quickly and decay prematurely in high- ethylene environment. The degree of damage depends upon the concentration of ethylene, the temperature and duration of exposure [3].
3. High ethylene producing fruits should be kept away from other fruits and vegetables. Store fruits and vegetables separately, because fruits release more ethylene gas than vegetables, which can spoil the veggies. Keep leafy vegetables and lettuce away from fruits. Therefore, store ethylene emitting produce such as apples, avocados, bananas, melons, peaches, pears, tomatoes, etc. separately from broccoli, cabbage, cauliflower, leafy greens, lettuce, etc. as these are ethylene sensitive.
4. Do not store spinach, kale or similar leafy vegetables near apples, bananas or peaches, otherwise they will turn yellow quickly and limp [4]. 
5. Keep away your ripe foods from ethylene-producing foods to last longer.
6. Storing potatoes with apples naturally inhibit sprouting in potatoes. The potato industry introduce trace amounts of ethylene into potato storage boxes to delay the sprouting process significantly [5].
7. Keep Onions & Potatoes Separated as both can release moisture that will cause each other to spoil faster. Store them separately in a dry, cool and airy place. Many people have given ethylene as the reason for storing onions and potatoes separately, but that is not true; both potatoes and onions do not produce ethylene gas, only potato is sensitive to this gas [6].
8. Remove and discard the older rotten fruits so that your other fruits and vegetables last longer with full nutritional benefits.
9. Citrus fruits do not ripen further after they are picked so they have long self-life.
10. Note that tomatoes are not artificially reddened by ethylene. The normal tomato ripening process can be accelerated by externally applied ethylene [7].

Ethylene Producing and Ethylene Sensitive Fruits & Vegetables

The following chart [6] gives a list of foods which are high emitters of ethylene and foods that are sensitive to ethylene. Looking at the list of foods, you can make an intelligent combination of produce for storing them without spoilage.

Ethylene Producing Fruits & Vegetables
Fruits & Vegetables	Ethylene  Emission	Ethylene  Sensitivity
Apples	High	Yes
Apricots	High	Yes
Avocados, ripe	High	Yes
Avocados, unripe	Low	Yes, Very
Bananas, green	Low	Yes
Bananas, ripe	Medium	No
Blackberries	Very Low	No
Blueberries	Very Low	No
Cantaloupe	Medium	Yes
Cherries	Very Low	No
Cucumbers	Very Low	Yes
Endive	No	No
Figs (growing fig tree from cuttings video)	Low	No
Grapefruit	Very Low	No
Grapes	Very Low	Yes
Guavas	Medium	Yes
Kiwi, ripe	High	Yes
Kiwi, unripe	Low	Yes, Very
Lemons	Very Low	No
Limes	Very Low	No
Lychees	Very Low	No
Mangoes	Medium	Yes
Melons, Honey Dew	Medium	Yes
Nectarines	High	No
Okra	Very Low	Yes
Oranges	Very Low	No
Papayas	Medium	Yes
Peaches	High	Yes
Pears	High	Yes
Pineapples	Very Low	No
Plums	High	Yes
Prunes	High	Yes
Quinces	High	Yes
Raspberries	Very Low	No
Strawberries	Very Low	No
Tangerines	Very Low	No
Tomatoes, green	Low	Yes
Tomatoes, ripe	Medium	No
NO Ethylene Emission, Not Sensitive
Fruits & Vegetables	Ethylene Emission	Ethylene Sensitivity
Artichoke Sweet	No	No
Cherries sweet	No	No
Chicory	No	No
Coconuts	No	No
Corn	No	No
Cranberries	No	No
Garlic	No	No
Ginger	No	No
Kohlrabi	No	No
Onions	No	No
Peppers sweet	No	No
Pomegranates	No	No
Rhubarb	No	No

Ethylene Sensitive Fruits & Vegetables
Fruits & Vegetables	Ethylene  Emission	Ethylene  Sensitivity
Asparagus	No	Yes
Avocados, ripe	High	Yes
Avocados, unripe	Low	Yes, Very
Bananas, green	Low	Yes
Basil	No	Yes
Beets	No	Yes
Bok Choy	No	Yes
Broccoli	No	Yes
Brussels Sprouts	No	Yes
Cabbage	No	Yes
Cantaloupe	Medium	Yes
Carrots	No	Yes
Cauliflower	No	Yes
Celery	No	Yes
Cucumbers	Very Low	Yes
Eggplant	No	Yes
Grapes	Very Low	Yes
Green Beans	No	Yes
Green Peas	No	Yes
Guavas	Medium	Yes
Herbs	No	Yes
Kiwi, ripe	High	Yes
Kiwi,unripe	Low	Yes, Very
Leeks	No	Yes
Lettuce	No	Yes
Mangoes	Medium	Yes
Honey Dew	Medium	Yes
Mushrooms	No	Yes
Okra	Very Low	Yes
Papayas	Medium	Yes
Parsnips	No	Yes
Peaches	High	Yes
Pears	High	Yes
Peppers,hot	No	Yes
Persimmons	No	Yes, Very
Plums	High	Yes
Prunes	High	Yes
Potatoes	No	Yes
Pumpkins	No	Yes
Quinces	High	Yes
Radishes	No	Yes
Rutabagas	No	Yes
Salad Mixes	No	Yes
Sprouts	No	Yes
Squashes, summer	No	Yes
Squashes, winter	No	Yes
Sweet Potatoes	No	Yes
Tomatoes, green	Low	Yes
Turnips	No	Yes
Watermelon	No	Yes, Very

Fruits & Vegetables That Produce Ethylene

Some fruits and vegetables emit more ethylene at a much higher rate than others. The question is which foods emit the ethylene gas most?

Apples, Apricots, ripe Avocados, Cantaloupe, Guavas, Mangoes, Nectarines, Papayas, Peaches, Pears, Plums, Prunes, Quinces and ripe Tomatoes are high to medium ethylene producing fruits; while Berries (Blackberries, Blueberries, Cherries, Raspberries, Strawberries), Cucumbers, Figs, Grapefruit, Grapes, Lemons, Limes, Lychees, Okra, Oranges, Pineapples and Tangerines produce only a small amount of ethylene gas.

The following fruits and vegetables are ethylene emitting fruits and they themselves are sensitive to it.

Apples, Apricot, Avocado (ripe &  unripe), Bananas (green), Cantaloupe, Cucumber, Fig, Grapes, Guava, Kiwi, (ripe & unripe), Mango, Honey Dew Melon, Okra, Papaya, Peach, Pear, Plum, Prune, Quince, Tomato (Green) produce ethylene and they are sensitive to ethylene gas.

Fruits & Vegetables Sensitive To Ethylene

The following fruits and vegetables are highly sensitive to ethylene gas, but they themselves do not emit ethylene.

Asparagus, Basil, Beets, Bok Choy, Broccoli, Brussels Sprouts, Cabbage, Chinese, Cabbage, early, Carrots, bunched, Cauliflower, Celery, Eggplant, Elderberries, Green Beans, Green Peas, Herbs, Leeks, Lettuce, Mushrooms, Parsnips, Peppers, hot chili, Persimmons, Pomegranates, Potatoes, Pumpkins, Radishes, spring, Rutabagas, Salad Mixes, Sprouts, Squashes, summer, Squashes, winter, Sweet Potatoes, Turnips, Watermelon, etc.do not produce ethylene but they are highly sensitive to it.

Fruits & Vegetables that DO NOT Produce Ethylene Gas

Artichokes, Cherries sweet, Chicory, Coconuts, Corn, sweet, Cranberries, Garlic, Ginger, Kohlrabi, Onions, Peppers sweet, Pomegranates, Rhubarb, etc. do not emit ethylene and are not sensitive to it.

Oranges produce very small amount of ethylene gas and are not sensitive to this gas.

How to tell if the mango is ripe?

Video on how to prevent bananas from ripening

Youtube video How to keep bananas fresh longer
Best fruits to grow in pots Video

References

1. Lelièvre, et al., Ethylene and fruit ripening, pdf
2. Ethylene - Wikipedia, the free encyclopedia
3. Curry, E.A. and M.E. Patterson. 1993. Controlling ethylene biosynthesis with natural compounds. Proc. Wash. State Hort. Soc.: 312-313.
4. Spoiled Rotten—How to Store Fruits and Vegetables,
www.vegetariantimes.com/article/spoiled-rotten-how-to-store-fruits-and-vegetables/
5. Bob Mueller, Using Ethylne, Potato Grower Magazine, August 2013 Issue Published online: Aug 04, 2013.
6. Engineering ToolBox! Fruits and Vegetables - Optimal Storage Conditions, www.engineeringtoolbox.com/fruits-vegetables-storage-conditions-d_710.html
7. California Fresh Market Advisory Board, Informational Bulletin No. 12, June 1, 1976.

Comments

Thanks a lot. Well researched and extensive. Content of your article far exceeds the matter I have been gathering from various sources during the last ten years. Kudos and keep it up. Thanks for your comments and appreciation. Is it ok to store squash next to onions? High humidity is the worst enemy for squash, so storing squash with onions can damage squash due to the release of moisture from onions. Thank you for your time and work on very thorough and comprehensive list. This page (whole site really) is Great!! I was just hoping for a list of ethylene producing produce, i did not expect to find such a complete reference. Thank you so much!