About Ethylene GasEthylene (C2H2) is an odorless, colorless gas naturally produced and released by most fresh fruit and vegetables as a ripening agent. Ethylene gas is also an ever-present pollutant resulting from exhaust fumes from internal combustion engines (including propane-powered forklifts), improperly vented greenhouse heaters, industrial waste, etc… Ripening fruit is well known for producing ethylene. However, other plant tissues also produce this gas and can lead to decay and wilting. Even when cut from the growing plant, fruits, vegetables, and flowers are still alive and respiring. Gaseous respiration products of fruits and vegetables, production by normal healthy flower and plant tissue, chopped or damaged leaf tissue, and diseased leaves and tissues can be significant sources of ethylene.
The following methods should be used to ensure that ethylene-sensitive produce is not exposed:
- Ethylene producing items (such as apples, avocados, bananas, melons, peaches, pears, tomatoes…) should be stored separately from ethylene-sensitive ones (broccoli, cabbage, cauliflower, leafy greens, lettuce, etc.). Also, ethylene is emitted by engines. Propane, diesel, and gasoline powered engines all produce ethylene in amounts large enough to cause damage to the ethylene-sensitive produce items mentioned.
- Ventilate the storage area, preferably to the outside of the warehouse, on a continuous or regular basis to purge the air of any ethylene.
- Remove ethylene with ethylene absorbing filters. These have been proven in reducing and maintaining low ethylene levels. If ethylene damage is suspected, a quick and easy way to detect ethylene levels is with hand held sensor tubes. This will indicate if the above steps should be followed.
Ethylene has been scientifically proven to cause:
- Increase in respiration
- Water loss/weight loss
- Yellowing or spotting
- Production of more ethylene
- Accelerated ripening, ageing and decay
- Reduction in nutrient content (e.g. loss of vitamin C)
- Taste and aroma changes, off-flavors such as bitterness
- Loss of leaves and flowers, sprouting, toughening