Ethylene gas and bananas

[jensenbreck]

Hi,
I am doing my science fair project and I need to measure the amount of ethylene gas bananas produce. I have been researching and I know that a gas chromatography set can be used to measure ethylene gas but they are really expensive and too complicated for what I am doing. I was wondering if there are any easy ways to simply get a recording of the amount of ethylene gas there is in a box that contains a banana???
Please help me because If there is no easy way to measure the ethylene gas than I might have to re-think my whole assignment and I don't have much time left.
Thank you

[rb6banjo]

This seems pretty ambitious. Without a gas chromatograph, you're at the mercy of measuring the "total gas produced". You also need a gas-tight vessel to contain your bananas. If a lot of gas is produced, you might be able to approximate the amount by displacement with a balloon or something to capture the pressure increase in your vessel. If the ethylene production is small, the balloon approach will not be sensitive enough.

I can see this being a very tricky exercise. You might consider choosing a different experiment.

[GOM]

The amount of ethylene gas produced during ripening is so small that it would be impossible to measure by simple gas volumetric measuring methods.

You would need a sensitive and selective ( other gases are also produced) approach like gas chromatography

Interestingly the identical query to yours ( word for word!!? ) was posted here in 2015

https://www.sciencebuddies.org/science- ... hp?t=14316

The suggested approach on this site using ethylene gas detector tubes would also end up being too expensive for you

As rb6banjo said, you should consider another project.

[osp001]

You might be able to use a biological indicator, although it would be tricky in that it's pretty binary: either the ethylene is there at a given level, or it's below. Dianthus (carnations) are more sensitive to ethylene than any other flower, from what I know, something like single-digit ppb levels to cause petal wilt.

Good paper on the subject:

http://ucanr.edu/datastoreFiles/234-950.pdf

Doing gas dilutions (with presumably ethylene-free air) to guesstimate ethylene levels is probably prohibitively difficult, however.

[MSCHemist]

I wonder if there is some sort of in headspace in tube derivatization you could use to improve sensitivity. Perhaps bromination or dimethyldisulfide adducts.