Naked Science Forum
Life Sciences => Plant Sciences, Zoology & Evolution => Topic started by: thedoc on 02/05/2013 17:30:01
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Theodosia Woo asked the Naked Scientists:
Dear Naked Scientists,
I heard from a friend that rubbing the cut ends of a cucumber can remove its bitterness. [1] I looked online and the general speculation is that the removal of bitterness is due to the reduction in cucurbitacin, a toxic compound concentrated at the stem end of a cucumber. [2] If this is true, how does the action of rubbing help?
Some say it is osmosis [3] (I'm assuming they actually mean diffusion here): Say if the rubbing action increases the temperature and hence the rate of diffusion, shouldn't cucurbitacin diffuse down the concentration gradient away from the stem end?
Others say simply cutting off the ends is sufficient and that the action of rubbing may even reintroduce the cucurbitacin into the cucumber [4]: But what would that white slimy liquid produced during rubbing be then?
If cucurbitacin is some sort of a stress-released compound [5], could it be that the cutting and rubbing also exert some level of stress, resulting in the transport of such compound towards the "site of injury� (Which leads to perhaps a more important question: what is the normal function of cucurbitacin in cucumbers?)
[1]
[2] http://extension.oregonstate.edu/gardening/cucumber-bitterness-explained
[3] http://answers.yahoo.com/question/index?qid=20070324070824AAw09jG
[4] http://www.quora.com/Cucumbers/In-Indian-households-to-remove-the-bitterness-of-cucumber-a-slice-from-either-side-is-cut-and-rubbed-to-get-a-white-scummy-paste-from-cucumber-the-bitterness-Does-it-make-any-sense
[5] http://www.foodsafetywatch.com/public/504print.cfm
Love the show (http://www.thenakedscientists.com/HTML/podcasts/),
Theo
What do you think?