|MadSci Network: Biochemistry|
I did some research and discussed this issue with an expert in the field and cannot offer an explanation for this reaction. So, I conducted a little experiment: 1. I cut open an onion with a stainless steel kitchen knife and smelled the knife. The onion odor was present on the knife. 2. Rubbed the onion on my hand, applied the knife and the odor was removed. 3. Rubbed the onion on my hand and rinsed with water and the odor was removed. The test results are inconclusive. Onion contains compounds of Sulfur which is added to stainless steel to render free machining properties. Onion changes color when it reacts with acid and can be used as a kitchen pH indicator. Skin protien does not react with stainless steel. None of these facts gives a clue to why the odor is removed with stainless steel. Sorry but I cannot offer an explanation.
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