Mustard chemistry 2 (photobleaching and fluorescence)

追加: 2026-06-03

[00:00:01]The curcumin in turmeric and mustard is pH sensitive and it fluoresces. It's also light sensitive. Here we have mustard in packets and also smeared out and dried on a piece of paper.

[00:00:14]This is what the paper looks like after it has been placed out in the sun for about a day, bright sunlight. And uh we put rocks on the paper and you can see that some of the pack there's still some yellowish patches here where the rocks were, but a lot of it has sort of faded out where the sunlight hit it. This is more obvious when we put uh fluorescent light on it. See, this is what it looks like sort of to start out, all fluorescent.

[00:00:46]And here only the patches where that had been shaded from the sunlight are still fluorescent.