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Video Demo: Watermelon Caviar

I recently started a food science club at school with a fellow teacher.  It's a good way for me to try out new stuff with a small group of students, that I eventually want to incorporate into my classes.  It's like a real life R and D department.  I recently posted about a polymer called sodium alginate. I got a response from Earl Lee on how to make watermelon caviar. So I decided, let's try it out with an after school club.  It demonstrates a technique used in molecular gastronomy. A polymer (which is in one of our standards), sodium alginate, is mixed in with watermelon juice. The mixture is then carefully inserted, with a syringe, into a solution of calcium chloride. A chemical reaction happens between the calcium chloride and sodium alginate to form calcium alginate. The calcium alginate is not soluble in water and thus forms a gel around the outside of the watermelon juice. The calcium alginate watermelon spheres are edible. We then experimented with making spheres of cola using the same technique.  The students loved the more intense (not to mention the more sweet flavor which their palettes are more geared to) flavor of the cola.

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    Salubrious day ! Would you mind if I apportion your blog accompanying my facebook consort ? There’s a many of persons that I repute would truly relish your satisfy. Content allow me experience. Thank you
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    Im just soo interested with this! If you wanted tiny droplets, could you use a syringe with a needle?
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    ScienceFix - Science Fix - Video Demo: Watermelon Caviar
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    ScienceFix - Science Fix - Video Demo: Watermelon Caviar
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    The calcium chloride solution reacts with the sodium alginate to make a chemical polymer that is edible.
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    ScienceFix - Science Fix - Video Demo: Watermelon Caviar

Reader Comments (2)

Great video! I am current chemistry teacher education student and Illinois State and I am planning on doing something like this for a presentation that we have coming up. I bought a spherification kit a while ago but I haven't used it yet. Your video has given me some renewed enthusiasim to try it out. Keep up the great work, your blog is awesome!

- Justin

March 27, 2011 | Unregistered CommenterFutureTeacher

Thank you very much. Just dive right in and try it. It's lots of fun.

March 27, 2011 | Registered CommenterDarren Fix

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