Download
slide1 n.
Skip this Video
Loading SlideShow in 5 Seconds..
Ice Cream PowerPoint Presentation

Ice Cream

131 Vues Download Presentation
Télécharger la présentation

Ice Cream

- - - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

  1. Ice Cream nano Nanocamp June 27, 2012 Chris Marin

  2. What is a liquid? • All liquids: • have a definite volume • conform to the shape of container • are not compressible • are made up of atoms that aren’t in fixed places

  3. What is a solid? • All solids: • have a definite volume • have a definite shape • are made up of atoms in fixed places

  4. What is ice cream?? • It has ice in the name, is it a solid? • Not quite! See how it took the shape of the glass? • Is it a liquid? • Not unless you wait to long! • It’s both!

  5. Colloids • A colloid is one phase mixed into another. • Ice cream is both a foam, emulsion, and sol!

  6. So what is ice cream? • In the above microscope image, A is air bubbles, C is ice crystals, F is fat, and S is a solution of liquid. • A big part of controlling ice cream’s texture is controlling how much air and ice are in the colloid.

  7. nano-ice cream • We will be using liquid nitrogen to rapidly make ice cream • Normally, ice cream takes hours to make, but liquid nitrogen is extremely cold (-321 °F, or 77 K) • The change in temperature when the liquid nitrogen is poured in should be so rapid that the cream doesn’t have time to change to ice • Instead, tiny nanometer sized ice crystals should form, like snow does on a very cold day. • This should make our ice cream very very smooth!