July 16, 2019, 12:30:03 AM
Forum Rules: Read This Before Posting


Topic: Yeast and Aluminum - Physical Change or Chemical Change?  (Read 6481 times)

0 Members and 1 Guest are viewing this topic.

Offline Porr3773

  • Very New Member
  • *
  • Posts: 2
  • Mole Snacks: +0/-0
Yeast and Aluminum - Physical Change or Chemical Change?
« on: January 11, 2010, 11:33:52 AM »
My father and I have recently made bread. The dough consists of 1/2 tbsp of yeast, 2 cups of water, 1 1/2 tbsp of salt, and 4 cups of flour. We let the dough sit overnight in a bowl covered in tin foil to let it rise but when we get up in the morning there are little pinprick holes in the Aluminum foil. The yeast does give off CO2 so I'm assuming that this is the result of gas escaping but the holes are kind of blackish around the outside... I'm wondering of this is a chemical change. I can't think of any chemical equation that would have Al+3 reacting with CO2. The only thing I can think is Al(HCO3)3...but even then I hope I'm not putting that in my bread. What do you think?

Offline billnotgatez

  • Global Moderator
  • Sr. Member
  • ***
  • Posts: 3777
  • Mole Snacks: +208/-55
  • Gender: Male
Re: Yeast and Aluminum - Physical Change or Chemical Change?
« Reply #1 on: January 12, 2010, 05:05:34 AM »
I wonder if it is the metal reacting with the salt or an acid like carbonic acid. Sometimes when wiping an aluminum surface with water I get a blackish residue.

Offline Porr3773

  • Very New Member
  • *
  • Posts: 2
  • Mole Snacks: +0/-0
Re: Yeast and Aluminum - Physical Change or Chemical Change?
« Reply #2 on: January 12, 2010, 12:45:09 PM »
Hmm the dough would seem to be very basic, so that seems plausible. Veryy interesting I suppose. It almost seems like the dough has a mind of its own, when it runs out of oxygen to consume it goes searching...

Offline billnotgatez

  • Global Moderator
  • Sr. Member
  • ***
  • Posts: 3777
  • Mole Snacks: +208/-55
  • Gender: Male
Re: Yeast and Aluminum - Physical Change or Chemical Change?
« Reply #3 on: January 12, 2010, 10:50:24 PM »
I thought that yeast did anaerobic??

Sponsored Links