Author Topic: The Nature of the Yeast  (Read 10271 times)

0 Members and 1 Guest are viewing this topic.

Offline November

  • Registered User
  • Posts: 1879
  • Location: North America
  • Come for the food. Stay for the science.
    • Uncle Salmon
Re: The Nature of the Yeast
« Reply #40 on: October 05, 2006, 06:21:17 PM »
I think the use of the term "steam" may have led some people (including Pizza Shark) to think you were referring to it in the common sense as noted, for example, at wikipedia:

Wow.  Does anybody use a dictionary anymore when dealing with the definition of a term?  From Dictionary.com, the very first entry (indicating the most common usage) is:

1. water in the form of an invisible gas or vapor.

I concur with Jeff's conclusion as to the level expanding gasses contribute to a dough's rise in the oven.  Water vapor is most definitely the majority player in any instance.  In addition to what has already been discussed, CO2 is very compressible while water is not, and steam doesn't compress well.  It's just another attribute of water that allows it do so much work (from a physics standpoint).


Offline shango

  • Registered User
  • Posts: 344
  • Age: 41
  • Location: right here
Re: The Nature of the Yeast
« Reply #41 on: October 05, 2006, 07:19:53 PM »
I used to make hundreds of pizzas a day many years ago, and I can say that it's not absolutely essential.  In fact, regardless of how many pizzas either of us have made, we're talking about the constituent actions leading to dough rising in the oven, which is not like comparing angels and devils.  Whether it's by chemical reaction, metabolic process, or politicians billowing air, it's all still an observation of the same function: oven rise (or oven spring as some would call it).  Now if we we're talking about flavor, of course the comparison would be different.  However, even in that case, I doubt that having yeast alive when placing the pizza in the oven will make any difference since they die a quick death before you taste it anyway.  Flavor, as it relates to yeast, should be expressed as a function of yeast amount * available nutrition * metabolic rate * time.  Generally, the difference between the highly objective "good vs. bad" tasting crust is found between two points on a nonlinear scale.  It's not as easy as, "the yeast must be alive when in the oven."

Which leads me into my response for Peter.  I've pointed to several factors before that have relevance to your quandary.  At some point I may have to resort to a "grand metaphor" to explain the day in the life of yeast and how it relates to pizza crust, but for now I'll try to keep it as short as possible.  Yeast are much like any other living organism, they need food, water, and trace minerals for cellular respiration to occur.  They're also fond of space and nitrogen containing compounds for reproduction and colonization.  To make one comparison to farm animals for a moment, yeast are in competition for nutrients just like animals on a farm.  When lots of animals are confined in a small space, they become agitated, nervous, and even frightened.  The reason for this state of being is due to a concern over food supply.  When one animal spends all of its time near other animals, the animal is hardwired for concern over whether it will get the food it needs to survive.  This condition causes health problems for them (and eventually for us) as excess cholesterol is released in the body as a precursor to forming steroids which will provide the animal the aggressiveness to compete for the food.  Yeast act the same way, but with less hardwiring.  That is to say they don't react to stimuli as complex as social interaction, but they do react to their environment.  The more yeast you have within a defined space, the more they will be able to sense nutrient depletion in their surroundings.  When nutrients aren't as readily available due to overpopulation, the yeast react by producing chemicals within to compensate.  It's kind of like with animals that don't get enough protein in their diet, so their digestive system cannibalizes muscle tissue and tract lining.  As a result of nutrient depletion and chemical re-synthesis, the yeast become lethargic and respire at a slower pace.  Both the flavor and the CO2 levels suffer in the end.

Maybe sometime soon I will post a concise formula that can be used to determine the exact amount of yeast byproducts given the amounts of everything added to the dough.

you are brilliant!

I just make pizze for a living.

eh.
pizza, pizza, pizza

Offline shango

  • Registered User
  • Posts: 344
  • Age: 41
  • Location: right here
Re: The Nature of the Yeast
« Reply #42 on: October 05, 2006, 07:24:02 PM »
This will be my last post on this topic as I am at work and there are people waiting for me
to kill the yeast in their pizze for them. :pizza: :'( :-D

pizza, pizza, pizza

Offline varasano

  • Registered User
  • Posts: 712
  • Location: Atlanta (Bronx born and raised)
  • Seeking perfection
Re: The Nature of the Yeast
« Reply #43 on: October 05, 2006, 07:31:55 PM »
November, thanks for you help in this topic. I was fighting a lonely battle there for a while

Edan, go get 'em tiger.

:-)

Jeff

Offline pizzanapoletana

  • Registered User
  • Posts: 959
  • Location: London -UK
  • Pizza Napoletana as it was made in 1730!
    • Forno Napoletano - Pizza Ovens
Re: The Nature of the Yeast
« Reply #44 on: October 05, 2006, 07:36:52 PM »
Ever try to make a pizza with over risen dough?  It does not rise one bit..


Your not considering the problem of destroyed Gluten which do not trap the gasses anymore when cooking... It is not a yeast issue....

Try to re-form a dough ball after is over risen and let it rise again for a bit, you'll se how it rise in the oven.....

Ciao

Offline Pete-zza

  • Lifetime Member
  • Global Moderator
  • *
  • Posts: 22442
  • Location: Texas
  • Always learning
Re: The Nature of the Yeast
« Reply #45 on: October 05, 2006, 07:44:31 PM »
Does anybody use a dictionary anymore when dealing with the definition of a term

November,

I knew what Jeff was getting at because he and I had had an exchange on this topic before. I drew the distinction between water vapor and steam (from boiling water) only because Tom Lehmann of the AIB did in his email to me. On another occasion, Tom Lehmann indicated that pita bread is one of the few baked goods where the internal temperature during baking can get above 212 degrees F. What happens then, as I myself discovered when I first made pita breads, is that the pita bread will balloon up very quickly. Fortunately, pizzas coming out of the oven have an internal temperature of between 200-205 degrees F.

I use onelook.com, an aggregator of dictionaries, and when I did a search on "steam" I found definitions all over the place, although the two most common seemed to be the water vapor and steam (from boiling water) definitions. I can see how a non-technical person might not notice the difference.

Peter

Offline November

  • Registered User
  • Posts: 1879
  • Location: North America
  • Come for the food. Stay for the science.
    • Uncle Salmon
Re: The Nature of the Yeast
« Reply #46 on: October 05, 2006, 10:11:36 PM »
Peter,

The fault really lies with the English language.  Too many definitions have been accepted for the same term, which in part conflict with each other.  The original definition, and currently the most accepted, is: vapor.  The term itself is older than the Fahrenheit and Celsius temperature scales, so the water temperature certainly has nothing to do with the term.  It's all about phase change.  The water was a liquid, now it's steam.  The fact that a person can see the light-diffusing condensed form only proves that the space it occupies is more saturated than the surrounding air.  The same thing happens with any gas.

http://www.etymonline.com/index.php?term=steam

Jeff,

No problem.  I'm just interested in the truth as much as science can reveal.  Speaking of science, since your occupation is out in the open, and you seem to be grounded in scientific principles, I'll mention a little of what my background is.  My dual major in college was Biophysics and Computer Science.  Since college my career has included working in several disciplines, but most recently my work has been in Information theory and Mathematical physics.  It's basically an amalgam of software development and scientific research.  I'm essentially the "algorithm guy."

- red.november

Offline varasano

  • Registered User
  • Posts: 712
  • Location: Atlanta (Bronx born and raised)
  • Seeking perfection
Re: The Nature of the Yeast
« Reply #47 on: October 06, 2006, 12:37:09 AM »
Cool. My specialty is large scale frameworks and dealing with the principles which underly massive amounts of complexity, especially multiple dimensions of permuative variability (whatever the hell that means)

Offline PizzaByMaria

  • Registered User
  • Posts: 1
  • I Love Pizza!
Re: The Nature of the Yeast
« Reply #48 on: October 06, 2006, 10:06:48 AM »
Hi Shango:

I have heard great things about your pizza and the pic you have next to your name looks great. Can you tell us if you guys use American or Italian flour at your place?

Offline gabaghool

  • Lifetime Member
  • *
  • Posts: 513
  • Location: GLASTONBURY, CT
Re: The Nature of the Yeast
« Reply #49 on: October 29, 2011, 05:35:41 PM »
shango-

I know this is a very old thread, but I hope it gets answered.

I asked a similar question a while back.

So if I get this right.  You would mix a batch of dough, let it bulk rise at room temp, roll it into the fridge to let it double again...pull it out, portion, ball, and back overnight in the fridge.  Then out to the room, let the balls get to room temp and THEN make a pizza with it?

So, what problems do you see with a batch of dough, mixed, portioned, balled and straight inot the fridge for a few days, slowly fermenting, then pulled out and left to get to room temp before pounding and baking?  This is pretty much standard NY style of dough making?  Where do you see errors?

Thank  you very much for any info.