hutchndi

I just pulled the following from a browsed website:

"If sucrose has been incorporated into the dough, it is immediately
transformed by a yeast enzyme, the invertase, into glucose and fructose (the
two basic links composing sucrose are thus separated). When sucrose or
glucose are added to the dough, they are directly fermented before maltose.
This means that in such a dough, mainly sucrose or glucose are consumed by
the yeast. These sugars do not contribute to giving the bread a sweet taste
since they are partly consumed. "

(The article also states that 10% alcohol halts fermentation.)

I do things differently from the norm here and try to get my yeasties to
make allot of alcohol, hoping to get the champagne flavor to remain in the
bread, (when it works it wonderful) as opposed to sour, (some here might
think this would be better accomplished with commercial yeast. I tried a
little experiment, and commercial yeast does not seem to make the same
champagne smell as sourdough, so lets stick to sourdough) and this so far
seems best accomplished by adding something a little sweet and doing a long
fridge ferment. Peter Rinehart's "Crust & Crumb" also states that adding a
sweetener facilitates alcohol production, promoting beery flavor in yeast
breads. As I want to get as much alcohol in the dough as possible before
reaching a threshold, is there a way to measure or at least get an idea of
the alcohol content, other than the strong champagne smell?

With all the experimenting going on here with trying to get "sour" and
judging acidity, I thought we may have a chemist on board.

Also, when they say 10% halts fermentation, what does that mean, it kills
the yeast?

Hutch

mike avery

There is a limit of how high a concentration of its own waste products
any organism can tolerate.

Baker's yeast has a very low tolerance for alcohol. I am surprised that
the page said it was 10%, I had thought it was closer to 5 or 6%. I
know that it is too low a tolerance for many beers, and almost any
wine. Further, baker's yeast doesn't settle out well, so it's hard to
clarify beer or wine made with baker's yeast. And the final nail in the
coffin is that it doesn't give beer or wine a good flavor profile. (Or,
it tastes nasty.)

The reason baker's yeast works well in breads is that you don't get to
that high a level of alcohol. And it has a good flavor for breads,
though not as good a flavor as sourdough.

Since there are a number of different yeasts that can work in sourdough
starters, it would be hard to say "sourdough works up to XX% alcohol"
because most people don't know what sort of yeast is in their starter.

Mike

hutchndi

So it would be different levels for different starters. So experimentation
with my starter would be necessary of course, which is ongoing, but how do
people tell what percent alcohol is present? There must be a way, or they
would have no way of coming up with these statements. Acidity you can check
with PH tests am I right? (I have no idea really, I am thinking of litmus
paper or something you use to check you pool water).

hutchndi

mike avery

In brewing circles, you measure the specific gravity of the wort (for
beer) or must (for wine) before you innoculate it with yeast. Whenever
you are ready to test, you repeat the test, getting a new, and lower,
specific gravity. The difference represents the amount of sugar the
yeast ate, and from that you have a pretty good idea what the
concentration of alcohol is. There are some fairly simple tests to see
if the yeast have stopped working (your air lock is no longer active is
the basic test).

I'm not at all sure how this would translate into baking usage. I
frankly don't think that a bread would get up to that high a
concentration of alcohol. Remember, the carbon dioxide has risen the
bread..... getting to 10% alcohol in a liquid medium takes the yeast
several days, or longer, at room temperatures.

The thicker medium would inhibit the yeast, and the shorter fermentation
time would also be an issue that would keep such high alcohol levels
from being achieved. If you get a chance, sniff fermenting beer or
wine, you can smell the alcohol. Sniff bread. You smell yeast, or
sourdough starter. Not alcohol.

Mike


Mike

will

No, I don't think you're going about all wrong. But I do think the
focus on yeast is too heavy.

There is a major enzymatic chain of events that occurs during
fermentation and it is not an adjunct thing but a central series of
events. Occasionally Roy B. gets into it for a couple of hundred words
which probably makes half of the list nuts, but always entertains me.
You can search for his comments. Pick a word like amylase or maltose to
get started and then keep following the sugars or enzymes he mentions
with further searches.

Charles Perry dropped a nice piece of advice on you last month when he
suggested you do a long autolyse. He meant hydrate some flour and
retard it WITHOUT starter. My guess is, Brian Mailman, if he reads this
post, might be able to point you to some links that discuss the
specifics of what goes on, since unleavened chemistry involves a world
of kosher issues. There's about a 15 minute window to make matzos, for
example, before these enzymes begin performing leavening functions of
their own.

For a more general discussion, Peter Reinhart in "Bread Baker's
Apprentice" gets into some of this material in his "Pain Ancienne"
formula.

Then of course, there's Mike Avery with the BREAD THAT MUST NOT BE
NAMED. Which is another, excellent, chop at this longer, low
inoculation, world.

My own efforts differ from yours. I do not perform a longish initial
fermentation before I retard. I mix and chill. I'm not looking for any
starter fermentation during the retard... that's later.

The concept that ties these suggestions together is letting the flour
sit, wet, with no, or a very small, leavening innoculation. That way
the flour's native enzymes and starches get a head start in your dough.
I find that even when I make white bread, a small addition of FRESHLY,
I capitalized that for a reason, FRESHLY, ground white wheat, spelt or
barley grain, provides a significant flavor improvement. I get a better
aged smell... you might say champaigny. The finished bread does not
reflect a wheat, spelt or barley flavor, though it is invariably better
than a simple white flour dough.

So... my two cents here is to investigate the non-leavening world for
flavor. And Hutch, get a mill. You will see this differently when you
have grain, THE raw material, in your hands.

Will

brian mailman

18 minutes, but that has to do with a bit of numerical mysticism
involving an obsolete until recently alphabet more than anything
scientific. Google on 'gematria' and 'chai.'

I rather doubt that 3500 years ago, unless they were actually Raelians,
they had 'enzymes,' much less ways of measuring them.

B/

brian mailman

There's really no need to send me email and as well post... I'm going to
see your message either way and there's no need to clog up my mail box, thanks.

I'm fairly easily trollable.

I don't remember any of that on whatever site, sounds interesting. I
might have pointed you to an article on kashrut.com or kosherquest.org,
I don't remember. Look in the Passover sections.

B/

hutchndi

"Occasionally Roy B. gets into it for a couple of hundred words

Wow, just read the Roy's "Wine Lees" post. Makes me wonder if champagne
yeast can leaven bread... Hey whats the best way to search this stuff? I go
to:
http://groups-beta.google.com/group/rec.food.sourdough
(which until a few days ago I didnt even know existed, I thought you had to
use a newsreader program)
and type "Roy maltose" for instance.

hutch

dick adams

Not so easy if you don't know the A is for Adams.

Two-name IDs are very useful, unless you have a
really weird name.

Take Carl, for instance -- At r.f.s., Carl is Carl Griffith,
who posted very helpfully, and sent a fine start to any one
who sent him a SASE, and whose Oregon Trail culture is
still available ( www.carlsfriends.org ).

Is Carl West permitted to be Carl at r.f.s.? Well, I'd say yes
if he was willing to take on the load of distributing Carl's
culture. Otherwise he'd be wise, I think to use both of his
names. Also anybody named Bill or Joe or Mary etc.
-- Dick Adams
<firstname> dot <lastname> at bigfoot dot com
___________________
Sourdough FAQ guide at
http://www.nyx.net/~dgreenw/sourdoughfaqs.html

felix karpfen

Comments from a lurking chemist - possibly superseded and singularly
unhelpful:

1. Alcohol has no taste - try neat vodka.

2. Any alcohol that is in the risen dough when it goes into the oven
will have vanished by the time that the bread comes out. Boiling
point of alcohol is 78.5°C.

3. The flavours - "beery", "champagne" etc - are due to reactions of
the alcohol with other products of fermentation; these reactions
are speeded up by the presence of acids (low pH) and raised
temperatures.

4. I do not know what other ingredients, also produced during the
dough fermentations cycles, contribute to the flavour of the baked
bread. My guess is that they are many.

Felix Karpfen

--
Felix Karpfen
Public Key 72FDF9DF (DH/DSA)