Studies in Dumbness

[Salil Benegal]

originally posted by maureen:
I took delivery of some 07 Selbach z.s. spatlese "schmitt" that had gone fizzy and pushed out corks (that reminds me, Mayer was supposed to credit me for those).

Yikes - that's a real shame. 07 Schmitt is a lovely wine.

 

[Oswaldo Costa]

Thanks all. I finally "get" what I have been circling the caravans about while hesitating to conclude: if low or no sulfur were to be a "natural" wine requirement, then a Sauternes, an Auslese, or a Quarts de Chaume could never be.

 

[Ian Fitzsimmons]

Is SO2 also used to forestall the malo in RS-rich German wines?

 

[Oswaldo Costa]

originally posted by Ian Fitzsimmons:
Is SO2 also used to forestall the malo in RS-rich German wines?

I thought so, but David said no, filtration is used for that particular job. SO2 serves only to prevent bugs feasting on sugar.

 

[Ian Fitzsimmons]

Sorry, I should have read more carefully.

There are bugs that earn their living using sulfur as an oxidizing agent, but I gather that reaction is limited to anaerobic environments.

Non-sequitur, but in animal metabolism, does the oxidation of carbohydrates (leading to the conversion of ATP to ADP) create energy in the form of an electron flow (i.e., a current) or in some other way? (Some goes to heat, of course, but I mean energy used for work).

 

[MLipton]

originally posted by Ian Fitzsimmons:
Sorry, I should have read more carefully.

There are bugs that earn their living using sulfur as an oxidizing agent, but I gather that reaction is limited to anaerobic environments.

Define what form of sulfur you're talking about. Elemental sulfur is in no sense an oxidant.

Non-sequitor, but in animal metabolism, does the oxidation of carbohydrates (leading to the conversion of ATP to ADP) create energy in the form of an electron flow (i.e., a current) or in some other way? (Some goes to heat, of course, but I mean energy used for work).

Or perhaps a non-sequitur? The energy is released in the form of metabolic energy, the conversion of one chemical species to another. You're a bit cornfuzzled, though. Glycolysis converts glucose to pyruvate, thereby releasing energy that is harnessed to form ATP. ATP is the energy currency used in many different endothermic biochemical processes. For instance, ATPase converts ATP to ADP to drive the export of protons out of a cell to maintain proper pH balance in the cell.

Mark Lipton

 

[SFJoe]

originally posted by MLipton:
Elemental sulfur is in no sense an oxidant.

Sez you.

How about C+2S-->CS2? Formally an oxidation, no?

 

[MLipton]

originally posted by SFJoe:

originally posted by MLipton:
Elemental sulfur is in no sense an oxidant.

Sez you.

How about C+2S-->CS2? Formally an oxidation, no?

Hah! Leave it to a banker to cook the books. Internal redox is formally oxidation of carbon, but I think that the actual reaction has catalytic oxygen present to do the dirty work.

Mark Lipton

 

[SFJoe]

originally posted by MLipton:

originally posted by SFJoe:

originally posted by MLipton:
Elemental sulfur is in no sense an oxidant.

Sez you.

How about C+2S-->CS2? Formally an oxidation, no?

Hah! Leave it to a banker to cook the books.

Hasn't sulfur taken electrons from carbon, net?

Or take a more electropositive case. Fe+S-->FeS. Not an oxidation?

 

[MLipton]

originally posted by SFJoe:

originally posted by MLipton:

originally posted by SFJoe:

originally posted by MLipton:
Elemental sulfur is in no sense an oxidant.

Sez you.

How about C+2S-->CS2? Formally an oxidation, no?

Hah! Leave it to a banker to cook the books.

Hasn't sulfur taken electrons from carbon, net?

Or take a more electropositive case. Fe+S-->FeS. Not an oxidation?

When you're dealing with covalent bonds, who's to say where the electrons actually reside? After all, as QM entities, they are described as existing over all space, so localizing an electron on a particular atom is -- how to put this nicely? -- a charmingly 19th C view of subatomic particles. Ionic bonding is far more clear cut, so Cl2 + 2Na --> 2NaCl is decidedly an oxidation of Na and a reduction of Cl (so, I suppose you'd have me on S2 + 2Na ---> Na2S; mea culpa). This is why, beyond the simple exigencies of snarkiness, I made the "cooking the books" comment: it's an exercise in bookkeeping, really, how one chooses to apportion electrons in a covalent bond. Sure, we can use Pauling electronegativities to argue for this atom or that, but the electrons actually behave in far more fluid and less convenient ways. Transition metals are actually the poster children for this, since they can undergo both formal oxidation and reduction during a catalytic cycle, but does the metal actually gain or lose any electrons? Not so clear, often times.

Mark Lipton

 

[SFJoe]

I bow in agreement.

Though I do cherish my bookkeeping.

 

[Matteo Mollo]

Oxidation is the loss of electrons...i remember that from orgo!

fuck i hated orgo.

Favorite word i remember from organic chem and use only while playing scrabble:

enantiomer.

 

[Thor]

I thought so, but David said no, filtration is used for that particular job. SO2 serves only to prevent bugs feasting on sugar.

One Alsatian producer not known for fear of residual sugar but with a reputation for not taking criticism very well, bottled a very, very not-dry wine (and a very, very not-cheap one) with no filtration once. The results were predictable, but when questioned as to the practice, the reaction from the winemaking was (not paraphrasing much), "well, it's your [the consumer's] fault for not taking proper care of the wine."

I should have understood it as the omen it was, but I wasn't cynical enough in those days.

 

[Oswaldo Costa]

By not filtering, unwanted malos took place and the wine became flabby?

 

[Thor]

By not filtering, the wine ended up on more than one person's cellar floor.

 

[SFJoe]

originally posted by Oswaldo Costa:
By not filtering, unwanted malos took place and the wine became flabby?

Unwanted primary fermentation of sugar to ethanol and CO2, more explosively.

 

[Oswaldo Costa]

That's what I figured, but the thread had been about how filtration and SO2 have distinct functions, the first to prevent malos, the second to prevent refermentation. If the winemaker didn't filter but used adequate SO2, that should have only prevented malos, no? If the bottles exploded, shouldn't the culprit be insufficient SO2 rather than lack of filtering?

 

[SFJoe]

originally posted by Oswaldo Costa:
That's what I figured, but the thread had been about how filtration and SO2 have distinct functions, the first to prevent malos, the second to prevent refermentation. If the winemaker didn't filter but used adequate SO2, that should have only prevented malos, no? If the bottles exploded, shouldn't the culprit be insufficient SO2 rather than lack of filtering?

A sterile filtration can remove all fermenting organisms, whether MLF bacteria or primary alcoholic fermenting yeast (not all filtrations are so tight, of course). SO2 can shut down all the microbes as well.

 

[MLipton]

originally posted by Thor:

I thought so, but David said no, filtration is used for that particular job. SO2 serves only to prevent bugs feasting on sugar.

One Alsatian producer not known for fear of residual sugar but with a reputation for not taking criticism very well, bottled a very, very not-dry wine (and a very, very not-cheap one) with no filtration once. The results were predictable, but when questioned as to the practice, the reaction from the winemaking was (not paraphrasing much), "well, it's your [the consumer's] fault for not taking proper care of the wine."

I should have understood it as the omen it was, but I wasn't cynical enough in those days.

For these risks
All due precaution
Likely should be taken
Lest some unfortunate
End to your wine
Reassert itself

*Whew*
Mark Lipton

 

[Thor]

Clever.