WootBot


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Schooled in winemaking in both Germany and California, winemaker Scott Harvey was crucial to putting Amador County on the California wine map in the 1980s. After years spent propelling such wineries as Santino, Renwood, and Folie a Deux to success, he launched his own Scott Harvey Wines with his wife Jana in 2004. We're thrilled to have him take over the regular Wine.Woot guest blogger position. See his first post here.

We as wine makers do not make wine, Mother Nature does. It is a natural process of fresh juice to vinegar. By understanding the biochemistry and the life cycles of the organisms involved we can direct and halt the process at the point where the human species likes to drink it rather than at the vinegar stage where the fruit fly prefers it.

Ever since Louie Pasteur figured out that it was yeast and bacteria that convert juice to wine and vinegar, we have been able to determine the conditions needed to foster the growth of the organisms we desire and the retardation of those we don’t desire for the production of fine wine.

One of the best tools in determining the environment we want to create for Mother Nature to do her job in creating fine wine is monitoring pH. Basically, pH is the measurement of free hydrogen ion concentration in the solution. For some reason, and I don’t know why, they chose 7 for neutral pH. Maybe some wooter out there does know why and can tell us. Everything above 7pH becomes more and more basic as the OH ions increase and everything below 7pH becomes more and more acidic as the positive hydrogen (pH) ions increase. Wine is an acidic solution that is produced in the range of 2.8pH to 4.2pH.

Not until the late 80s was the development and reliability of the pH meter such that we could use it in daily winemaking. Therefore, before that we relied on the measurement of total acidity to tell us what we needed to know. Today, still many winemakers make their decisions on TA rather than pH. It was a German winemaker Ed Friedrich, winemaker for San Martin in the early 70’s that showed Dr. Richard Peterson, then winemaker for Monterey Vineyards, how important pH was. Monterey was a new high quality wine region with a particular problem of producing grapes with extremely high malic acid levels thus forcing the winemakers to find a new way to evaluate the wine. Ed showed us when we are tasting acidity we are really tasting pH. pH will predict taste much better than TA ever has.

Up until 1996 I made wine based on TA. In 1996 Dr. Peterson (my mentor) brought me to Napa Valley to take over Folie a Deux winery. It was at Folie a Deux winery that I learned how to use pH in making my decisions on creating the right environment so that Mother Nature would transform those wonderful grapes into the wines we all enjoy.  

This blog is really an introduction to the next blog that will explain how pH plays a role in developing either new world wines (Parker Wines) or old world wines (food wines). Stay tuned.


PetiteSirah


quality posts: 80 Private Messages PetiteSirah
ScottHarveyWines wrote:Basically, pH is the measurement of free hydrogen ion concentration in the solution. For some reason, and I don’t know why, they chose 7 for neutral pH. Maybe some wooter out there does know why and can tell us. Everything above 7pH becomes more and more basic as the OH ions increase and everything below 7pH becomes more and more acidic as the positive hydrogen (pH) ions increase. Wine is an acidic solution that is produced in the range of 2.8pH to 4.2pH.


I'm sure nematic will correct me, but:

pH is the activity of Hydrogen ions (H+, i.e., bare protons). pOH is the activity of Hydroxide ions (OH-). Adding acid to base yields a salt (which can be table salt, as when combining Hydrochloric Acid HCl and Sodium Hydroxide NaOH, in this case is a more general term for an ionic compound) + water + a frakload of energy. Where does the water come from? H+ & OH- together yield HOH (no charge), or H2O.

pH 7 was defined as neutral because, for room temperature liquids, pOH ≈ 14 - pH. Or, to put it another way, when water disassociates at room temperature, it's equal parts Hydrogen and Hydroxide ions and therefore "neutral".

In contrast, total (or titratable) acidity just yields a percentage of acid-by-weight or acid-per-volume; it provides no information about how "strong" the particular balance of tartaric, malic, & lactic acids are that comprise a particular wine -- i.e., how active the free hydrogen ions are.

Hail the victor, the king without flaw
Salute your new master ... Petite Sirah!


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lahargis


quality posts: 3 Private Messages lahargis

Cannot wait to be "schooled" on wine and pH.

I agree that with water at room temperature, the concentration of hydrogen ions is equal to the concentration of hydroxyl ions.

aandroyd


quality posts: 0 Private Messages aandroyd
PetiteSirah wrote:
pH 7 was defined as neutral because, for room temperature liquids, pOH ≈ 14 - pH. Or, to put it another way, when water disassociates at room temperature, it's equal parts Hydrogen and Hydroxide ions and therefore "neutral".



This is circular logic. 7pH was not 'defined' as neutral, it just naturally is neutral because of the physical constant of dissociation of water molecules. the multiplied concentrations of H+ and OH- always equal 10^-14 (i.e. 10^-7 H+ times 10^-7 OH- equals 10^-14 in a neutral solution) as the concentration of H+ goes up, OH- will go down, and vice versa (pH and pOH do the same thing, as the pH is simply the exponent of the concentration of hydrogen atoms)

-AJ

mtchem


quality posts: 0 Private Messages mtchem

So in water at room temperature there are 1x10^-7 Molar (this is a concentration term) of hydrogen ions (H). But that's a big number so to make it smaller they used -log. The p in pH means -log. So in pure water pH=7. Because of the negative log, things get turned around. So the MORE concentrated solution of hydrogen ions the LOWER the pH. The LOWER the concentration of hydrogen ions in solution the HIGHER the pH. Remember, this is concentration based, so the amount of solution matters too.
A vat of apple juice might have the same number to hydrogen ions in it as a glass of hydrochloric acid. But one you can drink and the other is toxic. So total amount of hydrogen might not be that useful. The pH of apple juice is about 4, where the pH of the acid is much lower.

nematic


quality posts: 6 Private Messages nematic
aandroyd wrote:This is circular logic. 7pH was not 'defined' as neutral, it just naturally is neutral because of the physical constant of dissociation of water molecules. the multiplied concentrations of H+ and OH- always equal 10^-14 (i.e. 10^-7 H+ times 10^-7 OH- equals 10^-14 in a neutral solution) as the concentration of H+ goes up, OH- will go down, and vice versa (pH and pOH do the same thing, as the pH is simply the exponent of the concentration of hydrogen atoms)



Given the amount of struggles I see college chemistry students go through trying to come to an understanding of pH, you're both much more correct than I'd say half of them would be on an average midterm. Yes, pH 7 = neutral is based on a rounding of the dissociation constant of water (kw) at - koi, 20C? - anyway, it varies some with temp. So yes, to recap, neutral = when concentration of H+ = concentration of OH-, which happens to occur, in water, when the molar concentrations of both is about 10^-7.

One little points - now the accepted way of representing the positive species is as the hydronium ion, H30+.

Also, I think one of the most confusing things in discussing pH is when people talk about more or less acidic at the same time as talking about higher or lower pH, as these trend in opposite directions. low pH = high acidity, high pH = low acidity.

maddprofessor


quality posts: 5 Private Messages maddprofessor
mtchem wrote:...
A vat of apple juice might have the same number to hydrogen ions in it as a glass of hydrochloric acid. But one you can drink and the other is toxic. So total amount of hydrogen might not be that useful. The pH of apple juice is about 4, where the pH of the acid is much lower.



pH is complementary to pOH. If apple juice has a pH of 4 it's pOH is 10. What you are referring to as the difference between t things with the same pH but different "toxicity" is pKa. A strong acid vs. a weak acid had to do with how easily the H+ will dissociate from the Cl- for example. pH only has to do with concentration, not the strength of an acid. You can have a dilute strong acid or a concentrated weak acid.

nematic


quality posts: 6 Private Messages nematic
maddprofessor wrote:pH is complementary to pOH. If apple juice has a pH of 4 it's pOH is 10. What you are referring to as the difference between t things with the same pH but different "toxicity" is pKa. A strong acid vs. a weak acid had to do with how easily the H+ will dissociate from the Cl- for example. pH only has to do with concentration, not the strength of an acid. You can have a dilute strong acid or a concentrated weak acid.



I think mtchem was referring to a difference in the H+ concentration, with the samel # of H+ in a large vat of apple juice as in a small vial of HCl.

thatguy314


quality posts: 7 Private Messages thatguy314
aandroyd wrote:This is circular logic. 7pH was not 'defined' as neutral, it just naturally is neutral because of the physical constant of dissociation of water molecules. the multiplied concentrations of H+ and OH- always equal 10^-14 (i.e. 10^-7 H+ times 10^-7 OH- equals 10^-14 in a neutral solution) as the concentration of H+ goes up, OH- will go down, and vice versa (pH and pOH do the same thing, as the pH is simply the exponent of the concentration of hydrogen atoms)



Looks like I was beat to the punch. And I always enjoy a moment to publicly correct my brother, because it's something he would love to do if he were me....

thatguy314


quality posts: 7 Private Messages thatguy314
nematic wrote:I think mtchem was referring to a difference in the H+ concentration, with the samel # of H+ in a large vat of apple juice as in a small vial of HCl.



It's that old analogy of heat versus temperature: which has more heat, a cup of freshly brewed coffee or an iceberg? The iceberg. But the coffee's hotter (has a higher temperature).

damightyanteater


quality posts: 12 Private Messages damightyanteater

I'm a bit confused. What's the difference between TA and pH?

    My last 5 woots:
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PetiteSirah


quality posts: 80 Private Messages PetiteSirah
thatguy314 wrote:Looks like I was beat to the punch. And I always enjoy a moment to publicly correct my brother, because it's something he would love to do if he were me....



Beaten.

Hail the victor, the king without flaw
Salute your new master ... Petite Sirah!


"Who has two thumbs and loves Petite Sirah?" ThisGuy!

PetiteSirah


quality posts: 80 Private Messages PetiteSirah
damightyanteater wrote:I'm a bit confused. What's the difference between TA and pH?



TA = amount of acids in wine (by weight)
pH = "strength" of acids in wine (as measured by activity of H+/H3O+ ions)

Hail the victor, the king without flaw
Salute your new master ... Petite Sirah!


"Who has two thumbs and loves Petite Sirah?" ThisGuy!

MaskedMarvel


quality posts: 11 Private Messages MaskedMarvel

Howard Johnson is right!

nematic


quality posts: 6 Private Messages nematic
PetiteSirah wrote:TA = amount of acids in wine (by weight)
pH = "strength" of acids in wine (as measured by activity of H+/H3O+ ions)



TA stands for "titratable acidity" but some refer to it as "total acid" to reflect that it measures all of the acid in a solution.
pH is a measure of the concentration of the H+ ion in a solution, which is also (allowing some chemetic (its like poetic) license here) the concentration of the "active" form of the acid in the solution.

Why two different numbers? well, if the wine just stayed in the bottle, you could probably report either number. However, once you put wine in the mouth, which has its own population of acids and bases, the two numbers really come into play. Wines with the same pH but different TA values can (and often will) have significantly different mouthfeel and other characteristics. I'd make more sense, but I'm typing this from a pub in boston, and I'm two pints into "brooklyn black chocolate stout" - a few more of these, and the picture of scott harvey on the right hand side of the page might just start talking to me

ddeuddeg


quality posts: 29 Private Messages ddeuddeg
PetiteSirah wrote:Beaten.



Somewhat of a paradox: in correcting him, you proved that he was correct.

"Always keep a bottle of Champagne in the fridge for special occasions. Sometimes the special occasion is that you've got a bottle of Champagne in the fridge". - Hester Browne


Ddeuddeg's Cheesecake Cookbook

brutherford


quality posts: 14 Private Messages brutherford

Staff

Wow! I have seen ALOT of forum discussions but this one is my favorite!!

gcdyersb


quality posts: 141 Private Messages gcdyersb
nematic wrote:TA stands for "titratable acidity" but some refer to it as "total acid" to reflect that it measures all of the acid in a solution.
pH is a measure of the concentration of the H+ ion in a solution, which is also (allowing some chemetic (its like poetic) license here) the concentration of the "active" form of the acid in the solution.



I am incredibly excited about this pH/TA discussion. I went the physics route after high school and only took a little bit of chemistry in college. I understand the basics of pH and TA, but need more info in the context of wine. I'm wary of wines in the 3.7+ pH range based on empirical data I've collected. But I don't have a full grasp of how TA affects a finished wine other than it sounds like it's typically a measure of the dominant acid species, tartaric acid.

Cabernet Franc: it's not just for blending! It's also for blogging.

mtchem


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maddprofessor wrote:pH is complementary to pOH. If apple juice has a pH of 4 it's pOH is 10. What you are referring to as the difference between t things with the same pH but different "toxicity" is pKa. A strong acid vs. a weak acid had to do with how easily the H+ will dissociate from the Cl- for example. pH only has to do with concentration, not the strength of an acid. You can have a dilute strong acid or a concentrated weak acid.



Weather something is a strong or weak acid is important, especially if you are trying to neutralize it. However, just because something is a weak acid doesn't mean it's not toxic. HF is a weak acid, and is extremely toxic (dissolve all of your bones kind of toxic).

themostrighteous


quality posts: 12 Private Messages themostrighteous
gcdyersb wrote:I am incredibly excited about this pH/TA discussion. I went the physics route after high school and only took a little bit of chemistry in college. I understand the basics of pH and TA, but need more info in the context of wine. I'm wary of wines in the 3.7+ pH range based on empirical data I've collected.


like the cab in the current offering...

gcdyersb wrote:But I don't have a full grasp of how TA affects a finished wine other than it sounds like it's typically a measure of the dominant acid species, tartaric acid.


ditto. i would very much appreciate further discussion of this as well as why (per Scott's post) pH is a better tool for the winemaker to use than TA. just my $0.02.

EDIT: and thanks to Scott for getting this fascinating discussion a-rolling. it warms my heart to see that so many of my fellow wineaux are also fellow geeks. truly!

do you know... what biodynamics is?

turndon


quality posts: 0 Private Messages turndon

Here's a link to a pretty good explanation of pH/TA as well as a brief explanaition the Henderson-Hasselbalch equation that explains the buffering capacity of the organic acids (tartaric, malic, lactic, citric, etc.).

http://people.ok.ubc.ca/neggers/Chem422A/Organic%20acids%20in%20wine.pdf

PetiteSirah


quality posts: 80 Private Messages PetiteSirah
mtchem wrote:Weather something is a strong or weak acid is important, especially if you are trying to neutralize it. However, just because something is a weak acid doesn't mean it's not toxic. HF is a weak acid, and is extremely toxic (dissolve all of your bones kind of toxic).



Whether.

Hail the victor, the king without flaw
Salute your new master ... Petite Sirah!


"Who has two thumbs and loves Petite Sirah?" ThisGuy!

LoonBoarder


quality posts: 7 Private Messages LoonBoarder
PetiteSirah wrote:Whether.



You missed the "alot" earlier.

Dude... wait, what?

mtchem


quality posts: 0 Private Messages mtchem
LoonBoarder wrote:You missed the "alot" earlier.



I think alot should be one word, like always. So I'm trying to use it in print/posts as much as possible The weather thing was just a typo, I only take on one foolish spelling quest at a time.

LoonBoarder


quality posts: 7 Private Messages LoonBoarder

But seriously, thanks to Scott for expounding on this aspect of wine making. I never realized how deep the science went in this field.

Dude... wait, what?

kblais


quality posts: 1 Private Messages kblais
gcdyersb wrote:I am incredibly excited about this pH/TA discussion. I went the physics route after high school and only took a little bit of chemistry in college. ...



Me too. About the only thing I remember from high school chemistry is Avagadro's number. I likely would have remembered more if we'd made some tasty wine instead of aspirin (although that was pretty neat).

thecar761


quality posts: 1 Private Messages thecar761
MaskedMarvel wrote:Howard Johnson is right!



Dr. Samuel Johnson's right about Olson Johnson being right!

boaz38


quality posts: 2 Private Messages boaz38
thecar761 wrote:Dr. Samuel Johnson's right about Olson Johnson being right!



Rebbervt!! hiccup burp

Tormouse


quality posts: 1 Private Messages Tormouse

But the real point is that at some specific temperature that is approximately room temperature, a pure water sample has 10 to the minus 7 hydrogens (H+ or H3O+ if you must) and 10 to the minus 7 Hydroxols (OH-)as well. Since there are equal numbers of them, neither has a predominant effect, and the water is therefore defined as neutral. In fact, any water solution that has equal numbers of H+ and OH- will have concentrations of 10 to the minus 7 H+ and 10 to the minus 7 (OH-)

Incidentally, what happens when you add an acid like HCl to pure water? The acid falls apart into H+ and Cl-. This adds extra H+ to the solution so the amount of H+ increases, and the hydrogen ion concentration might increase from 10 to the minus 2 instead of 10 to the minus 7. Since the pH is the negative of the log of the hydrogen ion concentration, the pH becomes 2. Another thing that goes on at the same time is that since there are a lot more H+ ions around than before, some of them go around grabbing a bunch of the (OH) ions to lock them up as H2O. Therefore there is less (OH) than before - to be precise, only 10 to the minus 12 instead of 10 to the minus 7. The rule here in simple english is that the hydrogen ion concentration [H+] times the hydroxol concentration [OH-] equals 10 to the minus 14, or in log form log([H+]) + log([OH-]) = -14

The organic acids have additional complications because when you put them in water, they don't fall apart completely. Therefore the pH does not necessarily fall as much as you might otherwise expect. This also means that there are some un-ionized Hydrogens lurking there that will make it perhaps unexpectedly difficult to raise the pH if you add a base to the solution.

Incidentally, I always thought the HF (hydrolfluoric acid) is wickedly strong - the stuff dissolves glass and has all sorts of wierd environmental effects (eg. its vapors kill pine trees). If you breath it, it will do a number on you. Does some one know something about how it ionizes that I don't know?

mtchem


quality posts: 0 Private Messages mtchem
Tormouse wrote:But the real point is that at some specific temperature that is approximately room temperature, a pure water sample has 10 to the minus 7 hydrogens (H+ or H3O+ if you must) and 10 to the minus 7 Hydroxols (OH-)as well. Since there are equal numbers of them, neither has a predominant effect, and the water is therefore defined as neutral. In fact, any water solution that has equal numbers of H+ and OH- will have concentrations of 10 to the minus 7 H+ and 10 to the minus 7 (OH-)

Incidentally, what happens when you add an acid like HCl to pure water? The acid falls apart into H+ and Cl-. This adds extra H+ to the solution so the amount of H+ increases, and the hydrogen ion concentration might increase from 10 to the minus 2 instead of 10 to the minus 7. Since the pH is the negative of the log of the hydrogen ion concentration, the pH becomes 2. Another thing that goes on at the same time is that since there are a lot more H+ ions around than before, some of them go around grabbing a bunch of the (OH) ions to lock them up as H2O. Therefore there is less (OH) than before - to be precise, only 10 to the minus 12 instead of 10 to the minus 7. The rule here in simple english is that the hydrogen ion concentration [H+] times the hydroxol concentration [OH-] equals 10 to the minus 14, or in log form log([H+]) + log([OH-]) = -14

The organic acids have additional complications because when you put them in water, they don't fall apart completely. Therefore the pH does not necessarily fall as much as you might otherwise expect. This also means that there are some un-ionized Hydrogens lurking there that will make it perhaps unexpectedly difficult to raise the pH if you add a base to the solution.

Incidentally, I always thought the HF (hydrolfluoric acid) is wickedly strong - the stuff dissolves glass and has all sorts of wierd environmental effects (eg. its vapors kill pine trees). If you breath it, it will do a number on you. Does some one know something about how it ionizes that I don't know?



HF (hydrofluoric acid) is wickedly dangerous, but is still a weak acid. Which is to say, it has a small equilibrium constant. Basically, when you put it in water very little of it will fall apart into H+ and F-. It's dangerous because F- is very reactive! It will pull all the calcium (Ca) from your body to make CaF2, which means bye-bye bones and cells.

ozwine


quality posts: 0 Private Messages ozwine

It was nice to hear good things about Dr. Peterson. He was responsible for the weirdest (and hardest to sell) wine in my 30 years in the business. He brought Monterey Vineyards to my wholesaker as part of the Heublein Taylor California Cellars package.
I don't know why but he presentented a Botrytis Pinot Noir as the flagship wine. We bought 28 cases and couldn't sell the d..n stuff. Hell, I couldn't even drink it.
As I remember, the rest of the reds had the Monterey "greenies", but as a bulk restaurant house wine -- TCC was worth it.

wombativ


quality posts: 1 Private Messages wombativ
themostrighteous wrote:ditto. i would very much appreciate further discussion of this as well as why (per Scott's post) pH is a better tool for the winemaker to use than TA. just my $0.02.

EDIT: and thanks to Scott for getting this fascinating discussion a-rolling. it warms my heart to see that so many of my fellow wineaux are also fellow geeks. truly!



For the most part, TA only affects wine sensory characteristics. It won't directly correlate to pH due to the effects of K+ and CA++ ions in the must/wine. This ion concentration dictates the extent of H+ exchange in the wine, and thus the pH. The pH itself affects a number of properties in a wine, including the effectiveness of primary and secondary fermentations, protein stability, and tartrate stability. By far the most important reason pH is monitored however, is that it controls what microbes can grow in solution. At typical wine pH, very few yeasts/bacteria are able to grow, none of which are pathogenic. They higher the pH gets, the more organisms are able to grow. It also dictates the amount of sulfur dioxide (the standard wine making antimicrobial) that is present in solution in "molecular" form. It takes significantly more SO2 at high wine pH (3.6-4.2) to control unwanted growth than would be required at lower pH.

SonomaBouliste


quality posts: 238 Private Messages SonomaBouliste
themostrighteous wrote:ditto. i would very much appreciate further discussion of this as well as why (per Scott's post) pH is a better tool for the winemaker to use than TA. just my $0.02.

EDIT: and thanks to Scott for getting this fascinating discussion a-rolling. it warms my heart to see that so many of my fellow wineaux are also fellow geeks. truly!




I tkink this did get a thorough discussion sometime last year (does polarbear22 have a subject index addendum to his compilation yet?). pH affects microbiological stability, SO2 effectiveness, color, aromas, protein and tannin stability as well as perception of tartness. TA (if you correct for pH shift due to changes in TA) affects only perception of tartness. One of winemakers' worst nightmares is high pH + high TA - the wine can be both tart and not terribly stable.

polarbear22


quality posts: 35 Private Messages polarbear22
SonomaBouliste wrote:I tkink this did get a thorough discussion sometime last year (does polarbear22 have a subject index addendum to his compilation yet?). pH affects microbiological stability, SO2 effectiveness, color, aromas, protein and tannin stability as well as perception of tartness. TA (if you correct for pH shift due to changes in TA) affects only perception of tartness. One of winemakers' worst nightmares is high pH + high TA - the wine can be both tart and not terribly stable.


No subject index. Better figure out how to add that. But it should be searchable for subjects.

EDIT: Page 140 of the PDF in my link below.

Polar bears are meant to be clever, very clever. They are the Einsteins of the bear community. - Anonymous
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SonomaBouliste


quality posts: 238 Private Messages SonomaBouliste
polarbear22 wrote:No subject index. Better figure out how to add that. But it should be searchable for subjects.

EDIT: Page 140 of the PDF in my link below.



U R 2 much

polarbear22


quality posts: 35 Private Messages polarbear22
SonomaBouliste wrote:U R 2 much


I try. I try.

Polar bears are meant to be clever, very clever. They are the Einsteins of the bear community. - Anonymous
Please donate to the 2014 MS Bike Ride
Want to read what SonomaBouliste has to say about wine?
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mkelley2


quality posts: 0 Private Messages mkelley2

Wow! I'm impressed by all you scientists out there. I took the English & Philosophy route in college, so my epigram on the subject would be that I like wines with low acidity with my dark chocolate.

EPIGRAM, n. A short, sharp saying in prose or verse, frequently characterized by ACIDITY or acerbity and sometimes by wisdom.

...key word being "sometimes."

INTLGerard


quality posts: 58 Private Messages INTLGerard

Guest Blogger

A short interruption to the ongoing and informative PhD discussions on pH.

***
CONGRATS to Scott Harvey on the impressive showing at this years 2009 ZAP festival. That is an impressive group of top Zin producers to compete with. Kudos to your efforts!

Deb1234


quality posts: 0 Private Messages Deb1234
PetiteSirah wrote:I'm sure nematic will correct me, but:

pH is the activity of Hydrogen ions (H+, i.e., bare protons). pOH is the activity of Hydroxide ions (OH-). Adding acid to base yields a salt (which can be table salt, as when combining Hydrochloric Acid HCl and Sodium Hydroxide NaOH, in this case is a more general term for an ionic compound) + water + a frakload of energy. Where does the water come from? H+ & OH- together yield HOH (no charge), or H2O.

pH 7 was defined as neutral because, for room temperature liquids, pOH ≈ 14 - pH. Or, to put it another way, when water disassociates at room temperature, it's equal parts Hydrogen and Hydroxide ions and therefore "neutral".

In contrast, total (or titratable) acidity just yields a percentage of acid-by-weight or acid-per-volume; it provides no information about how "strong" the particular balance of tartaric, malic, & lactic acids are that comprise a particular wine -- i.e., how active the free hydrogen ions are.



Deb1234


quality posts: 0 Private Messages Deb1234

Hi Scott from Pittsburgh PA too much fun finding you on Woot!! this is just your place!

Get that zork cork on woot they'll love it.

Deb and Mike