checking acid levels
 

Hello everyone,
I've been going along and making my wine (& enjoying it too), but I thought
I should expand my skills to checking acid levels. Up until this point, I
really wanted to make sure I felt confident in the basics, but after tasting
a raspberry wine and a tart cherry wine (both tastes could be due to the
fruit)- I think I should be concerned with acid levels. I was wondering
what test kits you think are the best, and any other tidbits of helpful info
would be greatly appreciated. Thanks in advance.
Darlene

checking acid levels
 

"Dar V" > wrote "I was wondering what test kits you think are
the best, and any other tidbits of helpful info would be greatly
appreciated. Thanks in advance.

Darlene - I like the kit I use. Go to www.piwine.com and check out their
Deluxe Acid Testing Kit. You might not need everything that comes with the
kit so you can buy various components. Be sure to get the buret with the
teflon stopcock...makes it easier to add single drops of NaOH solution as
you get near the titration end point (I got cheap years ago and didn't get
the stopcock...always regretted it).

You will need a pH meter to do proper acid titrations. I bought mine from
Omega. A friend in our wine club just bought a meter from Morebeer.com.

Bill Frazier
Olathe, Kansas

checking acid levels
 

Dar,

I would agree with William using a pH meter. I bought a nice pH meter from
a chemical supply house for $80. It reads to the hundredths place and
accurate to .1. Plus you can measure the actual pH of the wine. Bonus.
There is a procedure to follow for titrating when the pH meter goes to 8.2,
it is the point where your NaOH used is the TA of your wine. Or if you
will, the point where the color change takes place. I have a written
procedure I will see if I can find and post it.

Lee

"Dar V" > wrote in message
...
> Hello everyone,
> I've been going along and making my wine (& enjoying it too), but I
thought
> I should expand my skills to checking acid levels. Up until this point, I
> really wanted to make sure I felt confident in the basics, but after
tasting
> a raspberry wine and a tart cherry wine (both tastes could be due to the
> fruit)- I think I should be concerned with acid levels. I was wondering
> what test kits you think are the best, and any other tidbits of helpful
info
> would be greatly appreciated. Thanks in advance.
> Darlene
>
>

checking acid levels
 

"LEE WEISS" > wrote in message >.. .
> Plus you can measure the actual pH of the wine. Bonus.
> There is a procedure to follow for titrating when the pH meter goes to 8.2,

I currently use a pH meter to check my t.t.a. also. But the blue
solution bottle says to take the reading when the pH = 7.0. I never
questioned it because I thought that 7.0 was the neutral reading.

Should I be taking the reading at 8.2, and if so "Why"?

Thanks,
Gus Calandrino

checking acid levels
 

I used one of the cheapo kits you get at any wine supply for years. The
work adequately with whites and adequately with reds with a pH meter. Last
year I got one of the deluxe kits from PI and I love it. But you can
certainly use one of the cheap kits if you are not sure about spending the
extra money. Then when you get up to 10-15 batches a year totaling 90-100
gals., you might want to get more serious. (But you don't have to.)

Ray

"William Frazier" > wrote in message
...
>
> "Dar V" > wrote "I was wondering what test kits you think
are
> the best, and any other tidbits of helpful info would be greatly
> appreciated. Thanks in advance.
>
> Darlene - I like the kit I use. Go to www.piwine.com and check out their
> Deluxe Acid Testing Kit. You might not need everything that comes with
the
> kit so you can buy various components. Be sure to get the buret with the
> teflon stopcock...makes it easier to add single drops of NaOH solution as
> you get near the titration end point (I got cheap years ago and didn't get
> the stopcock...always regretted it).
>
> You will need a pH meter to do proper acid titrations. I bought mine from
> Omega. A friend in our wine club just bought a meter from Morebeer.com.
>
> Bill Frazier
> Olathe, Kansas
>
>

checking acid levels
 

Hi Gus,

You should indeed be titrating to a pH of around 8.2. This is because as
you titrate your wine with NaOH you are creating salts of weak acids, namely
Sodium Tartrate and Sodium Malate. These salts, since they were formed by
the reaction of a weak acid and a strong base, are themselves weakly basic
and provide a endpoint pH above 7.0, typically about 8.2. If you want to be
more precise, you can make a plot of pH vs. mL NaOH as you titrate. The
endpoint of the titration can be taken as the inflection point of the
resulting curve. From my own experience, and countless others I assume, 8.2
is a pretty good number to shoot for.

CHEERS!

Aaron

"gus" > wrote in message
om...
> "LEE WEISS" > wrote in message
>.. .
> > Plus you can measure the actual pH of the wine. Bonus.
> > There is a procedure to follow for titrating when the pH meter goes to
8.2,
>
> I currently use a pH meter to check my t.t.a. also. But the blue
> solution bottle says to take the reading when the pH = 7.0. I never
> questioned it because I thought that 7.0 was the neutral reading.
>
> Should I be taking the reading at 8.2, and if so "Why"?
>
> Thanks,
> Gus Calandrino

checking acid levels
 

checking acid levels
 

I work in a lab and we have 4 ph meters of different varieties we also have
cupboard full of ph strips and nitrate strips. But what ph does my wine need
to be :-( lol. Also do you people calibrate you ph meters because they drit
out alot we do 5 point calibrations on ours ever morning. Even our top rig
whic is acurate to .001 and compensates for temperature to .01 of a degree
drifts out of claibration by the end of the day. Have wine makeing
"Mark Willstatter" > wrote in message
om...
> (gus) wrote in message
. com>...
> > "LEE WEISS" > wrote in message
>.. .
> > > Plus you can measure the actual pH of the wine. Bonus.
> > > There is a procedure to follow for titrating when the pH meter goes to
8.2,
> >
> > I currently use a pH meter to check my t.t.a. also. But the blue
> > solution bottle says to take the reading when the pH = 7.0. I never
> > questioned it because I thought that 7.0 was the neutral reading.
> >
> > Should I be taking the reading at 8.2, and if so "Why"?
> >
> > Thanks,
> > Gus Calandrino
>
> The only real reason titration is done to pH 8.2 is that the
> conventional endpoint for titration is to look for color change using
> phenolphthalein as an indicator solution, which happens at pH 8.2. pH
> 7.0 would probably make more sense but TA is defined that way, at
> least in the US. As a purely practical matter, you probably won't
> observe a huge difference between using pH 7.0 and 8.2 as an endpoint;
> since pH is a logarithmic scale, it takes roughly 10x more NaOH to get
> you from pH 3 to 4 than it does from 4 to 5, ten times more from 4 to
> 5 than 5 to 6 and so forth. In other words, it will take the vast
> majority of the NaOH you add during titration to get you from pH 3.5
> to 7.0 and a tiny amount to go from 7.0 to 8.2, probably not enough to
> significantly affect your titration result.
>
> - Mark W.