# Sodium Hydroxide and Phenolphthalein



## winemaker_3352 (Sep 5, 2012)

Does anybody know what the shelf life is for Sodium Hydroxide and Phenolphthalein??

I am getting some off readings from my TA test kit - I am waiting on my PH meter - should be here next week.


Normality = .10
NaOH used = 1.9ml
Sample Used = 3ml


*TA instructions say:*

Sample used X .25 = .475%

*But using this equation:*







*i get - *.57%

Not sure what to believe here...


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## ibglowin (Sep 5, 2012)

First off why are you not using a pH meter! 

You should get at least 6-9 months as long as its kept in a fridge or cool place and pretty full.

Thats a weird sample size. I use the More Wine TA test kit and IIRC it comes with 0.1N NaOH and requires a 5ml sample. The multiplication factor is 1.5

I would try it again with 5ml and use 1.5 as the factor.


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## winemaker_3352 (Sep 5, 2012)

I know i need a PH Meter - got one on order 

Not sure why - that was just what the TA instructions said to do..

Use 3cc(ml) sample - add 3-4 drops of Phenolphthalein - then add the NaOH - how ever many cc(ml) were used - multiply that by .25.

How does the sample size make a difference??

Is the equation above an accurate one??


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## winemaker_3352 (Sep 5, 2012)

Ok - so i tried using a 5ml sample.

Normality = .10
NaOH used = 2.4ml
Sample Used = 5ml

% TA * .25 = .60

ppt sulphiric * 1.5 = 3.75

These readings seem better to me - BTW this is for a Chilean Pinot Noir...


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## ibglowin (Sep 5, 2012)

If you used 2.4ml of (0.1N) NaOH for a 5ml sample then your TA is 

2.4 X 1.5 = 3.6 G/L

Which is pretty low.

I would not mess with it until you get your pH meter and use it as the referee. Your eye may be off.


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## winemaker_3352 (Sep 5, 2012)

I don't think that what you had is g/l - it is ppt sulphiric.

2.4 X 1.5 = 3.6 ppt sulphiric not g/l..

AT least that is what my instructions say..


For a Pinot it is not really low..

I have seen a lot of pinot's around:

Acid 5.57 g/L 
PH 3.64

So my TA was .60% or 3.6 ppt is not that far from these...


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## ibglowin (Sep 5, 2012)

I have no idea what you are talking about. There is no such thing as sulphiric. You are titrating tartaric acid to an endpoint with sodium hydroxide. Why don't you take a look at these instructions.

More Wine TA Test Instructions


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## winemaker_3352 (Sep 6, 2012)

I guess every test kit is different - I am just going off what the crosby and baker test kit says.

Parts Per Thousand (European) same as % tartaric just a different way of calculating it.

The crosby and baker instructions say to multiply by .25 to get % tartaric and multiply by 1.6 to get the ppt sulfuric...

I do like the instructions you gave though - a little more in depth on the color change to look for.

will try again tomorrow morning - but i think my best bet is to wait for my Milwaukee SM102 PH Meter!!!


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## BobF (Sep 6, 2012)

Jon - My kit is the same as yours. It includes conversions for both ppt sulphuric and g/l tartaric.

3ml sample and .1 NaOH. NaOH used X .25


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## ibglowin (Sep 6, 2012)

Anybody got a link to those instructions from CB? Maybe I can make heads or tails of it if I can take a look at it.


You are going to love the pH meter. It will be like a Microwave for sure (how did I ever live without it)


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## winemaker_3352 (Sep 6, 2012)

ibglowin said:


> Anybody got a link to those instructions from CB? Maybe I can make heads or tails of it if I can take a look at it.
> 
> 
> You are going to love the pH meter. It will be like a Microwave for sure (how did I ever live without it)


I know - i can't wait for it to come in!!

I tried finding those instructions online - no luck. Let me do some more searching, if i find it I will send it...


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## winemaker_3352 (Sep 6, 2012)

BobF said:


> Jon - My kit is the same as yours. It includes conversions for both ppt sulphuric and g/l tartaric.
> 
> 3ml sample and .1 NaOH. NaOH used X .25




Good - I am not crazy then


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## Julie (Sep 6, 2012)

roflmao, will I do have a ph meter but when I did not, the kit I used said to use 10 ml sample and .1 NaOH. NaOH used X .75!


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## BobF (Sep 6, 2012)

Here's a copy:


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## winemaker_3352 (Sep 6, 2012)

BobF said:


> Here's a copy:
> View attachment 5404




That's it!! Like i said before - all TA instructions are different.


But using the C&B I get:

2.2 * .25 = .55

Using Mike's instructions:

3.7 * 1.5 = 5.55

So they came out to be the same - the key was figuring out the color to look for when titrating a red wine.

I was reading when it turned grey - but thanks to Mike's instructions i found that was wrong - i needed to titrate until it turned a greenish color...


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## BobF (Sep 6, 2012)

My reds always turn grey. The only time I see green is when doing A/O


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## grapeman (Sep 6, 2012)

The new Vinmetrica 200 meter is $165 and is a combination pH meter and TA test kit. Take a 5 ml sample in a beaker, add 15 ml water, drip sodium hydroxide until it beeps as it reaches 8.2. Then you take ml NaOH used and multiply by two for g/L. About as simple as it gets and quick too!


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## winemaker_3352 (Sep 6, 2012)

grapeman said:


> The new Vinmetrica 200 meter is $165 and is a combination pH meter and TA test kit. Take a 5 ml sample in a beaker, add 15 ml water, drip sodium hydroxide until it beeps as it reaches 8.2. Then you take ml NaOH used and multiply by two for g/L. About as simple as it gets and quick too!



Yeah - I am currently waiting on my Milwaukee SM102 to come in. This is not a PH/TA combo - but I think I can get a TA reading from the PH tests..


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## grapeman (Sep 6, 2012)

Absolutely you can. I did it a lot and it works. The little extra money is worth it IMHO for the Vinmetrica. You can perform about 30 tests with the reagents and replacement Na0H is $15 - much cheaper than buying the kits for what they do.


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## BobF (Sep 6, 2012)

Does the Vinmetrica test for malic?


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## ibglowin (Sep 6, 2012)

I believe just TA as well as pH and SO2 of course if you get the full blown unit.


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## winemaker_3352 (Sep 6, 2012)

Just ordered my Vinmetrica's SC-200 pH/TA Wine Analyzer!!!

Woo hoo!! - hope this simplifies my titrations...


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