Sugar and pH

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Tnuscan

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Lets say you've tested the must of your grapes, the pH is 3.2 , Brix is 19.

I want to raise the Brix to 22 so I add the sugar needed in a small amount of the must to desolve the sugar, then pour it back in.

Will this make the must more acidic since it will be going through fermentation?

Or in other words, would I need to adjust the acidity with calciuim carbonate for it to stay @ 3.2 pH ?

Thanks!!!
 
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Tnuscan

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The reason I ask the above question, is because I read where someone (on the internet) asked if adding sugar to a juice would change the pH and a chemist answered that it would not.

So I thought it would be the same wth making wine, and then someone informed me that if or when you added the yeast to ferment it into wine it lowered the pH.

Which would mean one would need to check or re-check after adding more sugar.

The muscidine I made started off with a pH of 3.2. I checked it in the field and after I crushed. The brix was 19 so I added enough sugar to raise it to 22brix, but I did not recheck the pH.

The other day I racked it and it was down to 3.01pH after I degassed it. A less accurate (or cheeper) meter read 2.9.

Thinking the fermentation would raise the pH, I was shocked to find it so low.

So,, was it adding the sugar that dropped it?


The BOLD underlined was brought from another post.
 

salcoco

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adding sugar buy it self will not affect the ph or the acid. However if you add water to dissolve the sugar before adding to the must it may change it a slight amount. Normally the procedure is check brix adjust as necessary. then check ph and acid and adjust as necessary.
during fermentation the co2 will cause an increase in carbonic acid which will lower the ph and raise the acid. although in rereading your statement you did degass the sample.I believe the carbonic acid would have affected you reading.
 

Tnuscan

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adding sugar buy it self will not affect the ph or the acid. However if you add water to dissolve the sugar before adding to the must it may change it a slight amount. Normally the procedure is check brix adjust as necessary. then check ph and acid and adjust as necessary.
during fermentation the co2 will cause an increase in carbonic acid which will lower the ph and raise the acid. although in rereading your statement you did degass the sample.I believe the carbonic acid would have affected you reading.

In my notes I have the pH after the addition of sugar, but by the large drop I figured If it was a fault of mine it would have to be the sugar addition.

I did not press them, and I have read that pressed wine will have a higher ph than the free run. But I didn't figure it would be that big of a difference.:?
 

Tnuscan

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adding sugar buy it self will not affect the ph or the acid. However if you add water to dissolve the sugar before adding to the must it may change it a slight amount. Normally the procedure is check brix adjust as necessary. then check ph and acid and adjust as necessary.
during fermentation the co2 will cause an increase in carbonic acid which will lower the ph and raise the acid. although in rereading your statement you did degass the sample.I believe the carbonic acid would have affected you reading.

I guess I will just make some next season and make it with a higher pH and mix the two together or sweeten it. It's not that bad after your eyes un-cross.
 

GreginND

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Either your initial measurements or your latest measurement is off. Field measurements may be prone to non-uniform sampling and acids that have not yet been extracted from the solid components of the grapes. Did you take a sample of the must and blend it really well to get the pH numbers?

Your more recent measurement many be off due to dissolved CO2 which Salcoco already mentioned.

Sugar addition should not have any affect on pH.
 

Tnuscan

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Either your initial measurements or your latest measurement is off. Field measurements may be prone to non-uniform sampling and acids that have not yet been extracted from the solid components of the grapes. Did you take a sample of the must and blend it really well to get the pH numbers?

Your more recent measurement many be off due to dissolved CO2 which Salcoco already mentioned.

Sugar addition should not have any affect on pH.

I believe the initial measurements had to be off then, I had too much faith in my older meter. I've since updated the meter, and I will get my ducks in a row for the next season. Oh well "we learn from our mistakes", I'll probably die a smart man because it seems all I make are mistakes. lol
 

Johny99

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This is one of the reasons I make wine. It isn't a mistake if nothing gets broken and nobody gets hurt. It is just another experience to increase knowledge:h
 

Al222

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Use 1.5 oz. of table sugar per gallon of projected liquid raises the ºBrix by 1°. Measure the amount of sugar needed and completely dissolve it into a small quantity of warm water The warm water ensures that the sugar will dissolve completely into the wine. This small amount of water will not be enough to dilute the wine. Also try to dissolve the sugar directly into the liquid from the must, but depending on how much you are adding, this may be difficult. Mix thoroughly into the must so that the sugar doesn‟t wind up sitting on the bottom. Havea good luck.
 
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