How to check SG TA and pH in freshly crushed must?

How to check SG TA and pH in freshly crushed must?

Post by Fishhea » Sun, 25 Sep 2005 11:31:00



I took some readings in some fresh must that was just crushed.
It seemed hard to check SG with a hydrometer, as there are lots of
particles in the must.  Seems this would skew the readings.

My initial readings.

TA .58
pH 3.80
SG 1.115

I added enough TA to increase it by 1%.  I also added meta, enzyme and
nutrient
After stirring up the must I took readings again.
TA .55
pH 4.05
SG 1.110

What is the best way to get a good sample of must for tests?
Does the material floating in the must effect the readings?

 
 
 

How to check SG TA and pH in freshly crushed must?

Post by Joe Sallusti » Sun, 25 Sep 2005 17:52:20


Yes, it does. The hydrometer is supposed to be in contact with fluid
only.  Just strain it, I have a 8 inch funnel with a screen that works
well for this.  You could use a cloth or something like that too.

Your nuber seem a little wierd, they went the wrong way on acids.  Was
it fermenting?  CO2 will skew the readings.

Joe

 
 
 

How to check SG TA and pH in freshly crushed must?

Post by Fishhea » Sun, 25 Sep 2005 22:39:13


Quote:

> Yes, it does. The hydrometer is supposed to be in contact with fluid
> only.  Just strain it, I have a 8 inch funnel with a screen that works
> well for this.  You could use a cloth or something like that too.

> Your nuber seem a little wierd, they went the wrong way on acids.  Was
> it fermenting?  CO2 will skew the readings.

> Joe

It was not fermenting..  I just crushed it and took readings.
I will be taking readings again tonight, and then add my yeast
 
 
 

How to check SG TA and pH in freshly crushed must?

Post by Fishhea » Mon, 26 Sep 2005 01:09:08


Quote:

> Yes, it does. The hydrometer is supposed to be in contact with fluid
> only.  Just strain it, I have a 8 inch funnel with a screen that works
> well for this.  You could use a cloth or something like that too.

> Your nuber seem a little wierd, they went the wrong way on acids.  Was
> it fermenting?  CO2 will skew the readings.

> Joe

I have one of these funnels and screens also... I never thought of using
it for that.  (I bought it for cider)

I strained the must and re-checked the numbers.
I will post these in a new thread

Thanks!

 
 
 

How to check SG TA and pH in freshly crushed must?

Post by Tom » Mon, 26 Sep 2005 01:32:49



Quote:
>I took some readings in some fresh must that was just crushed.
> It seemed hard to check SG with a hydrometer, as there are lots of
> particles in the must.  Seems this would skew the readings.

> My initial readings.

> TA .58
> pH 3.80
> SG 1.115

> I added enough TA to increase it by 1%.  I also added meta, enzyme and
> nutrient
> After stirring up the must I took readings again.
> TA .55
> pH 4.05
> SG 1.110

> What is the best way to get a good sample of must for tests?
> Does the material floating in the must effect the readings?

Your pH will rise as the potassium in the skins of the grapes diffuses into
the must.  You really need to get some tartaric in there pronto!  Your pH is
soaring.  Could this be Petite Syrah?

I've found the easiest way to pull juice samples from must is to push a
strainer down into the cap, let it fill with juice and suck out a sample
with a turkey baster.

Try taking the TA up to 0.70 (on the sample) and see what that does for the
pH.  Then _taste_ the juice.  Always do a sanity check by taste before
busting any big moves with tartaric.  Double check your calculations, do the
addition in portions and check in between portions to see if you're on
track.  It's a lot easier to add more tartaric than it is to remove it if
you overshoot.

Tom S

 
 
 

How to check SG TA and pH in freshly crushed must?

Post by Fishhea » Mon, 26 Sep 2005 02:10:24


Thanks for the comments Tom.

I added my new numbers from today in another thread...  These were after
I strained the juice from the pulp.

The grapes are Merlot and Zinfandel

Quote:
>>Does the material floating in the must effect the readings?

> Your pH will rise as the potassium in the skins of the grapes diffuses into
> the must.  You really need to get some tartaric in there pronto!  Your pH is
> soaring.  Could this be Petite Syrah?

> I've found the easiest way to pull juice samples from must is to push a
> strainer down into the cap, let it fill with juice and suck out a sample
> with a turkey baster.

> Try taking the TA up to 0.70 (on the sample) and see what that does for the
> pH.  Then _taste_ the juice.  Always do a sanity check by taste before
> busting any big moves with tartaric.  Double check your calculations, do the
> addition in portions and check in between portions to see if you're on
> track.  It's a lot easier to add more tartaric than it is to remove it if
> you overshoot.

> Tom S

 
 
 

How to check SG TA and pH in freshly crushed must?

Post by jom.. » Tue, 27 Sep 2005 02:22:00


Quote........ Just strain it, I have a 8 inch funnel with a screen that
works
well for this.  You could use a cloth or something like that too.
.......

Pantyhose works great.just fill a foot up and squeeze a bit to
strain.....my cab. sauv. was so thick with solids that to look at it I
was afraid it was all sugar.But after straining this way the Brix
measured 22-23....my Zin was 26 Brix...both very reasonable I
think.......