house vs sweetness

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JB vintage
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house vs sweetness

Post by JB vintage »

Has anyone made or seen a more extensive comparison of house style by degree of sweetness? That Graham is sweet and Dow dry I know but it would be very interesting if anyone has more comprehensive information and/or measurements about the major houses and how they compare in terms of sweetness.
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Re: house vs sweetness

Post by Glenn E. »

That's the reputation for Graham and Dow, but I've been told that the range between them is actually pretty narrow. Something like 70 g/l for Dow and 90 g/l for Graham, with most other Ports falling in a pretty narrow range right around 80 g/l.

No idea whether or not those numbers are actually true, though, as I've seen no actual measurements.
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Re: house vs sweetness

Post by g-man »

Glenn E. wrote:That's the reputation for Graham and Dow, but I've been told that the range between them is actually pretty narrow. Something like 70 g/l for Dow and 90 g/l for Graham, with most other Ports falling in a pretty narrow range right around 80 g/l.

No idea whether or not those numbers are actually true, though, as I've seen no actual measurements.
70-90 g/l of residual sugar sounds very low even for ports that don't have as much residual sugar as expected.

I can't seem to find the post, but I recall one of the Symington's divulging the baume of the wines of either the 2007 or 2009 vintage (unfortunately it's just a comparison of density, but it does have a correlation to residual sugars)
and it shows that on the typical year teh grahams has a higher baume then the dows.

nm

viewtopic.php?f=1&t=6805&p=56602&hilit=baume#p56602

julian posted it
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Re: house vs sweetness

Post by Glenn E. »

g-man wrote:
Glenn E. wrote:That's the reputation for Graham and Dow, but I've been told that the range between them is actually pretty narrow. Something like 70 g/l for Dow and 90 g/l for Graham, with most other Ports falling in a pretty narrow range right around 80 g/l.

No idea whether or not those numbers are actually true, though, as I've seen no actual measurements.
70-90 g/l of residual sugar sounds very low even for ports that don't have as much residual sugar as expected.
Baume doesn't translate easily to g/l, so I can't really understand what Julian's table represents. Is 3.4 - 3.8 a wide range? Is it sweet? It means nothing to me.

70-90 g/l is a lot of residual sugar. Sweet wines start at ~45 g/l, as I recall.

PX Sherry, which is practically syrup, is something like 200+.
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Re: house vs sweetness

Post by g-man »

Glenn E. wrote:
g-man wrote:
Glenn E. wrote:That's the reputation for Graham and Dow, but I've been told that the range between them is actually pretty narrow. Something like 70 g/l for Dow and 90 g/l for Graham, with most other Ports falling in a pretty narrow range right around 80 g/l.

No idea whether or not those numbers are actually true, though, as I've seen no actual measurements.
70-90 g/l of residual sugar sounds very low even for ports that don't have as much residual sugar as expected.
Baume doesn't translate easily to g/l, so I can't really understand what Julian's table represents. Is 3.4 - 3.8 a wide range? Is it sweet? It means nothing to me.

70-90 g/l is a lot of residual sugar. Sweet wines start at ~45 g/l, as I recall.

PX Sherry, which is practically syrup, is something like 200+.
Sauternes sit in the 130-180 range.
7 pt Tokaji is 260+
PX sherry is 200+
ice wine is typically in 160-200+
german TBA is 150+

baume is relative

3.4 to 3.8 means that
the Grahams 2011 is going to have 11% more residual sugar thant he dows 2011
this is approximated because we will assume that the alcohol is going to be at 20%.

if you take out the alcohol content, then it's a fair approximation that the other "stuff" that affects density in the wine is the residual sugar.

so if the dow was at 90, the grahams would be ~100

I forgot where i saw it but I recall teh dow around mid 90s and the grahams typically around 110 mark

FYi the 2011 Quevedo is at 100 g/l residual sugar
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Re: house vs sweetness

Post by jdaw1 »

Glenn E. wrote:Baume doesn't translate easily to g/l, so I can't really understand what Julian's table represents. Is 3.4 - 3.8 a wide range? Is it sweet? It means nothing to me.
[url=http://theportforum.com/viewtopic.php?p=56602#p56602]Here[/url] jdaw1 wrote:Baumé on x axis, total acidity on y, for those 2011 Vintage Ports for which data available, and some others.
Image

Please let me know of other data that can be added.
My chart is from data published by the port houses. What, if anything, that data means ahh, a different question, but not one to ask me.
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Re: house vs sweetness

Post by g-man »

jdaw1 wrote: Please let me know of other data that can be added.
My chart is from data published by the port houses. What, if anything, that data means ahh, a different question, but not one to ask me.[/quote]

it means that we are missing you state side and would require your presence sometime soon so that we can discuss such important matters
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Re: house vs sweetness

Post by Glenn E. »

g-man wrote:Sauternes sit in the 130-180 range.
7 pt Tokaji is 260+
PX sherry is 200+
ice wine is typically in 160-200+
german TBA is 150+
All of those are much thicker in texture than Port - many approaching that of syrup, while 7 pt Tokaji is syrup - which supports what I'd heard. Port is not as sweet as any of those wines, nor is it as thick and syrupy.
g-man wrote:I forgot where i saw it but I recall teh dow around mid 90s and the grahams typically around 110 mark

FYi the 2011 Quevedo is at 100 g/l residual sugar
So not too far off.
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Re: house vs sweetness

Post by Glenn E. »

g-man wrote:
jdaw1 wrote:My chart is from data published by the port houses. What, if anything, that data means ahh, a different question, but not one to ask me.
it means that we are missing you state side and would require your presence sometime soon so that we can discuss such important matters
March, perhaps?
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Re: house vs sweetness

Post by LGTrotter »

It seems to me to be as much about the vintage as the shipper. I think of Warre as having a dry style but the 85 Warre seems much sweeter than the 83 Graham. And Dow 85 is as sweet as anything of that year.
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Re: house vs sweetness

Post by JB vintage »

How does the Taylor-Fonseca group compare to SFE in terms of sweetness?
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Re: house vs sweetness

Post by JB vintage »

jdaw1 wrote:
Glenn E. wrote:Baume doesn't translate easily to g/l, so I can't really understand what Julian's table represents. Is 3.4 - 3.8 a wide range? Is it sweet? It means nothing to me.
[url=http://theportforum.com/viewtopic.php?p=56602#p56602]Here[/url] jdaw1 wrote:Baumé on x axis, total acidity on y, for those 2011 Vintage Ports for which data available, and some others.
Image

Please let me know of other data that can be added.
My chart is from data published by the port houses. What, if anything, that data means ahh, a different question, but not one to ask me.
Niepoort is noticeably more acidic according to the table. Sweetness is mainly decided by the wine maker, but what about acidity? What parameter is the major determinant for acidity? Is it ripeness of the grapes? or grape variety? or what? Is acidity linked with house style or more with vintage and time of harvest?
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Re: house vs sweetness

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JB vintage wrote: Niepoort is noticeably more acidic according to the table.
more acidic in terms of "grams per litre" - but what i've never been able to get my head around is what that actually means (are all acids that occur in wine equally strong/concentrated?)
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Re: house vs sweetness

Post by djewesbury »

RAYC wrote:
JB vintage wrote: Niepoort is noticeably more acidic according to the table.
more acidic in terms of "grams per litre" - but what i've never been able to get my head around is what that actually means (are all acids that occur in wine equally strong/concentrated?)
I don't know that this translates into the subjective experience of 'acidity' as we describe it. More of a technical term, an oenologist's measure that then helps produces certain effects?
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Re: house vs sweetness

Post by RAYC »

djewesbury wrote:
RAYC wrote:
JB vintage wrote: Niepoort is noticeably more acidic according to the table.
more acidic in terms of "grams per litre" - but what i've never been able to get my head around is what that actually means (are all acids that occur in wine equally strong/concentrated?)
I don't know that this translates into the subjective experience of 'acidity' as we describe it. More of a technical term, an oenologist's measure that then helps produces certain effects?
I think my point was that it does not seem a particularly "technical" way of describing acidity in wine - for instance, i would have thought that pH level is an equally important part of the equation as the measure of total acidity in terms of assessing a wine's "acidity".
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Re: house vs sweetness

Post by djewesbury »

RAYC wrote:
djewesbury wrote:
RAYC wrote:
JB vintage wrote: Niepoort is noticeably more acidic according to the table.
more acidic in terms of "grams per litre" - but what i've never been able to get my head around is what that actually means (are all acids that occur in wine equally strong/concentrated?)
I don't know that this translates into the subjective experience of 'acidity' as we describe it. More of a technical term, an oenologist's measure that then helps produces certain effects?
I think my point was that it does not seem a particularly "technical" way of describing acidity in wine - for instance, i would have thought that pH level is an equally important part of the equation to total acidity.
Sorry, yes, I see what you mean. Perhaps one to ask Charles Symington tomorrow night?
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Re: house vs sweetness

Post by Glenn E. »

Isn't "acidity" in wine generally a measure of the tartaric acid content?

So while it isn't precisely a pH measurement, it's probably related.
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Re: house vs sweetness

Post by g-man »

yea

the main three are tartaric, malic and lactic.

tartaric is that "freshness" you get

malic is that "sour apple" flavor

lactic is that "creamy" flavor like in milk.

and technical way of describing should be the g/l of tartaric acid and the pH

that chart that julian produced is measurement of tartaric acid. It is important fo rthe stability of wine. too low and you'll have mold/bacteria growing in the wine producing off flavors.
it is also manipulated by adding tartaric acids directly into the wine to bring it up to a desired level.
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Re: house vs sweetness

Post by JB vintage »

I checked with Taylor and they replied that the Fladgate 2011 ports has the following sweetness
I have spoken to our laboratory and these are the results for the wines g/litre

Croft 101g per litre
Taylor 102g per litre
Fonseca 104g per litre
Not the same unit though as SFE so not fully comparable. Not very wide range though, is it?
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Re: house vs sweetness

Post by Alex Bridgeman »

I think that to answer these questions we need to compare wines with similar levels of acidity but different levels of Baume. Graham 1970 and 1977 look suitable candidates.

Could do something similar with Niepoort Bioma and Smith Woodhouse '11 to look at the effect of different levels of acidity.
Top Ports in 2024: Niepoort 1900 Colheita, b.1971. A near perfect Port.

2025: Quevedo 1972 Colheita, b.2024. Just as good as Niepoort 1900!
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Re: house vs sweetness

Post by g-man »

AHB wrote:I think that to answer these questions we need to compare wines with similar levels of acidity but different levels of Baume. Graham 1970 and 1977 look suitable candidates.

Could do something similar with Niepoort Bioma and Smith Woodhouse '11 to look at the effect of different levels of acidity.
interesting question and one i would love a winemaker to chime in on

but i dont think acidity and baume have any correlation at all.
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Re: house vs sweetness

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Just looking at the technical information on the Niepoort spec sheets, they list:

- both residual sugar (G/DM3) and Baume

- Both PH and Total Acidity (G/DM3)

- Separate measures for volatile acidity and Free SO2 (both (G/DM3))

One day, it would be good to get an explanation of how it all works (and eg: the balance of natural acids v acids added in the wine-making process, how they manipulate PH levels, other "interventions" etc.)
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house vs sweetness

Post by djewesbury »

RAYC wrote:Just looking at the technical information on the Niepoort spec sheets, they list:

- both residual sugar (G/DM3) and Baume

- Both PH and Total Acidity (G/DM3)

- Separate measures for volatile acidity and Free SO2 (both (G/DM3))

One day, it would be good to get an explanation of how it all works (and eg: the balance of natural acids v acids added in the wine-making process, how they manipulate PH levels, other "interventions" etc.)
I don't think sulphur dioxide content has any relationship to VA / acetic acid, does it? The others I agree with you about.

EDIT: My understanding is that SO2 is always added in the same proportion. I could be wrong.
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Re: house vs sweetness

Post by RAYC »

djewesbury wrote:
RAYC wrote:Just looking at the technical information on the Niepoort spec sheets, they list:

- both residual sugar (G/DM3) and Baume

- Both PH and Total Acidity (G/DM3)

- Separate measures for volatile acidity and Free SO2 (both (G/DM3))

One day, it would be good to get an explanation of how it all works (and eg: the balance of natural acids v acids added in the wine-making process, how they manipulate PH levels, other "interventions" etc.)
I don't think sulphur dioxide content has any relationship to VA / acetic acid, does it? The others I agree with you about.

EDIT: My understanding is that SO2 is always added in the same proportion. I could be wrong.
Isn't it what turns rain into acid rain? That's what i seem to remember being taught at prep school as we looked at eroded Gargoyles.
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Re: house vs sweetness

Post by RAYC »

djewesbury wrote:
RAYC wrote:Just looking at the technical information on the Niepoort spec sheets, they list:

- both residual sugar (G/DM3) and Baume

- Both PH and Total Acidity (G/DM3)

- Separate measures for volatile acidity and Free SO2 (both (G/DM3))

One day, it would be good to get an explanation of how it all works (and eg: the balance of natural acids v acids added in the wine-making process, how they manipulate PH levels, other "interventions" etc.)
I don't think sulphur dioxide content has any relationship to VA / acetic acid, does it? The others I agree with you about.

EDIT: My understanding is that SO2 is always added in the same proportion. I could be wrong.
Same proportion to what? Presumably not volume (2011 Bioma vs 2011 "regular" VPs are listed differently, and 2005 Colheita is listed at less than half the amount as VPs).
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Re: house vs sweetness

Post by djewesbury »

RAYC wrote:
djewesbury wrote:
RAYC wrote:Just looking at the technical information on the Niepoort spec sheets, they list:

- both residual sugar (G/DM3) and Baume

- Both PH and Total Acidity (G/DM3)

- Separate measures for volatile acidity and Free SO2 (both (G/DM3))

One day, it would be good to get an explanation of how it all works (and eg: the balance of natural acids v acids added in the wine-making process, how they manipulate PH levels, other "interventions" etc.)
I don't think sulphur dioxide content has any relationship to VA / acetic acid, does it? The others I agree with you about.

EDIT: My understanding is that SO2 is always added in the same proportion. I could be wrong.
Isn't it what turns rain into acid rain? That's what i seem to remember being taught at prep school as we looked at eroded Gargoyles.
Now that we do have to find out about! Can we ask a Gargoyle?
I remember Nick Delaforce telling a student how much SO2 to add to the must in the lagar (so many grams per litre) - and seeing the same quantity written on a post-it note on the winery wall at another quinta, as well as reading it in a book somewhere. If this is indeed a constant, then other factors would have to account for its unexpected transformation into VA.
RAYC wrote:Same proportion to what? Presumably not volume (2011 Bioma vs 2011 "regular" VPs are listed differently, and 2005 Colheita is listed at less than half the amount as VPs).
That's the amount of Free SO2 though, the amount that remains in the finished wine and is not transformed into other compounds, not the amount that is added in the first place.
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Re: house vs sweetness

Post by djewesbury »

I am on shaky ground here though. My last chemistry result was a D, and I've only really encountered SO2 in the form of campden tablets. Let's wait until we can ask a winemaker.
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Re: house vs sweetness

Post by g-man »

djewesbury wrote:
RAYC wrote:
djewesbury wrote:
RAYC wrote:Just looking at the technical information on the Niepoort spec sheets, they list:

- both residual sugar (G/DM3) and Baume

- Both PH and Total Acidity (G/DM3)

- Separate measures for volatile acidity and Free SO2 (both (G/DM3))

One day, it would be good to get an explanation of how it all works (and eg: the balance of natural acids v acids added in the wine-making process, how they manipulate PH levels, other "interventions" etc.)
I don't think sulphur dioxide content has any relationship to VA / acetic acid, does it? The others I agree with you about.

EDIT: My understanding is that SO2 is always added in the same proportion. I could be wrong.
Isn't it what turns rain into acid rain? That's what i seem to remember being taught at prep school as we looked at eroded Gargoyles.
Now that we do have to find out about! Can we ask a Gargoyle?
I remember Nick Delaforce telling a student how much SO2 to add to the must in the lagar (so many grams per litre) - and seeing the same quantity written on a post-it note on the winery wall at another quinta, as well as reading it in a book somewhere. If this is indeed a constant, then other factors would have to account for its unexpected transformation into VA.
RAYC wrote:Same proportion to what? Presumably not volume (2011 Bioma vs 2011 "regular" VPs are listed differently, and 2005 Colheita is listed at less than half the amount as VPs).
That's the amount of Free SO2 though, the amount that remains in the finished wine and is not transformed into other compounds, not the amount that is added in the first place.
this is NOT a constant

my understanding is that the VA fault is attributed to the vinegar bacteria. So it'd be Acetic acid. the sulfur is a preservative (much like in foods) to prevent other bacteria / mold from forming
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Re: house vs sweetness

Post by g-man »

RAYC wrote:Just looking at the technical information on the Niepoort spec sheets, they list:

- both residual sugar (G/DM3) and Baume

- Both PH and Total Acidity (G/DM3)

- Separate measures for volatile acidity and Free SO2 (both (G/DM3))

One day, it would be good to get an explanation of how it all works (and eg: the balance of natural acids v acids added in the wine-making process, how they manipulate PH levels, other "interventions" etc.)
it's a fun topic.

So, here's the assumption

Baume = relative density vs water
What attributes to making a liquid more dense then water?
Sugar
Alcohol
Organic compounds- Phenols, tannins, stuff

now because all ports have to be from 19.5-20.5 ABV.
the assumption is that the majority of the density calculation is pretty much the residual sugar.

So using baume you could make a rough guess on how much comparable RS is left in the comparison bottles.
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Re: house vs sweetness

Post by djewesbury »

g-man wrote:my understanding is that the VA fault is attributed to the vinegar bacteria. So it'd be Acetic acid. the sulfur is a preservative (much like in foods) to prevent other bacteria / mold from forming
Yes, exactly.
Acid rain = sulphur dioxide + nitrogen oxide + water.
VA = acetic acid = vinegar.
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Re: house vs sweetness

Post by g-man »

I dont think there's any sort of sulfuric acid in the food we eat .

https://www.courses.psu.edu/fd_sc/fd_sc ... eserve.htm
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Re: house vs sweetness

Post by JB vintage »

my understanding is that the VA fault is attributed to the vinegar bacteria. So it'd be Acetic acid. the sulfur is a preservative (much like in foods) to prevent other bacteria / mold from forming
This is exactly to my understanding. (too much) Volatile acidity is a fault in wine making mainly caused by the vinegar bacteria, perhaps caused by unclean barrels. Sulfur is added as a preservative (and for some other benefits) and might actually counteract any bacterial activity forming VA, and has nothing to do with converting to VA. Rather the opposite. In addition, there is no Sulfur present in the VA molecules as far as I understand. Sulfur does cause acid rain by forming sulfuric acid though. In the Niepoort example total acidity is counted in g/dm3 (5.06) and free so2 in mg/dm3 (80). As 1 gram is 1000 milligram the effect of any sulfur partly converting to sulfuric acid, H2SO4, is probably negligible as for affecting the overall acid content.
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Re: house vs sweetness

Post by oscar quevedo »

Interesting thread, Port geeks getting into Port chemicals.

My view which is quite similar with yours:
- baume is strictly related with density and sugar, as Jeff pointed; there is no correlation between baume and acidity
- the acidity that you can find in wine (not the added during fermentation or afterwards) is related with the ripeness of the grapes and the variety itself: Sousão has plenty of acidity while Tinta Francisca or bar steward very little; also depends when you harvest it, the earlier higher the acidity but get more of the green flavours and taste, less ripened fruit.
- VA is somehow related with sulphites as higher sulphites prevent VA bacteria to develop and multiply;
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