My main reference book for winemaking is Duncan & Acton's _Progressive
Winemaking_ (1967).

It says that the initial SG of a must should generally be below 1100,
and that feeding sugar syrup later is required for wines over 14% ABV.
It's recommendation for feeding is to add 4 ounces of sugar per gallon
(dissolved to make sugar syrup), when the SG is between 1000 and 1005,
to be repeated as required when the SG is back in that range.

But this book also says "most yeasts can produce at least 10%
alcohol", which sounds a bit out of date.

I'm using Gervin No.3, which is supposed to be fairly alcohol-tolerant
(up to 18%, I think) and suitable for dessert wines, to make a wine
based on Pomegreat (a pomegranate juice blend, which contains about
100 g/l of natural sugar).

I think the feeding rate of 4 oz per gallon at a time sounds rather
conservative. Are yeasts generally "tougher" than they were then?
What is the contemporary rule of thumb for this?

Thanks,
Adam


--
It is probable that television drama of high caliber and produced by
first-rate artists will materially raise the level of dramatic taste
of the nation. (David Sarnoff, CEO of RCA, 1939; in Stoll 1995)

On Jul 14, 3:27*pm, Adam Funk wrote:
My main reference book for winemaking is Duncan & Acton's _Progressive
Winemaking_ (1967).

It says that the initial SG of a must should generally be below 1100,
and that feeding sugar syrup later is required for wines over 14% ABV.
It's recommendation for feeding is to add 4 ounces of sugar per gallon
(dissolved to make sugar syrup), when the SG is between 1000 and 1005,
to be repeated as required when the SG is back in that range.

But this book also says "most yeasts can produce at least 10%
alcohol", which sounds a bit out of date. *

I'm using Gervin No.3, which is supposed to be fairly alcohol-tolerant
(up to 18%, I think) and suitable for dessert wines, to make a wine
based on Pomegreat (a pomegranate juice blend, which contains about
100 g/l of natural sugar).

I think the feeding rate of 4 oz per gallon at a time sounds rather
conservative. *Are yeasts generally "tougher" than they were then?
What is the contemporary rule of thumb for this?

Thanks,
Adam

--
It is probable that television drama of high caliber and produced by
first-rate artists will materially raise the level of dramatic taste
of the nation. * * *(David Sarnoff, CEO of RCA, 1939; in Stoll 1995)


If you are using a yeast strain to achieve a particular goal (i.e.
many yeasts can have an impact on flavour, acid levels, H2S risk,
etc), then it is more important to use the desired yeast and make sure
you don't kill it with sugar or alcohol.

Note that it is not only the eventual alcohol level that is the
problem, but the fact that too high a concentration of sugar in the
must can also be toxic to yeast. So, just because a yeast can handle
16% or more alcohol in the finished wine, doesn't mean that it can
handle the high-sugar environment of the initial must.

Now, it tends to be the case that high alcohol tolerance goes hand-in-
hand with sugar tolerance, but that is not always true. In the case
of Gervin No. 3, I'm pretty sure it is rated for up to 18% alcohol and
is also recommended for dessert wines (i.e. very high initial SG), so
you're good to go.

In general, you need to check the specs on the specific yeast you are
using, and think about what your goal is in using the yeast.

wrote:

On Jul 14, 3:27*pm, Adam Funk
wrote:
My main reference book for winemaking is Duncan
& Acton's _Progressive Winemaking_ (1967).

It says that the initial SG of a must should
generally be below 1100, and that feeding sugar
syrup later is required for wines over 14% ABV.
It's recommendation for feeding is to add 4
ounces of sugar per gallon (dissolved to make
sugar syrup), when the SG is between 1000 and
1005, to be repeated as required when the SG is
back in that range.

But this book also says "most yeasts can
produce at least 10% alcohol", which sounds a
bit out of date.

I'm using Gervin No.3, which is supposed to be
fairly alcohol-tolerant (up to 18%, I think)
and suitable for dessert wines, to make a wine
based on Pomegreat (a pomegranate juice blend,
which contains about 100 g/l of natural sugar).

I think the feeding rate of 4 oz per gallon at
a time sounds rather conservative. *Are yeasts
generally "tougher" than they were then? What
is the contemporary rule of thumb for this?

Thanks,
Adam

--
It is probable that television drama of high
caliber and produced by first-rate artists will
materially raise the level of dramatic taste of
the nation. * * *(David Sarnoff, CEO of RCA,
1939; in Stoll 1995)


If you are using a yeast strain to achieve a
particular goal (i.e. many yeasts can have an
impact on flavour, acid levels, H2S risk, etc),
then it is more important to use the desired
yeast and make sure you don't kill it with sugar
or alcohol.

Note that it is not only the eventual alcohol
level that is the problem, but the fact that too
high a concentration of sugar in the
must can also be toxic to yeast. So, just
because a yeast can handle 16% or more alcohol
in the finished wine, doesn't mean that it can
handle the high-sugar environment of the initial
must.

Now, it tends to be the case that high alcohol
tolerance goes hand-in-
hand with sugar tolerance, but that is not
always true. In the case of Gervin No. 3, I'm
pretty sure it is rated for up to 18% alcohol
and is also recommended for dessert wines (i.e.
very high initial SG), so you're good to go.

In general, you need to check the specs on the
specific yeast you are using, and think about
what your goal is in using the yeast.

It is also a good idea to check the specs on the
optimal temperature range for the specific yeast.
I learned this the hard way.

On 2008-07-15, Paul E. Lehmann wrote:

It is also a good idea to check the specs on the
optimal temperature range for the specific yeast.
I learned this the hard way.

I'll check on that too, thanks.


--
No right of private conversation was enumerated in the Constitution.
I don't suppose it occurred to anyone at the time that it could be
prevented. [Whitfield Diffie]

On 2008-07-15, wrote:

Note that it is not only the eventual alcohol level that is the
problem, but the fact that too high a concentration of sugar in the
must can also be toxic to yeast. So, just because a yeast can handle
16% or more alcohol in the finished wine, doesn't mean that it can
handle the high-sugar environment of the initial must.

Good point.

Now, it tends to be the case that high alcohol tolerance goes hand-in-
hand with sugar tolerance, but that is not always true. In the case
of Gervin No. 3, I'm pretty sure it is rated for up to 18% alcohol and
is also recommended for dessert wines (i.e. very high initial SG), so
you're good to go.

Not good to go with the whole amount of sugar at the start, though?

I'm planning to add another 500 g of corn sugar to the (approximate)
gallon (in addition to what was in the juice blend already and the
500 g I've already added). If I were following the book, I'd do that
in five stages, but should I risk doing it in one, or two?

(I suppose if it doesn't work and the fermentation sticks, I could go
back to the brewing shop to see if they have the yeast specifically
labelled as "high-alcohol" in stock.)


In general, you need to check the specs on the specific yeast you are
using, and think about what your goal is in using the yeast.

Right, but I can't find a Gervin website (see next post).


--
Nam Sibbyllam quidem Cumis ego ipse oculis meis vidi in ampulla
pendere, et cum illi pueri dicerent: beable beable beable; respondebat
illa: doidy doidy doidy. [plorkwort]

Not good to go with the whole amount of sugar at the start, though?

Well, it probably won't kill the yeast, but it might be a very slow,
sluggish fermentation. If you want the primary fermentation to be
done in a week to 10 days then you'll want to give the yeast a good
environment to really get going, then it'll be able to ferment the
sugar additions more quickly and efficiently.

Dessert wines often finish at over 200 g/L. Most Icewines are well
above this when they are bottled, but they take several weeks, even
months, to ferment from the starting brix of 40+.



Right, but I can't find a Gervin website (see next post).

I couldn't find one either, but I found some write-ups on brewing shop
websites and it seems to be recommended for high-alcohol and also for
re-starting stuck fermentations, so you probably have the right yeast
for what you are doing.

On 2008-07-18, wrote:

Not good to go with the whole amount of sugar at the start, though?

Well, it probably won't kill the yeast, but it might be a very slow,
sluggish fermentation. If you want the primary fermentation to be
done in a week to 10 days then you'll want to give the yeast a good
environment to really get going, then it'll be able to ferment the
sugar additions more quickly and efficiently.

OK. If the current SG isn't very high, I'll add another 500 g (over
about 4.5 litres) tonight.


Dessert wines often finish at over 200 g/L. Most Icewines are well
above this when they are bottled, but they take several weeks, even
months, to ferment from the starting brix of 40+.

Are you sure "200 g/L" is right? That's more than most beer worts
*before* fermentation!


Right, but I can't find a Gervin website (see next post).

I couldn't find one either, but I found some write-ups on brewing shop
websites and it seems to be recommended for high-alcohol and also for
re-starting stuck fermentations, so you probably have the right yeast
for what you are doing.

Thanks. (I've got a Gervin product leaflet, but it's at least 10
years old.)


--
NO CARRIER

Adam Funk wrote:
On 2008-07-18, wrote:

Not good to go with the whole amount of sugar at the start, though?
Well, it probably won't kill the yeast, but it might be a very slow,
sluggish fermentation. If you want the primary fermentation to be
done in a week to 10 days then you'll want to give the yeast a good
environment to really get going, then it'll be able to ferment the
sugar additions more quickly and efficiently.

OK. If the current SG isn't very high, I'll add another 500 g (over
about 4.5 litres) tonight.


Dessert wines often finish at over 200 g/L. Most Icewines are well
above this when they are bottled, but they take several weeks, even
months, to ferment from the starting brix of 40+.

Are you sure "200 g/L" is right? That's more than most beer worts
*before* fermentation!

Sure does sound high... I thought we're shooting for 1-4% residual
sugar, which would be 10-40 g/L if I'm not mistaken.


Right, but I can't find a Gervin website (see next post).
I couldn't find one either, but I found some write-ups on brewing shop
websites and it seems to be recommended for high-alcohol and also for
re-starting stuck fermentations, so you probably have the right yeast
for what you are doing.

Thanks. (I've got a Gervin product leaflet, but it's at least 10
years old.)

On 2008-07-19, gene wrote:

Adam Funk wrote:
On 2008-07-18, wrote:

Dessert wines often finish at over 200 g/L. Most Icewines are well
above this when they are bottled, but they take several weeks, even
months, to ferment from the starting brix of 40+.

Are you sure "200 g/L" is right? That's more than most beer worts
*before* fermentation!

Sure does sound high... I thought we're shooting for 1-4% residual
sugar, which would be 10-40 g/L if I'm not mistaken.

I found some a table of final gravity "targets" for various categories
in another old book (Mitchell, _Scientific Winemaking Made Easy_,
1969):

Dry white wine ferment to dryness
Dry red wine ferment to dryness
Sweet white table wine 1020
Medium sweet dessert wine 1010
Sweet dessert wine 1038

An original gravity of 1038 is 105 g/L, so a final gravity of 1038 is
going to have more sugar than that (because the alcohol lowers the
overall density), but not 200.

(Since I have rather more experience in homebrewing than winemaking, I
found the FG 1038 quite shocking at first.)


--
Any employee here on the hill would run at high speed: 9600 or 19200
baud. Only someone calling through a modem would let their data
dribble out of a 1200-baud soda straw. (Stoll 1989)

On 2008-07-19, Adam Funk wrote:

Not good to go with the whole amount of sugar at the start, though?

Well, it probably won't kill the yeast, but it might be a very slow,
sluggish fermentation. If you want the primary fermentation to be
done in a week to 10 days then you'll want to give the yeast a good
environment to really get going, then it'll be able to ferment the
sugar additions more quickly and efficiently.

OK. If the current SG isn't very high, I'll add another 500 g (over
about 4.5 litres) tonight.

Yesterday I forgot to measure before adding the sugar, but the sample
I took while syphoning had SG 995, so I think I had waited long
enough.

My big mistake with this batch was starting off with just the
Pomegreat in the demijohn and coming back to add all the sugar after
fermentation had started --- so I didn't have much room to add syrup
(I couldn't fit all the wine in after the second addition).


--
Leila: "I don't think he knows."
Agent Rogersz: "Increase the voltage."
Leila: "What if he's innocent?"
Agent Rogersz: "No one is innocent. Proceed" (Cox 1984)

On Jul 20, 11:57*am, Adam Funk wrote:
On 2008-07-19, gene wrote:
Adam Funk wrote:
On 2008-07-18, wrote:
Dessert wines often finish at over 200 g/L. *Most Icewines are well
above this when they are bottled, but they take several weeks, even
months, to ferment from the starting brix of 40+.

Are you sure "200 g/L" is right? *That's more than most beer worts
*before* fermentation!

Sure does sound high... *I thought we're shooting for 1-4% residual
sugar, which would be 10-40 g/L if I'm not mistaken.

I found some a table of final gravity "targets" for various categories
in another old book (Mitchell, _Scientific Winemaking Made Easy_,
1969):

* Dry white wine * * * * * * *ferment to dryness
* Dry red wine * * * * * * * *ferment to dryness
* Sweet white table wine * * *1020
* Medium sweet dessert wine * 1010
* Sweet dessert wine * * * * *1038

An original gravity of 1038 is 105 g/L, so a final gravity of 1038 is
going to have more sugar than that (because the alcohol lowers the
overall density), but not 200.

(Since I have rather more experience in homebrewing than winemaking, I
found the FG 1038 quite shocking at first.)

--
Any employee here on the hill would run at high speed: 9600 or 19200
baud. *Only someone calling through a modem would let their data
dribble out of a 1200-baud soda straw. *(Stoll 1989)

Go by taste and not by numbers, those are just very rough ballpark. In
fruit winemaking especially, the acids vary largely even for the same
type of fruit, so taste gives you a better chance of arriving at a
balanced product. That said, values around 1.040 are quire normal for
dessert wines, with icewines much higher as has been pointed out -
that's because the acid is so concentrated in icewine juice that very
high sugar levels are needed to bring it into balance... that word
again.

Pp

On Jul 20, 2:57*pm, Adam Funk wrote:
On 2008-07-19, gene wrote:
Adam Funk wrote:
On 2008-07-18, wrote:
Dessert wines often finish at over 200 g/L. *Most Icewines are well
above this when they are bottled, but they take several weeks, even
months, to ferment from the starting brix of 40+.

Are you sure "200 g/L" is right? *That's more than most beer worts
*before* fermentation!

Sure does sound high... *I thought we're shooting for 1-4% residual
sugar, which would be 10-40 g/L if I'm not mistaken.

I found some a table of final gravity "targets" for various categories
in another old book (Mitchell, _Scientific Winemaking Made Easy_,
1969):

* Dry white wine * * * * * * *ferment to dryness
* Dry red wine * * * * * * * *ferment to dryness
* Sweet white table wine * * *1020
* Medium sweet dessert wine * 1010
* Sweet dessert wine * * * * *1038

An original gravity of 1038 is 105 g/L, so a final gravity of 1038 is
going to have more sugar than that (because the alcohol lowers the
overall density), but not 200.

(Since I have rather more experience in homebrewing than winemaking, I
found the FG 1038 quite shocking at first.)


In Ontario, the MINIMUM allowable residual sugar in a finished icewine
is 125 g/L. 180 g/L to 220 g/L is not uncommon.

Botrytized wines can get even higher still--Sauternes has been known
to get over 400 g/L in the finished wine, and there have been Tokaj
wines as high as 900g/L RS.

On 2008-07-22, wrote:

An original gravity of 1038 is 105 g/L, so a final gravity of 1038 is
going to have more sugar than that (because the alcohol lowers the
overall density), but not 200.

(Since I have rather more experience in homebrewing than winemaking, I
found the FG 1038 quite shocking at first.)


In Ontario, the MINIMUM allowable residual sugar in a finished icewine
is 125 g/L. 180 g/L to 220 g/L is not uncommon.

Looking for info, I've just discovered that "Icewine is a rare gift
from a magical Canadian winter." Interesting.


Botrytized wines can get even higher still--Sauternes has been known
to get over 400 g/L in the finished wine, and there have been Tokaj
wines as high as 900g/L RS.

Wow. I had no idea.


--
() ascii ribbon campaign - against html e-mail
/\ www.asciiribbon.org - against proprietary attachments

On 2008-07-21, pp wrote:

Go by taste and not by numbers, those are just very rough ballpark. In
fruit winemaking especially, the acids vary largely even for the same
type of fruit, so taste gives you a better chance of arriving at a
balanced product. That said, values around 1.040 are quire normal for
dessert wines, with icewines much higher as has been pointed out -
that's because the acid is so concentrated in icewine juice that very
high sugar levels are needed to bring it into balance... that word
again.

Taste is important, but I also want to avoid unexpected bottle
fermentation. ;-)


--
Two of the most famous products of Berkeley are LSD and Unix.
I don't think that this is a coincidence. [anonymous]