When analying freshly crushed grapes, even after I strain the juice, I find a
significant difference between the Brix levels reasured by a refractometer and
when measured by a hydrometer. I suspect that it is due to suspended solids,
but which should I go by?

The refractometer measures 22.2 and the hydrometer measures 23.5 on a red must,
with a SG of 1.095.

On a white, the refractometer measures 18.5 and the hydrometer measures 22,
with a SG of 1.088.

The problem is that if I go by the refractometer reading on the white, I should
add some sugar.

Any suggestions? I hate to add sugar unless I have to.

Lee

"LG1111" wrote:

When analying freshly crushed grapes, even after I strain the juice, I
find a
significant difference between the Brix levels reasured by a refractometer
and
when measured by a hydrometer. I suspect that it is due to suspended
solids,
but which should I go by?

The refractometer measures 22.2 and the hydrometer measures 23.5 on a red
must,
with a SG of 1.095.

On a white, the refractometer measures 18.5 and the hydrometer measures
22,
with a SG of 1.088.

The problem is that if I go by the refractometer reading on the white, I
should
add some sugar.

Any suggestions? I hate to add sugar unless I have to.

First, make sure that the refractometer is calibrated for the temperature of
your must, and/or adjust the reading for the temperature. Most wine
hydrometers are calibrated at 59ºF. There should be a table that came with
the hydrometer that tells the amount to add or subtract for different
temperatures. If not, tables for brix and sg adjustments were posted
recently.

Second, make up a 20º Brix solution (weigh 20 grams of sugar into a
measuring cup, add water to 100 ml, and stir well). Test the Brix of the
solution with both methods. Decide which is the more accurate, and use it.

When analying freshly crushed grapes, even after I strain the juice, I
find a
significant difference between the Brix levels reasured by a refractometer
and
when measured by a hydrometer. I suspect that it is due to suspended
solids,
but which should I go by?

The refractometer measures 22.2 and the hydrometer measures 23.5 on a red
must,
with a SG of 1.095.

On a white, the refractometer measures 18.5 and the hydrometer measures
22,
with a SG of 1.088.

The problem is that if I go by the refractometer reading on the white, I
should
add some sugar.

Any suggestions? I hate to add sugar unless I have to.

Lee

Do you clarify the juice before taking a reading, Lee? I find this makes
for a more accurate reading with a hydrometer (usually reads slightly lower,
by a degree or so, before clarification)


clyde

"Clyde Gill" wrote:

Do you clarify the juice before taking a reading, Lee? I find this makes
for a more accurate reading with a hydrometer (usually reads slightly
lower,
by a degree or so, before clarification)

Clarification?

"Negodki" wrote in message
...
"LG1111" wrote:

When analying freshly crushed grapes, even after I strain the juice, I
find a
significant difference between the Brix levels reasured by a
refractometer
and
when measured by a hydrometer. I suspect that it is due to suspended
solids,
but which should I go by?

The refractometer measures 22.2 and the hydrometer measures 23.5 on a
red
must,
with a SG of 1.095.

On a white, the refractometer measures 18.5 and the hydrometer measures
22,
with a SG of 1.088.

The problem is that if I go by the refractometer reading on the white, I
should
add some sugar.

Any suggestions? I hate to add sugar unless I have to.

First, make sure that the refractometer is calibrated for the temperature
of
your must, and/or adjust the reading for the temperature. Most wine
hydrometers are calibrated at 59ºF. There should be a table that came with
the hydrometer that tells the amount to add or subtract for different
temperatures. If not, tables for brix and sg adjustments were posted
recently.

Second, make up a 20º Brix solution (weigh 20 grams of sugar into a
measuring cup, add water to 100 ml, and stir well). Test the Brix of the
solution with both methods. Decide which is the more accurate, and use it.

Brix is defined as grams of sugar per 100 GRAMS of liquid. A 20 Brix
solution can be easily made by adding 20 grams of sucrose to 80 milliliters
of water. See Ough "Winemaking Basics," page 260.
lum

"Negodki" wrote in message ...
"Clyde Gill" wrote:

Do you clarify the juice before taking a reading, Lee? I find this makes
for a more accurate reading with a hydrometer (usually reads slightly
lower,
by a degree or so, before clarification)

Clarification?

In theory filtering or clarifying juice by straining it is supposed to
give you a more accurate reading by removing suspended grape solids. I
have used a strainer and coffee filter and tried measuring both ways.
If there is a difference, it is less than a percent or two. If you
have a set of laboratory grade hydrometers, each set calibrated for a
specific gravity range so you can get more accurate readings, I bet
this would make a difference, as the theory certainly is sound. But if
you are suing the same $5 hydrometer that most of us have been using
since we got our first equipment years ago, then the difference most
likely will not be noticeable.

Regards,

Deadend

Clarification?

In theory filtering or clarifying juice by straining it is supposed to
give you a more accurate reading by removing suspended grape solids. I
have used a strainer and coffee filter and tried measuring both ways.
If there is a difference, it is less than a percent or two.

I find it can be off by as much as 4% ( 1 Brix out of 23) and I clarify the
juice by allowing the solids to settle out.... usually overnight.

clyde

"Negodki" wrote:

Second, make up a 20º Brix solution (weigh 20 grams of sugar into a
measuring cup, add water to 100 ml, and stir well).

"Lum" wrote:

Brix is defined as grams of sugar per 100 GRAMS of liquid. A 20 Brix
solution can be easily made by adding 20 grams of sucrose to 80
milliliters
of water. See Ough "Winemaking Basics," page 260.

I said, "Weigh 20 grams of sugar INTO a measuring cup, [then] add water TO
100 ml". This is the standard laboratory method of making a solution of any
particularly (percentage) strength (although with very small percentages one
makes a stronger solution in this fashion, and then dilutes to achieve the
desired percentage).

Since 20 grams of sugar in solution will only displace 12.9 ml (at standard
temperature and pressure), you need to add 87.1 ml of water to achieve a 10%
solution. This is precisely what the laboratory method does. Your method
would yield 92.9 ml of 21.5 % solution!

I discussed this in a recent thread. The value of 0.645 ml per gram of sugar
is from The American Wine Society's book, and appears in many other sources.
The laboratory procedure is from my college texts, and appears in thousands
of other sources.

"Negodki" wrote in message
...
"Negodki" wrote:

Second, make up a 20º Brix solution (weigh 20 grams of sugar into a
measuring cup, add water to 100 ml, and stir well).

"Lum" wrote:

Brix is defined as grams of sugar per 100 GRAMS of liquid. A 20 Brix
solution can be easily made by adding 20 grams of sucrose to 80
milliliters
of water. See Ough "Winemaking Basics," page 260.

I said, "Weigh 20 grams of sugar INTO a measuring cup, [then] add water TO
100 ml". This is the standard laboratory method of making a solution of
any
particularly (percentage) strength (although with very small percentages
one
makes a stronger solution in this fashion, and then dilutes to achieve the
desired percentage).

Since 20 grams of sugar in solution will only displace 12.9 ml (at
standard
temperature and pressure), you need to add 87.1 ml of water to achieve a
10%
solution. This is precisely what the laboratory method does. Your method
would yield 92.9 ml of 21.5 % solution!

I discussed this in a recent thread. The value of 0.645 ml per gram of
sugar
is from The American Wine Society's book, and appears in many other
sources.
The laboratory procedure is from my college texts, and appears in
thousands
of other sources.

I stand by the method I posted and by the reference I quoted. Try it.
lum

"Clyde Gill" wrote:
Do you clarify the juice before taking a reading, Lee? I find this makes
for a more accurate reading with a hydrometer (usually reads slightly
lower, by a degree or so, before clarification)

"Negodki" wrote:
Clarification?

"Deadend" wrote:
In theory filtering or clarifying juice by straining it is supposed to
give you a more accurate reading by removing suspended grape solids. I
have used a strainer and coffee filter and tried measuring both ways.
If there is a difference, it is less than a percent or two. If you
have a set of laboratory grade hydrometers, each set calibrated for a
specific gravity range so you can get more accurate readings, I bet
this would make a difference, as the theory certainly is sound. But if
you are suing the same $5 hydrometer that most of us have been using
since we got our first equipment years ago, then the difference most
likely will not be noticeable.

Ah, thank you. I do strain my must before taking measurements. The term
"clarification" threw me, as I associate it with a long process including
cold-stabilization and aging. I couldn't figure out how to do this to the
sample in the time frame for making sugar adjustments.

Lum wrote: "Brix is defined as grams of sugar per 100 GRAMS of liquid. A
20 Brix solution can be easily made by adding 20 grams of sucrose to 80
milliliters of water."

Negodki wrote "I said, Weigh 20 grams of sugar INTO a measuring cup, [then]
add water TO
100 ml". This is the standard laboratory method of making a solution of
any
particularly (percentage) strength (although with very small percentages
one
makes a stronger solution in this fashion, and then dilutes to achieve the
desired percentage).

Brix is a weight to weight term...grams of sugar in grams of solution. To
make a proper 20 brix solution you must weight 20 grams of sugar and
dissolve in enough water so the final solution weighs 100 grams. Lums
dilution probably is quite close to actual 20 brix and for our winemaking
work is probably close enough. Negodiki's solution is a weight to volume
solution and will be off a bit...but again, probably close enough for
amateur winemaking.

Bill Frazier
Olathe, Kansas

"Negodki" wrote:
Second, make up a 20º Brix solution (weigh 20 grams of sugar into a
measuring cup, add water to 100 ml, and stir well).

"Lum" wrote:
Brix is defined as grams of sugar per 100 GRAMS of liquid. A 20 Brix
solution can be easily made by adding 20 grams of sucrose to 80
milliliters of water. See Ough "Winemaking Basics," page 260.

"Negodki" wrote in message
I said, "Weigh 20 grams of sugar INTO a measuring cup, [then] add water TO
100 ml". This is the standard laboratory method of making a solution of
any particularly (percentage) strength (although with very small
percentages
one makes a stronger solution in this fashion, and then dilutes to
achieve the
desired percentage).

Since 20 grams of sugar in solution will only displace 12.9 ml (at
standard temperature and pressure), you need to add 87.1 ml of water to
achieve
a 10% solution. This is precisely what the laboratory method does. Your
method
would yield 92.9 ml of 21.5 % solution!

I discussed this in a recent thread. The value of 0.645 ml per gram of
sugar is from The American Wine Society's book, and appears in many other
sources. The laboratory procedure is from my college texts, and appears in
thousands of other sources.

"Lum" wrote:
I stand by the method I posted and by the reference I quoted. Try it.

Here are a few links which discuss both the correct procedure and the volume
of sugar in solution.

http://home.att.net/~jeffrey.d.mathi...de/percent.htm

http://www.hometrainingtools.com/art...ching-tip.html

http://www.coscosci.com/lab/test_solns.htm

http://www.uoregon.edu/~ch111/L21.htm

http://www.fao.org/docrep/V5030E/V5030E0f.htm

http://www.chem.uidaho.edu/~bitterte/molar.html

20 grams of sugar do NOT displace 20 millilitres of water, as your formula
requires. If they did, adding sugar would not change the specific gravity of
the solution! For the correct result, you must either compute the volume of
water to be added to the 100 ml solution as V=100 ml - (20 grams sugar *
..645 ml /gram); or you must place the 20 gms of sugar in a graduated
cylinder, and add water until a level of 100 ml is reached. Your formula
_would_ work for combining two liquid volumes.

As also discussed in the other thread, the difference between 80 and 92 ml
is probably smaller than the combined inaccuracy of one's measuring cups,
scale, and procedure. But, I think it best to shoot for the correct result
anyway.

I just noticed your statement "Brix is defined as grams of sugar per 100
GRAMS of liquid", emphasizing GRAMS. This is only true because the reference
liquid is water, and 1 gram of water displaces 1 milliliter of volume --- by
definition (this is the basis of the entire metric system, and all our
formulae). You don't really think the "Brix" of 1 gram of sugar in 100 grams
of alcohol or mercury would be the same as it is in 100 grams of water?

More mistakes have been made due to typos, misprints and incomplete
explanations than any other cause.

"William Frazier" wrote:

Brix is a weight to weight term...grams of sugar in grams of solution. To
make a proper 20 brix solution you must weight 20 grams of sugar and
dissolve in enough water so the final solution weighs 100 grams. Lum's
dilution probably is quite close to actual 20 brix and for our winemaking
work is probably close enough. Negodiki's solution is a weight to volume
solution and will be off a bit...but again, probably close enough for
amateur winemaking.

Il n'y a pas d'ennemi à droit (I surrender)!

If Brix is indeed a "weight to weight" term, then Lum is correct and I am
incorrect. Since 1 ml of water (at STP) weighs one gram, one can measure the
volume of water rather than weighing it. The variation from STP (standard
temperature and pressure) is insignificant in this instance.

I apologize to Lum for arguing, and to the rest of you for confusing the
issue.

Opps. I missed this thread; apologies.

I have a standard reference on this subject; Polarimetry,
Saccharimetry and the Sugars by Bates, published by NBS (NIST) in
1944.

Here is the definition of 20 Brix from it:

21.606 grams of sucrose (table or beet sugar are 99 % sucrose; it's
close enough).

107.991 grams of solute (the quantity of sucrose above + distilled
water to this weight).


equals (at 20C)

20.0 brix
or 1.083 S.G.

(The liter is defined as 1000 cubic centimeters of pure water at a
specific temperature, this method ignores volume measurements and
sticks to weight, (mass actually) of both water and sucrose.)

I have a spreadsheet on all of this I can post, but it's probably huge
for this venue. (I corrected it for the changes in definition of mass
in air since published, not that it's significant here.)

Just email me and I can send it to all who are interested, or I'll
post if desired. I wrote a hydrometer calibration procedure that
refers to it too, but I wanted to test it out prior to posting and
have not got to it yet.
Regards,
Joe




"Negodki" wrote in message ...
"William Frazier" wrote:

Brix is a weight to weight term...grams of sugar in grams of solution. To
make a proper 20 brix solution you must weight 20 grams of sugar and
dissolve in enough water so the final solution weighs 100 grams. Lum's
dilution probably is quite close to actual 20 brix and for our winemaking
work is probably close enough. Negodiki's solution is a weight to volume
solution and will be off a bit...but again, probably close enough for
amateur winemaking.

Il n'y a pas d'ennemi à droit (I surrender)!

If Brix is indeed a "weight to weight" term, then Lum is correct and I am
incorrect. Since 1 ml of water (at STP) weighs one gram, one can measure the
volume of water rather than weighing it. The variation from STP (standard
temperature and pressure) is insignificant in this instance.

I apologize to Lum for arguing, and to the rest of you for confusing the
issue.

"Negodki" wrote in message

I just noticed your statement "Brix is defined as grams of sugar per 100
GRAMS of liquid", emphasizing GRAMS. This is only true because the
reference
liquid is water, and 1 gram of water displaces 1 milliliter of volume ---
by
definition (this is the basis of the entire metric system, and all our
formulae). You don't really think the "Brix" of 1 gram of sugar in 100
grams
of alcohol or mercury would be the same as it is in 100 grams of water?

OK. I got it. But how many Brix let produce how much alcohol?
Grams or by volume?
Ri