Re: must analysis

Clarification?

refractometer

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

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

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

milliliters

I said, "Weigh 20 grams of sugar INTO a measuring cup, [then] add water TO

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.

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. :)

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

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.

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

Here is the definition of 20 Brix from it:

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

equals (at 20C)

(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

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

You description in parentheses means it is 107.991 grams of _solution_, making it 86.385 g of _solute_.

Or, if the description in parentheses is wrong, it is 129.597 g of solution.

Get your terms right.

Compared to water at what temperature for your specific gravity?

No. In 1944, the liter was defined as the volume occupied by 1000 grams of water at maximum density. About 1000.028 cm³.

Today, a liter is 1000 cubic centimeters. Always. It has nothing whatsoever to do with water.

A liter of water today is 999.972 g at maximum density, less at any other temperature. It never makes it to 1000.000 g.

Probably not ever.

Gene Nygaard

Hmm -- we're talking about wine. If it's close enough and makes adequate alcohol, that's enough for me!

:)

Perhaps I should have said .......20 grams of sugar in 80 grams of water. In any event, the Brix scale is in percent, grams of sugar per 100 grams of solute. The units are (gram/gram). See....... Margalit "Concepts in Wine Chemistry," page 10 or...... Zoecklein "Wine Analysis and Production," page

1. lum

You are correct, and the way you expressed it originally us correct, and I am completely in error, and I already apologized to you in another post in this thread. :)

I thought Brix was % sugar by weight = grams / ml x 100, but I guess (if it was) we wouldn't call it Brix, but %sugar. :)

No apology is necessary Negodki. The newsgroup is for exchanging different ideas. lum

Joe, send me a copy and I'll put it up on the FAQ.

Anyone else have a related document, I'd be happy to do the same.

clyde

Not really related, but if anyone is interested, I have a spreadsheet and word template set I created that keeps track of batches, bottles, etc. I can send to anyone or put up for post somewhere....

email: dallyn_spam at yahoo dot com please respond in this NG so others can share your wisdom as well!