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Dear Winemakers,
We are more than half way through the grape harvest and still think it is
summer! Initially, the most meaningful
parameter of grapes and grape juice to an aspiring amateur winemaker is Brix or
sugar percentage or degree. It is the one factor that connotes maturity. If the
sugar is high, it must be ripe. The higher the sugar the riper the fruit, the
more sugar the better. NOT NECESSARILY SO! Many winemakers never go beyond this
way of thinking. However, as the winemaker advances, he soon learns the
importance of acidity and pH.
pH is a dimension that expands the quality aspects of wine. It ties in with
acidity and places limitations on use of various additives that the winemaker
commonly uses. It is sometimes the reason a jug of wine goes down the drain,
when everything was done correctly. This is a simplified caution regarding
several products.
Product limitations: Wines with a higher pH will required more Bentonite and possibly
other fining agents for good fining results. Calcium carbonate, CaCO3, used to
reduce acid pre-fermentation at the rate .3-.4 grams /liter will increase the pH
by ~ 0.1. This shift must be taken into consideration and is the restriction in
the use of CaCO3 and the other acid reduction aids. The pH shift will vary
depending on the chemistry of the must. Must meaning the grape mess. If the
initial pH of the grape is below 2.95, the shift in the pH with the use of acid
reduction chemicals may not be an issue. Acidex also shifts the pH. Potassium
Bicarbonate neutralizes the acid and raises the pH of the wine even more than
calcium carbonate. This can be an advantage in dealing with problem varieties
with a pH below 3.0 and a TA above 1.0. Raising the pH of such wines will help
soften their acid taste. However, this can also be a major disadvantage or
limitation in its use. It is recommended only for use with wines with a pH below
3.0 and a T.A. above 1.0 to insure that the final pH will not exceed 3.5.
Maximum reduction of TA is in the .25 to .3% range to hopefully avoid an
increase in the pH that is not advantageous. With a higher pH a wine will also
require more potassium metabisulfite.
A final pH of 3.4 to 3.45 at the end of the winemaking process is acceptable. A
pH of 3.5 or 3.6 will not yield a long living wine. If your wine has strange
problems, check the pH. Keep tabs on the pH!
We have a portable pocket pH Meter for sale at the shop this year. It is a
Milwaukee 51 with Automatic Temperature Compensation 0-50 deg C. Highly accurate
manual 2-point calibration with a replaceable electrode part number MA73600. It
has 1500 hr continuous use battery life with an auto-shutoff after 10 minutes.
It is waterproof to 6 ft underwater. I don't know about six feet under wine.
Batteries: 3 x 1.5 V. Two-year warranty, padded case. This pH meter comes with
packets of buffer solution for calibration, plus a tiny screwdriver. I had Tom
use one so we could at least answer questions about it. The electrode needs to
soak in the buffer 4.01 solution for 12 hours before use. Tom also calibrated it
with the buffer 7.01 solution as he uses the pH meter for the end point of 8.2
during acid test. (The Phenolphalene color indicator in our TA kits has a
reaction point of 8.2. The indicator is a color change when you use the
indicator solution. Leave the indicator out, just use the Sodium Hydroxide and
titrate to 8.2.) Both calibrations are necessary if you use the pH meter for
your end point during TA test. The instructions did not indicate whether the
screw used for calibration adjustment of the 4.0 was on the right or left! With
the meter facing you, the adjustment screw (under the battery cap on top) for
the buffer the buffer 4 is on the right and the 7 calibration is on the left. We
are quite pleased with this little pH meter. We had one several years ago and
had to refund and return all of them. This Milwaukee 51 meter doesn't have any
of the problems we had with the other meter. It is an affordable item and will
help our winemakers tremendously!
Start out your winemaking using age old and new recommendations and you can make
award-winning wines! Need help? Call us at 607-292-3995. Check out our website, www.fallbright.com
for information and online shopping . Our shop staff make wine and can answer
your questions. Tom is our most advanced winemaker and we take your advance
winemaking problems to him. Now, during harvest, we are open Tuesday to Sunday,
10-5. May your wines fall bright. Tom and Marcy
If you want me to remove you from our mailing list, just reply and ask!
Thanks
Fall Bright, The Winemakers Shoppe
10110 Hyatt Hill
Dundee, NY 14837
607-292-3995
Tuesday -Sunday 10-5 EST
www.fallbright.com
winemaking@fallbright.com
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