Dilution is the Solution Michael Moyer, M.S.

High Ethanol is a Problem Yeast die and don’t complete fermentation Yeast die and don’t complete fermentation Problem exacerbated at lower pH values(?) Problem exacerbated at lower pH values(?) Residual sugar can rapidly be converted to VA Residual sugar can rapidly be converted to VA Wine sensory effects: “hot,” unbalanced wines Wine sensory effects: “hot,” unbalanced wines Taxes: federal tax over 14.0% is 10¢ more per bottle Taxes: federal tax over 14.0% is 10¢ more per bottle Smaller volume of wine consumed! Smaller volume of wine consumed! Wine writer backlash against high alcohol wines? Wine writer backlash against high alcohol wines?

“High Alcohol is a Wine Fault… Not a Badge of Honor” Title of post by writer Matt Citriglia on winegeeks.com, May 14, 2006

Picking Decisions Of course we pick for flavor pH affects microbial stability and perceived sourness TA affects sourness and is an indicator of grape ripeness Brix correlates directly with wine alcohol concentration

“The most important piece of information I need to begin fermentation is what the sugar concentration is so I can get the addition of water in there and get the thing dry.” --- Barry Gnekow as quoted in the February 2009 issue of the Wine Business Monthly

How Not to Make Vinegar Take Brix measurement as soon as the juice is pressed or the must is in the tank Take Brix measurement as soon as the juice is pressed or the must is in the tank If possible, mix the tank to homogenize If possible, mix the tank to homogenize Use a refractometer (assuming fermentation hasn’t begun) Use a refractometer (assuming fermentation hasn’t begun) most automatically correct for temperature most automatically correct for temperature hydrometers can be quite imprecise and do not automatically correct for temperature hydrometers can be quite imprecise and do not automatically correct for temperature our densitometer does not automatically correct for temperature either our densitometer does not automatically correct for temperature either Re-measure red musts the next day (temperature?) Re-measure red musts the next day (temperature?) Brix can increase overnight Brix can increase overnight Dessicated berries? Zinfandel/Primitivo? Dessicated berries? Zinfandel/Primitivo?

The Most Important Analytical Tool

Sugar and Ethanol Conversion of sugar to ethanol and carbon dioxide is 90 to 95% efficient Conversion of sugar to ethanol and carbon dioxide is 90 to 95% efficient Myth: wild yeast strains are less efficient than cultured yeast strains Myth: wild yeast strains are less efficient than cultured yeast strains This has not been demonstrated and has more to do with marketing than anything else (Wine writers!) This has not been demonstrated and has more to do with marketing than anything else (Wine writers!) Cultured yeast strains have been selected for ethanol tolerance, not efficiency Cultured yeast strains have been selected for ethanol tolerance, not efficiency Final Ethanol % = 0.6 x ˚Brix Final Ethanol % = 0.6 x ˚Brix 0.6 conversion factor may be slightly lower for reds and may be slightly higher for white wines 0.6 conversion factor may be slightly lower for reds and may be slightly higher for white wines

2008 College Cellars Vintage Data 2008 Starting Brix Final Ethanol % Conversion Factor BC Semillon Center Cab Sauv SC Cabernet Franc Kagels Sangiovese Lowden Hills Syrah SC Cabernet Sauv SC Malbec Gibbs Cabernet Franc JW Lemberger

2007 College Cellars Vintage Data 2007 Starting Brix Ethanol % Conversion Factor SM Sauvignon Blanc Estate Merlot Estate Malbec Sagemoor Semillon Estate Carmenere

2006 College Cellars Vintage Data 2006 Starting Brix Final Ethanol Conversion Factor Sagemoor Semillon Estate Merlot Estate Malbec Frol Syrah Estate Demo Alder Ridge

Examples Hypothetical red must: Hypothetical red must: 26.0˚ x 0.6 = 15.6% 26.0˚ x 0.58 = 15.1% Hypothetical white: Hypothetical white: 23.0˚ x 0.60 = 13.8% 23.0˚ x 0.62 = 14.3%

Water Additions 101 Assume 160 gallons of juice per ton Assume 160 gallons of juice per ton Choose your desired ethanol concentration Choose your desired ethanol concentration (<15.0% for reds, <13.5% for whites) Divide desired ethanol concentration by the conversion factor of 0.6, + or – Divide desired ethanol concentration by the conversion factor of 0.6, + or – How careful do you want to be? How careful do you want to be? Volume juice x (Brix have/Brix needed) = Volume needed

Example: 5.0 tons at 27.0˚ Brix. For 15.0% ethanol: 15.0%/0.60 = 25.0˚ Brix For 15.0% ethanol: 15.0%/0.60 = 25.0˚ Brix Volume of juice = 5.0 tons x 160 gallons/ton = 800 gallons Volume of juice = 5.0 tons x 160 gallons/ton = 800 gallons Volume needed = (27.0/25.0) x 800 gallons = 864 gallons Volume needed = (27.0/25.0) x 800 gallons = 864 gallons Volume of water = 864 – 800 gallons Volume of water = 864 – 800 gallons = 64 gallons of water

Saignée and a Water Addition Sure, why not? Sure, why not? But do you want to make a rosé, especially from 27.0˚Brix juice? But do you want to make a rosé, especially from 27.0˚Brix juice? 27.0˚Brix x 0.62 conversion factor = 16.7% ethanol 27.0˚Brix x 0.62 conversion factor = 16.7% ethanol Be sure to add a bunch of water! Be sure to add a bunch of water! Or, dump 25 cases of potential product down the drain?! Or, dump 25 cases of potential product down the drain?!

Dilution? Sugars, yes. Sugars, yes. But this is what we want! But this is what we want! Acids, yes they are diluted. Acids, yes they are diluted. No problem, acidify the water with tartaric. No problem, acidify the water with tartaric. A rise in pH, not so much. A rise in pH, not so much. Wine is buffered and will resist a change in pH Wine is buffered and will resist a change in pH [TA measurements?] [TA measurements?] Tannins and anthocyanins? Not so much either Tannins and anthocyanins? Not so much either Add tannins, oak chips, if you wish, but not necessarily because you are adding water. Add tannins, oak chips, if you wish, but not necessarily because you are adding water.

Take Home Message Do your job! Finishing the alcoholic fermentation is the winemakers primary responsibility. Do your job! Finishing the alcoholic fermentation is the winemakers primary responsibility. Take extreme care to obtain and accurate initial Brix reading. It is the most important measurement you take. Take extreme care to obtain and accurate initial Brix reading. It is the most important measurement you take. Is dilution a solution? YES! Add enough (acidified?) water to finish fermentation. Is dilution a solution? YES! Add enough (acidified?) water to finish fermentation.