MONO-MERCAPTAN/DI-MERCAPTAN TREATMENT*

(Always do small trials first before treating the rest of your wine!)

STEP #1- Test for and raise your SO2 level to the recommended amount,

relative to your pH.

If MLF is still incomplete, also add Lysozyme® to kill the M-L bugs.

STEP #2- Treat for Di-Mercaptans:

(3.75 mls of 1% Ascorbic Acid/gallon = 10 ppm)

	Slightly Stinky try 30 ppm. 1% Ascorbic	Mildly Stinky try 60 ppm. 1% Ascorbic	Very Stinky try 90 ppm. 1% Ascorbic or more
1 gallon	11.25 ml.	22.50 ml.	33.75 ml.
5 gallon	56.25 ml.	112.50 ml.	168.75 ml.
15.5 gallon	174.37 ml.	348.74 ml.	523.11 ml.
60 gallon	675.00 ml.	1,350.00 ml.	2,025.00 ml.

· Ascorbic makes di-mercaptans become mono-mercaptans.

· Wait 3-7 days and then do the mono-mercaptan treatment.

· Un-removed di-mercaptans will create more mono-mercaptans, and visa-versa.

· Note: ascorbic additions will confuse SO2 tests by the same number of ppms. This effect dissipates with time.

STEP #3- Treat for Mono-Mercaptans:

(.15 mls of 1% Copper Sulfate solution/gallon = .1 ppm copper)

	Slightly Stinky try .30 ppm. 1% Copper	Mildly Stinky Try .60 ppm. 1% Copper	Very Stinky Try .90 ppm. or more 1% Copper
1 gallon	.45 ml.	.90 ml.	1.35 ml.
5 gallon	2.25 ml.	4.50 ml.	6.75 ml.
15.5 gallon	6.97 ml.	13.94 ml.	20.91 ml.
60 gallon	27.00 ml.	54.00 ml.	81.00 ml.

· The copper will combine with equal amounts of sulfides/mono-mercaptans.

· .2 ppm un-bound copper is the legal limit. Too much can be toxic and can cause a metallic taste and a distinct haze. So, do not over-treat, but do treat enough to completely remove the offending odors/flavors.

· Un-removed mono-mercaptans will create more di-mercaptans, and visa-versa.

STEP #4- Add De-odorizing Carbon (Norit D-10):

(.02 oz to .08 oz. per 5 gallons) (That’s ¼ tsp. to 1 tsp. per 5 gallons)

	Slightly Stinky	Mildly Stinky	Very Stinky
5 gallon	.02 oz.	.05 oz.	.08 oz
15.5 gallon	.06 oz.	.15 oz.	.24 oz.
60 gallon	.24 oz.	.60 oz.	.96 oz.

· Simply dissolve in water and mix, gently, throughout the wine. The carbon will settle out in a few days to weeks, often clinging to the sides of the container.

If, after the above treatments, any mercaptans (any odors other than pure fruit of the grape) persist, you will have to repeat the treatments.

So, treat for the stinkies aggressively and completely.

* If your local supplier doesn’t carry 1% Ascorbic Acid Solution, 1% Copper

Sulfate Solution, Norit D-10 De-Oderizing Carbon, and the Pipets to measure

accurately, call us for our “Mercaptan Treatment Kit” ($12.95).

AVOIDING H2S!

Because growers dust their grapes with sulfur to retard mildew conditions,

you can easily develop H2S/ Hydrogen Sulfide (a rotten eggy, sulfury, burnt matches,

off odor smelled at the start of fermentation) in your wines.

What is more usual is that stressed grapes, especially late season grapes, are nutrient deficient,

leading to H2S formation (smelled at mid - late fermentation). (See the “Nutrient Risk Chart”)

To avoid the formation of H2S/Mercaptans:

· Add “Go-firm®” to the yeast re-hydration water.

· Add ¼ of your Yeast Nutrient just prior to yeast inoculation.

Use “Super Food®-Plus” plus “DAP”. (See the “Nutrient Risk Chart”)

· Let white juice cold settle. Then rack and add ¼ of your

“Super Food®-Plus” plus “DAP” just prior to yeast inoculation.

· Add ¼ more your nutrient at a drop of ~4º Brix

· This is also the time to add the M-L addition. Add “Leucofood®” or “Malo-Start®” as additional nutrient for the M-L bugs.

· Add the balance of the “Super Food®-Plus” and “DAP” every day or every 4° brix drop, until 5º Brix. More nutrient is useless to the yeast after reaching 5º Brix.

· Do not aerate, after the end of fermentation, or you will create di-mercaptans!

· If H2S is smelled, at the end of sugar fermentation, rack, and treat for mono-mercaptans, using copper only. (Consult the chart)

· If off odors persist after doing the copper treatment, rack and treat for di-mercaptans, using ascorbic, copper, and carbon. (Consult the chart)

· You probably would have been better off, at the first off odors, to have done the complete di-mercaptan treatment. Ascorbic, copper, carbon.

MERCAPTANS: If your wine doesn’t smell/taste like 100% pure fruit of the grape, then you have Mercaptans. Any odor other than pure rotten eggs (H2S) can be assumed to be Mono-Mercaptans which will only progress to Di-Mercaptans when aerated. If you smell mercaptans, assume and treat for Di-Mercaptans, using ascorbic, copper, and carbon.

Inadequate removal of ALL mercaptans will result in the regeneration of more stinkies somewhere down the line. These off-odors are in a state of flux. Not treating for one will result in the evolvement of the others.

· “Just throwing copper at the stinkies is the worst mistake a winemaker can make” The Wine Lab, Napa Valley.

Treat early and treat thoroughly.