All in all, a most interesting harvest! El Nino left lots of moisture which promoted mildew. Many growers lost 30-40% of their crop to mildew. Those that neglected their spraying regimen and those with older trellis systems that prohibited air/sun penetration of the canopy were especially hard hit. There'll be a lot of re-thinking of trellis systems this coming year!

Then the lateness of the harvest: Grape were low in nutrient, compounded by low temperatures, promoting stuck ferments and incomplete M/Ls. And, the grapes often had very fragile skins, promoting volatile acidity build-up. Late, or excessive sulfur spraying for mildew protection promoted H2S and subsequent mercaptans formation. Sugars were low, requiring sugar additions. The pHs were often high due to the long hang time, requiring tartaric acid additions and cold cellaring to drop out the excessive acidity.

Fortunately, as Cellarmasters, we've had access to a lot of pre and post crush winemaking info via this newsletter and the classes taught by club members. Additionally, Post Crush Clinics 1 & 2 gave us a forum to spot problems before they became uncorrectable. (A big, big thank you to Cellarmasters Stevenson, Tobin, Culver, Lustig, Haslett, queen, Meler, and Donatoni for panelling these two clinics. Their time, experience and info were invaluable to us all!).

To recap some of the things learned:

NUTRIENT DEFICIENCY: As mentioned, the longer grapes hang, the less natural nutrient remains at crush time. Wild yeast, M/L bugs, and your yeast are extremely competitive for and dependent on a balanced diet to do their job. Nutrient supplementation is always recommended and is essential under stress conditions like this year.

D.A.P.: Di Ammonium Phosphate. A cheap, primary source of Nitrogen, essential for yeast growth. Add at crush.

SUPER-SUPER FOOD - D.A.P., Yeast Hulls, Viamix, Yeast extract, plus extra D.A.P. and Vitamix are all essential for cell growth, metabolism, and enzyme activity. (Yeast Hulls absorb toxic fatty acids. Yeast Extract is a rich source of free amino acids. Vitamix has panthothenic acid, thiamine and biotin.)

LEUCOFOOD - Primarily Yeast Extract and Vitamix and some secret stuff to make it more expensive. It is loved by all M/L buggies who are extremely nutrient dependent and who are not capable of using Nitrogen. Add the appropriate nutrient when making those 1-2% by volume starters when adding the buggies to the must. Yeast can't process nutrient after the fact, towards the end of ferment.

VOLATILE ACIDITY: Long hanging grape skins tend to become flaccid, soft and fragile. With transport, a lot will rupture, permitting spontaneious, wild ferment. Indigenous acetobacter then convert the slight amount of alcohol to acetic acid and its ester, ethyl acetate. This volatility has a distinct nail polish smell. Some blows off with ferment. Too much is offensive and can only be diluted with other wines to cover the odor. Prevention is the cure.

Pick and crush grapes as cold as possible. This inhibits spontaneous ferment.

Add SO2 to 50 ppm. check your charts for the correct amount.

Keep the SO@ mixed well so that it can inhibit yeast and kill spoilage bacteria. Keep the cap wet by punch down frequently, especially before the yeast kicks in.

COLD SOAKING/PRE-FERMENT MACERATION: Once again, this simple cap mgmt. regime gave spectacular results. Colors and varietal fruitiness became much more "focused". Even tannins were extracted by this non-alcohol, aqueous soaking. All in all, the goodies were removed from the skins without the need of a hot alcohol ferment. This was beneficial as the weather turned cool, inhibiting warm fermentation. Some of us chilled the grapes with ice baths or inserting frozen jugs.

Have the grape cold before crushing. It's nearly impossible to chill down warm grapes, but it's easy to keep cool grapes cold. With warm grapes, you might as well crush, sulfite and get on with your fermentation.

Sulfite to 50 ppm (check your charts) and mix thoroughly to inhibit spontaneous ferment and prevent bacterial spoilage.

Mascerate the cap a lot to extract flavor and to keep the SO2 well mixed. This aqueous manipulation seems to release softer tannins versus the harsher tannins that come out with a hot alcohol exposure.

Keep temperature at 40*F, if possible. Four days minimum.

Note that it will take longer to get ferment started. Keep the cap wet to prevent spoilage. You may, then, also need to warm up the room if you desire the warm, traditional ferment that promotes a more "vineous" character. Warmth (65*F+) will still be needed after ferment to get M/L to finish.

THE STINKIES: Residual elemental sulfur on the grapes and a lack of nutrient make a great combination for the formation of H2S, Hydrogen Sulfide. As we were all warned at the Pre-Crush Clinic, residual H2S (rotten eggs) easily forms Mono-mercaptans (garlicky) and then Di-Mercaptans (Asparagus/vegy). These are all other than the nice, fruity odors of the grape variety. They can be detected in the parts per billion and will regenerate unless completely removed. Fortunately, there is a "Mercaptan Correction Kid" at The Shop that, if used, eliminates these off-odors.

If detected right at the onset of ferment, residual sulfur spray is the culprit.

If detected toward the end of the ferment, low nutrient is the culprit. Add nutrient, although it would have been more efficient to have added nutrient at crush, especially this year.

If the smell is solely H2S, and the wine is still fermenting, rack off of the generating source, the sediment, and splash vigorously to volatize the stink. Rack and splash, every 12hrs, as more sediment forms.

If Mercaptans also are present, aeration will generate Di-Mercaptans, making things worse.

When treating for Mercaptans, always assume that you have Di-mercaptans, and treat for both.

Treat with more ascorbic/copper sulfate than you think you need. Any Mercaptans remaining will regenerate Di-mercaptans. Active yeast will digest out excess copper, so add a little sugar after adding copper sulfate.

Complete instructions come with the "Mercaptan Correction Kit".

Well, I've managed to touch on a few things that we all "re-learned" from this 1998 crush. Let's hear what happened to you that might be useful to the rest of us!

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