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Slightly Cloudy With A Chance Of Mold

I would imagine that for most people the mere thought of wine evokes mental images of long vines and rolling hillsides covered with trellises. That's why I'm always perplexed at the disconnect it seems people have between the vineyard and the finished product. We don't at all view wine as a product in the same light that we see other agricultural products in the grocery store, like say... artichokes. Somewhere along the way the grape is transformed. It is fermented, studied, blended, bottled and lo! It becomes wine. And at that point, I feel, we cease to see it as an agricultural product. We hate to compare it to the likes of carrots and potatoes and arugula. That is what makes it easy to forget that wine really is a product of the land and that a crop of grapes is susceptible to all of the trials and tribulations that Mother Nature throws at it. In fact, the wine grape is far more imperiled by disease and weather than most crops. Vitis Vinifera is one of the toughest plants in the world in that it can grow in extremely poor soil and without much water at all, but it is especially vulnerable to pests, disease and molds. And when a farmer intends to make wine out of his grapes he can expect to grow more than a few grey hairs. To make a wine worth its yeast, the grapes that went into it must be harvested at optimal conditions: When the sugar is at the perfect concentration in each berry (known as brix). It's mostly up to Nature to decide when that will be, if at all...

And that is why this harvest, when the weather forecast came in for the end of October, we started to get many panicky growers showing up at the crush pad, asking with increasing melancholy when their fruit would be harvested. The person who is purchasing their grapes is the one who gets to decide when the harvest occurs but the fruit is weighed and paid for after it's been picked. So if the grapes get moldy due to rain, as was the case this harvest, and needs to be discarded, it comes out of the pocket of the grower and not the winemaker (if the two aren't the same party). So this can create a tenuous situation, as the winemaker is obviously more concerned with making the best wine possible, and the grower is concerned about selling the as much quality fruit as possible. The hope is that their interests will align. For most of the harvest this was certainly the case. But as the rain loomed towards November it seemed disaster might strike.

This harvest disaster struck. A cool early fall caused many of the varietals that ripen slowly like Cabernet to dawdle and then the monsoon that came at the end of October drenched all of the grapes still hanging on the vine. This made copious amounts of water available to their root systems. The resulting grape is the same as pouring some water into your glass of fine wine. Vines need to be stressed with only just enough water to perform their biological functions. That way the fruit they produce is concentrated in flavor and sugar. The only way to recover from the vines binge drinking is to wait for the ground to dry and the grapes to lose some of the water again. It's a dangerous game however, because a dense canopy of wet grape leaves provides the perfect environment for mold to grow. Almost all of the grapes we got after the rain were affected in some way by the mold. In a lot of places the winemaker would throw up their hands, exclaim "C'est la vie!", and throw the moldy grapes into the fermentation tank. But at Deerfield we rolled up our sleeves and sorted out every single moldy bunch. At our peak before the rain, the crew could sort about one ton of grapes an hour up to Deerfield's level of expectation. After the rain it took up to 4 hours to sort one half ton. For comparison, mass production wineries will sort up to 30 or 40 tons of grapes an hour. You'd be surprised: That type of production is by no means limited to the likes of Carlo Rossi, though I won't name names...

So harvest slowed way down and despite our best efforts, quality suffered slightly but I have full confidence in Robert's ability to save the day. After all, a lot can happen between harvest and the time it's ready to bottle. In the end, 2009 will be a mixed vintage for Northern California. We saw some truly spectacular fruit before the rain and some really terrible stuff afterwards. I hope the sour grapes don't tarnish the reputation of the whole vintage. Sometime I'll discuss how entire vintages can suffer from bad reputations and how that's unfair. Until next time!

Second Protocol

Thank you for indulging me last week in my aside - I hope I conveyed the feeling of winter here at the winery. I'll return now to my recap of the 2009 harvest.

Where we last left off the heavy and early fall rain had greatly complicated things, creating mold in the vineyard, and we were slowing down the sorting table to a crawl in a valiant effort to remove the affected fruit. But the sorting table wasn't the only front at which we were to battle the gray-green scourge. We would have to change our entire method of operation to combat our foe...

And so our winemaker put into effect a Second Protocol with which we were to handle all of the wines we were crafting. No matter how discerning we were at the sorting table it is impossible to completely remove all the mold as some of the pesky microbes aren't even visible to the naked eye. The wines would be later treated to remove all trace of the fungi but in the interim it was imperative that the clean wines we had fermenting already not be contaminated. During fermentation it is crucial not use equipment on different lots without sanitizing it in between, in order to prevent cross-contaminating the lots with different yeast strains. It only takes one little yeast cell to create an entire colony.  But there are many stages during production where it is not necessary to totally sterilize everything between working with different wines. After the Second Protocol was instituted those days were long gone. Everything had to sprayed with ozone between every time ANY piece of equipment touched a grape or juice. Ozone is used industrially as a disinfectant. It's useful because Deerfield has an ozone generator which creates it from the ambient air so you have an unlimited supply. Ozone is an O3 molecule whereas oxygen is O2. It's amazing how that one extra oxygen atom changes it from life giving to lethal. Ozone has incredible oxidizing power and as it decays back to the stable oxygen configuration is releases free radicals that can break the carbon bonds of organic molecules making it a deadly enemy of the unwanted spores invisibly infesting our hoses and pumps. The enemy of my enemy is my friend. But it's a double edged sword because since ozone is such a terrific oxidizing agent it must not come in contact with the wine either. So a spray with ozone and a thorough rinse before any work is done is prescribed but not expedient. I think I've mentioned before how much easier the process can be if you just cut a few corners. To follow the protocol to a T required dedication, patience and imagination: You have to imagine how much better the wine will taste if you take the time to do it right. And at Deerfield we do it right. Every time.

Fortunately, this all happened as the work at the winery was beginning to reach its zenith as the last of the grapes came in. As sorting stopped the attention of the crew could be shifted to the fermenting wines and our time was freed up a great deal. Next time I'll talk about the winding down of harvest and putting the wines to sleep so they can mature. Salut!

Grapes Don't Like Chilly Wet Mornings And Neither Do I

When I moved into my tent at the winery over a year ago I wondered why in the early morning I would hear what sounded like a fleet of helicopters landing in the vineyard. I now know that what I was hearing was the sound of vineyard owners battling the frost that threatened to destroy their grapes. If the temperature drops to below 32º F for more than 30 minutes there is a chance that ice crystals will form within the plants cells and destroy any green growth. During the spring when the buds are forming that will produce the fruit for harvest, the entire crop is vulnerable. In the fall early rains mixed with low temperatures can cause the grapes to shatter on the vine. Growers have developed a number of ways to combat this potentially disastrous scenario. Overhead sprinklers are one such technique. By covering the vines in water constantly the plant tissue will remain at 32º as long as the temperature is above 20º. The technique is effective but the systems are expensive, require maintenance and use about 55 gallons per acre per minute to be completely effective. That’s a lot of water. Heaters have also been used, though usually in conjunction with another method. Vineyard heaters for commercial use must comply with California emission standards but still can burn up to about a gallon of diesel fuel an hour per unit. Imagining the vast vineyards of California blanketed by these heaters makes the environmentalist in me cringe. The fans I mentioned earlier circulate the warmer air that is higher in the atmosphere. These can raise the temperature at the level of the grapes to 1/4th the difference between the temperature at 4 feet off the ground and 40 feet. So if there is a 4º temperature difference the fans will effectively raise the temperature at the height of the vines by 1º. The Department Of Agriculture’s Natural Resource Conservation Service is working with vineyards owners to switch to this method to conserve water. Maintaining soil that radiates heat effectively is an important component that can be utilized to bolster any frost protection strategy. Soil that is clean, firm and moist is best. Research recently done at the University of California, Berkeley indicates that the ice crystals that form in plant tissue must have a nucleus on which to form. Bacteria is what provides such a nucleus so by reducing the amount of ambient bacteria present on the vines the risk of frost should theoretically be reduced, though this strategy has yet to be implemented commercially. Frost damage is not a threat everywhere in California but in the Valley of the Moon where Deerfield Ranch Winery is located it is a threat that we contend with every year. We made it through spring without too much issue, though we did use our dual purpose irrigation system which makes use of water that is recycled by our on-site water treatment bioreactor. Usually, in Sonoma county, fall frosts which damage crops are rare because typically the fruit has been harvested. We can't seem to catch a break this year: A frost warning was issued for Wednesday morning. It looks like this time that the threat didn't materialize though. Deerfield is planning to pick its entire Syrah vineyard by mid next week. I'll let you know how it goes!