Though the grapes have been maturing slowly, the fruit hanging on the vines has almost completely turned red during the process called véraison. In other posts I’ve used the term véraison quite a bit and briefly explained its meaning but didn’t go into much detail. It is a borrowed French word meaning “the onset of ripening” and in English it is defined as the “change in the color of the grape berries”. Up until this point in the life cycle of the vine they have been expending their energy dividing and expanding the cells which form the grapes. The reddening of the grapes mark the moment that growth stops and ripening begins. The green turns to the familiar red hue of the grapes as chlorophyll breaks down and new pigment molecules such as anthocyanins are formed.

The acidity in the grapes begins to decrease as sugar accumulates. You may be familiar with the measurement Brix which is the percentage of sugar in the juice. Each week, the grapes will gain about 1.5ºBrix until they are fully ripened, usually at around 25ºBrix. Depending on the varietal, the winemaker may choose to harvest the fruit well before they become this sweet. Brix may rise further due to dehydration of the berry with no further sugar being produced.

This year I’ve really enjoyed watching the vines transform from little more than twigs into great leafy hedges. I’ve been eating the grapes throughout the growing season even when they were so sour they made my face pucker. It wasn’t until véraison occurred that they started to actually taste like grapes. The vines have a finite amount of energy available to produce the fruit. The trick is to channel that energy into producing high-quality, fully-ripened berries.

You hear the phrase “dropping fruit” a lot this time of year. It means removing clusters of grapes so that each vine has fewer bunches with the aim of producing more flavorful grapes. This is definitely something that distinguishes the wine industry from other agricultural industries: Growers get paid by yield, like every other farmer, but many are dedicated to quality and are willing to reduce yield to increase quality. At this point some of the clusters are lagging behind – while most of the bunches have reached 100% véraison, a few stragglers still have half of their green berries left. These bunches will never fully ripen and in the meantime just sap the energy out of the vine that could be used to ripen the other grapes. These green bunches will be cut off and sacrificed to help ripen the rest.

The crew is busy cleaning the winery in preparation for the incoming fruit but the harvest is so late this year that it’s likely they will finish well before the first grapes arrive. We’ll be using this downtime to send the crew into the vineyard to drop under ripe bunches and remove any grapes that raisined due to sun burn during the heat wave last week. Usually the grapes laid bare to the sun have a chance to tan, thus protecting them from sunburn. This year they never tanned. It was too cold. When the heat wave hit and temperatures got up to 105º these exposed berries got burned. Most of these bunches will be culled along with the green bunches.



Harvest has certainly been slow to arrive this year but soon the grapes will show up on the crush pad and begin their transformative journey. Part of what makes Deerfield wine so good is that we only use ingredients of the highest quality. So the first step is to sort the fruit - only perfectly ripe grapes make the cut. By the time the grapes arrive on the crush pad they have already been sorted once. In the vineyard, grapes that are fully ripe are the only ones that make it in the basket. But picking is huge job and workers, who often get paid per picking basket, don't always operate with as much scrutiny as we would like. For that reason once the grapes reach the winery they are sorted two more times by our crew.

The fruit is dumped from the half-ton bins that the grapes arrive in into a hopper which dumps them onto a conveyer belt and spreads the grapes out. At this point the grapes are still attached to their stems so we call this portion bunch sorting. We remove any leaves and clusters that are underripe or raisined. Sorters keep a constant vigil for any bunches that have any sign of mold or mildew. As the endless sea of grapes drift past, your eyes dart rapidly from bunch to bunch. Sometimes the signs of under ripeness are barely perceivable: The skins are a slightly different shade of red. Sometimes the only way to be sure is to taste them.

By the time the bunches of grapes reach the end of the sorting table and drop into the destemmer, only fully ripe grapes remain. The destemmer is a fairly simple machine. Paddles spin one direction and a cylinder with holes for the berries to fall through spins the other way. It's effectiveness varies, usually by the varietal. Zinfandel with its thick stems, for example, sometimes comes through the destemmer with no sign of any green at all. Just beautiful black pearls come out the other end. On the other hand Merlot's delicate stems often get chopped up and ejected along with the grapes.

The grapes then fall from the destemmer onto a "shaking table" which just a table with a grate that oscillates. It does an exemplary job of catching stems leaves and "shot berries" (tiny green grapes which were never pollinated). The shaking table was the bane of last harvest because it made a terrible racket. It was so loud that you couldn't hear the music that your headphones were playing. Halfway through harvest, Robert overheard a cellar rat grumbling about it and 30 minutes later, using only a wrench, silenced the machine.

The shaking table dumps the grapes onto a final sorting table. At this point the goal is to remove the MOG - industry slang for "matter/material other than grapes". If the yeast doesn't encounter any toxins during fermentation, the yeast will not need to produce histamines to protect themselves. Histamines are what cause red wine headaches. That is what we mean by clean wine and why Deerfield triple sorts our fruit, which is definitely not the industry standard. Mostly the focus is to remove anything green. The tiny stems that make it through the destemmer are often referred to as "jacks" because they look like jacks from the popular children's game of the same name. At the end of this sorting table all that remains is perfect, delicious grapes. We're anxiously awaiting the arrival of the first grapes! Harvest continues next week on DeerfieldCellarRat.com.

Last week we talked about how the grapes are sorted once they arrive on the crush pad. So what comes next? The sorted grapes are ready to be fermented at this point. We use two types of containers to ferment the fruit in, large stainless steel tanks and smaller plastic bins. Red wine goes through primary fermentation with the grape skins, which is where the vine gets its color. In fact, you can actually make a white wine from a red grape if the juice is immediately separated from the skins. Much of the tannin that gives red wine its structure is found in the skins so it is very important that the fermenting juice, or must, is in contact with the skins.

The skins float though, so they constantly rise to the surface forming a thick layer we call the cap. In order for the skins to fully transfer the flavor to the must, they must be re-submerged periodically, usually several times a day for the full duration of fermentation. This process is called a punchdown. You may have seen pictures of people on top of vats of grapes, holding themselves up while using their feet to push the skins down. Well we don't use our feet anymore but I guess the name stuck because the tool you use to punchdown the cap is called a foot. They come in many sizes and shapes but are usually just a rod with a flat surface with holes in it at one end. We've got several varieties of them here at Deerfield and I think everyone has their favorite one.

During crush we often have as many as 40 lots of wine fermenting at one time. Our protocol calls for each of these lots being punched down twice a day. So usually while the majority of the crew sorts fruit, one lone cellar rat goes from bin to bin punching down the skins. By the time you get done with the last one it is usually time to go back to the first one and start again. It's quite a work out. Sometimes it's as easy as pie but occasionally the cap is compacted and more than a foot thick. Perched precariously on the thin lip of the bin, wearing slippery galoshes, you throw your full weight onto the foot. Suddenly the cap gives way and you feel all resistance disappear. Falling into the delicate fermenting fruit is not an option so desperately you lean backward to regain your balance. Phew! Repeat another 40 times. The cap of the large stainless steel tanks is often too thick to punch down by hand so we use an alternate method which we call a pump-over that I'll go over next week.

The alternative to the punchdown technique I discussed last week is what we call the pumpover. If the cap is too thick to punchdown by hand or the winemaker thinks that the fermenting wine needs to be more thoroughly mixed, we use this method. We have a large hydraulic “foot” that attaches to our forklift that we can use to punchdown the large stainless steel tanks but for the most part we perform pumpovers on the tanks.

A cylindrical stainless steel strainer is inserted through the cap at the top of the container. This can be really difficult sometimes if the skins are too compacted. As soon as the strainer breaks through, the juice comes bubbling up to the top. Then one end of a hose is inserted into the strainer, which is long enough so that the hose can reach the liquid well below the cap. Using one of our powerful compressed air pumps we pump the juice over the top of the cap evenly for about 15 minutes – hence the name. This way the skins stay wet and the must at the bottom of the vat is able to come in contact with the skins. This adds enough oxygen to the must for the yeast to survive, stay happy, and do their job. Occasionally the juice gets sucked out of one area and the strainer needs to be moved around.

Pumpovers are much easier to do than punchdowns. The downside is that the pump must be cleaned between each pumpover. The foot that is used for punchdowns is easy to rinse and spray down with alcohol. But the pump must be taken apart, the remaining wine drained out of the machine and the hoses, then added back to the tank (only about half gallon, but it adds up after several weeks). Then the pump is reassembled and a proxy solution is circulated through it, then a citric acid solution and finally water. Once again it must be taken apart, and the hoses drained. Finally it is reassembled for use on the next tank. After doing this about a hundred times you get very fast at it but it still can take longer to clean the pump than it does to actually use it!

Personally I like doing pumpovers better than doing punchdowns just because the risk of falling in the bin and ruining the wine is stressful. So far we’ve covered sorting the fruit and one aspect of the primary fermentation process. The journey continues next week on DeerfieldCellarRat.com!



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 1/4^th 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!