Napa Valley After the Fires

The LNU Fire Complex
Our little corner of the world made the national news for the wrong reason this summer: fire. In mid-August, California’s fire season started early when ocean-bound heat from inland met with the wet remnants of a tropical storm from Baja California. The result was lightning strikes all over the state that started so many fires our Department of Forestry, called CalFire for its main mission, didn’t even bother naming them. Instead they lumped them into “complexes,” such as our LNU Complex (LNU = Lake-Napa Unit). Our portion of the LNU Complex did get a name, the Hennessey Fire, named for a ridge above Lake Hennessey where the fire started. That ridge is to the east of Napa Valley, and the fire mostly burned to the east. It caused immense destruction but the area is lightly populated. Still, we know too many who lost their homes and livelihood.

A Primer on Smoke-Taint and its Analysis
Though that fire burned away from Napa Valley, its smoke still came our way. “Smoke taint” in wine has been an all too common occurrence in California since at least 2008. Australia has been coping with it for even longer, and is leading the way in research on the issue, though UC-Davis and researchers in Washington State are quickly catching up (and collaborating with each other and with Australian researchers). That said, the phenomenon is still mostly mysterious. We know that it is not, or at least not only, a surface problem. It is probably wise to wash ash and smoky residues off grapes before processing them for wine, but while that may help it will not solve the problem. We know that when grapevines are exposed to smoke, they actively take up malodorous compounds and translocate (that is, move) them to the grapes. Why they do that remains a mystery. When the nasty compounds get to the grapes, the berries glycosolate them, meaning that they attach a glucose (sugar) or similar “moiety” to the offensive compound. That renders the compound non-volatile, and therefore not detectable by taste or smell. The berries still hanging in vineyards as I write this taste amazing! The problem is that in the acid conditions of fermentation the glucose bond to the offensive compound is broken, making the compound volatile and therefore detectable again.

Good for you if you are still with me! I apologize for my vagueness. Why do I keep writing “compound” rather than naming the offensive agent(s)? Because we don’t know what they are. We know that levels of guaiacol, a small phenolic compound found in cloves, are elevated in smoke-tainted wines, and guaiacaol is easy to test for. So guaiacol and the closely related 4-methylguaiacol are part of the panel of compounds we search for when we try to determine whether our grapes have been impacted by smoke. But guaiacol itself does not smell like a stale ashtray, and many wines that are not affected by smoke taint have high levels of guaiacol (and 4-MG).

Disputes Among Laboratories about How to Test and What to Test for
On a geeky sidenote, there are a number of labs doing testing in berries and wines to determine the level of smoke taint. They each have different methods and the philosophies behind each are compelling. Should the lab just measure free (unglycosolated) compounds, or should it also induce hydrolysis to measure the bound (glycosolated) precursors that could lead to nasty smoke characters? What if the process of hydrolysis itself creates the markers for smoke taint (such as guaiacol and 4-MG) from non-smoke related precursors such as the tannins and pigments naturally present in all wine grapes, tainted or not? If you would like to know more about these debates, let me know and I’ll happily geek out with you and forward resources your way.

The short version of the story, though, is that at this point the tests are not a perfect predictor of whether a wine will turn out to be undrinkable.

The Aftermath of the LNU Complex Fires
The LNU Complex fires began on August 17, about mid-way through the harvest of white grapes in Napa Valley, and well before most grapes for red wines would have been harvested. Fires aside 2020 was shaping up to be a somewhat later than normal vintage. The early August heat that made the LNU fires so likely was the first big heat we had had all summer. The growing season had otherwise been quite moderate.

Although we often get such heat events in Napa Valley, for some reason Cabernet Sauvignon handled the August heat spike particularly poorly. The Cabernet vines in Oakville from which I make The Albatross Cabernet Sauvignon started crashing in late August. Since we typically pick those grapes in early- to mid-October, this was not good. Putting scarce water on the vines didn’t seem to help. They were simply shutting down. Driving out to assess the situation, I saw that the problem with Cabernet was widespread throughout the Valley, even in the famed To-Kalon vineyard at the foot of the hill where “my” grapes grow.

At Benessere, my day job, the Cabernet was also suffering, and we brought some into the winery earlier than ever before. But let’s back up a bit.

Test Results
The local lab in St. Helena was already slammed with berry, juice and wine tests for smoke taint. The test takes 2 days to get results, but there was such a backlog that results were taking 5 days, then 10, then 20, then longer to get results. Hard to base picking decisions on that. I learned of a lab in the Okanagan Valley in Canada, one of Canada’s premier winegrowing regions, that offered much quicker turnaround time. We took berry samples of the various blocks at Benessere and sent them off. Results arrived a few days later and they were promising.

At the same time, we started microfermentations: 2-gallon lots from each variety in our vineyard. The idea was that if the resulting wines showed off aromas we would know that the grapes were tainted and there was no point picking.

Based on the Canada lab results and our microfermentations, we felt pretty good about the harvest. In came the grapes.

Bad News—and Why Smoke Taint is Really Nasty
When the fermentations were just over half-way done, the ugly signs of smoke taint revealed themselves. One lot smelled like a stale ash tray. Another smelled okay, but left an awful feeling in the throat as if you had just taken a gulp from a coal tailings pond.

I get well meaning suggestions all the time for how to use our affected grapes. Make barbecue sauce! Make jelly (smoke jelly?)! Don’t barrels impart a smoky flavor—maybe you can save money on barrels this year! Thanks for all the suggestions and, yes, the barrels we bought this year will not be used until next year, so we will save money that way. But folks, this stuff is nasty. Don’t think “pleasant evening by the fire,” think “someone dropped a cigarette butt in this beer,” or “who lit a tire in the living room?” This is not a pleasant phenomenon.

The Time Factor
Acid hyrdolysis liberates most of the bound precursors during fermentation, so by the end of fermentation you should know if you have a problem, right? Well, it’s not that simple. Remember we still don’t know what we are dealing with. (Mostly) all of what we have is anecdotal evidence, and it is not encouraging. Wines that are fine today can be horrid 6 months from now. Wines that have been treated for smoke taint (see below) can revert to that horrible state months or years after treatment.

Then What? The Glass Fire
At Benessere we had already pulled the plug on the 2020 harvest when the Glass Fire spiraled out of control. This one started in the hills east of the Valley floor but on the Valley side. High winds spread embers like mad, and even though CalFire threw everything they could at it, including two bombers (dropping flame retardant) and a bevy of helicopters, which took water from Benessere’s pond along with many others, the fire was at 0% containment for several days. We evacuated the morning after the fire started in the dark of pre-dawn. Only it wasn’t so dark because flames burned right up to both shoulders of Highway 29. We saw power lines burning. Even the cable car wires at Sterling, which would otherwise have been invisible at that hour, were brightly ablaze.

It was terrifying, but in terms of winemaking it meant that everything was on hold. All UpValley roads were closed, and with good reason. The County issued Ag Passes for workers who needed to get by road blocks. Benessere was able to do what was needed to keep from losing the wines already in tank. Having evacuated on Monday, September 28, we were not allowed home until Monday, October 5. Now things are as normal as can be in a Valley that has witnessed so much destruction.

Treatment—Isn’t There Anything to Be Done?
No. There isn’t. Activated Carbon can work miracles, and it can remove smoke taint characteristics, at least in the short term. The problem is that carbon removes a great deal else besides. Maybe the wine doesn’t taste like Eau-de-Ashtray anymore, but what does it taste like? Not much. There are various proprietary reverse osmosis (RO) techniques, and more coming all the time. RO works by very specifically binding to known compounds and pulling them out of solution. That’s great if you know what the compound you need to remove is. Not so great if you don’t. It is with RO treatment in particular that the smoke taint characters are known to return in a treated wine. When you don’t know what you are dealing with, it is hard to deal with it. I guess that’s the moral of every horror movie out there.

What did PWR do?
Some good news first. We made a Viognier this year from a vineyard new to us, and we harvested well before the LNU fires started. White wines are generally less susceptible to taint, mostly because they spend so much less time in contact with the skins where the offensive compounds are stored. But this is a straight up winner.

We also made some Rosé this year. Those grapes were picked after the LNU fires but before the Glass Fire. Thanks to limited skin contact, it seems like the Rosé is fine.

We made a Syrah from a vineyard in the Petaluma Gap that we have been drooling over for years. The wine has completed fermentation and it smells and tastes great! Will smoke taint materialize over time? I sure hope not, but all I can do is hope.

Similar story with our Oakville Cabernet. Our fingers are crossed!

What You Can Do
If you have read this far, you are obviously concerned and I thank you for that. We—PWR, Beatrix and me—are fine. Many in our Valley are not. You can help financially by buying any wine produced in Napa Valley. For more specific help, you can donate to UpValley Family Centers and Community Action of Napa Valley. Both organizations are helping people who have lost their homes, their possessions, their jobs, and more.

Also, please vote. I can’t imagine that any of you are not already planning to participate in this election, but if somehow one of you is not, please reconsider. Fire is a natural phenomenon, but these fires are as much the result of human-induced climate change as they are anything else. For far too long we have been aware of the science of climate change and have hidden our heads at best, denied it at worst. That must change. And to paraphrase, the best time to do something about climate change is 30 years ago. The second best time is now.

Nutrition Facts — part 2 of the rant

There is a big push to add nutrition information to wine labels. It may surprise you to learn that some of the biggest wine producers are pushing the hardest to require such information on labels.

We are all for information, not to mention transparency. But that is not what this is about. This is about the compliance costs for smaller producers. The bigger producers can absorb those costs easily, and in fact, their label costs will barely budge due to economies of scale and other factors described in part one of this rant.

It is also frustrating that the information found on a nutrition facts label barely pertains to wine. Let’s take a look line by line.
Serving size. This will be interesting. Australia has a definition of “a drink” that is based on alcohol content. So some bottles might contain 4.5 servings while another might contain 8 servings. We’ll see what happens here.
Calories. Assuming the wine is dry, this will scarcely budge from wine to wine, and the influencing factor will be alcohol content. If serving size is determined by alcohol content, calories per serving won’t vary at all (but total calories per bottle will). Not very useful information.
Total Fat. Really? You think there is fat in wine? You will need more than a Nutrition Facts label to help you with that. Seriously, folks, no fat in wine. Got it?
Sodium. Rarely measured in wine now, and surely quite low. This is another way the bigs stick it to the smalls. The incremental cost of sodium analysis will hit small producers much harder than larger ones. Regardless, the number will be very low, under 10 mg/serving for most wines.
Total carbohydrate. This is a tricky one, as a dry wine contains no actual carbohydrates at all. So will all the labels say 0 or will they put in the grams of alcohol (not a true carbohydrate) per serving? This could be interesting for the big producers, too, as they seem much more inclined to leave residual sugar in their products without telling anyone. Once people see that their favorite supermarket wine has 1-3g of sugar per serving, will they stop buying it?
Protein. A laugh. Winegrapes don’t contain much protein. What is there is consumed by the yeast and left with their cells when the wine is racked off the lees. Further, the tannins in red wine bind with and precipitate any protein that might remain. White wines can contain a bit of protein, which is a big concern for winemakers. If that protein gets denatured, by heat for example, it can throw an ugly haze. For that reason most winemakers take steps to remove any protein from white wine before bottling, sometimes by adding tannin to interact with it as in red wines and sometimes by adding Bentonite, a clay that pulls the protein out of solution. That way, if your wine gets cooked in transit, you’ll never be the wiser! (Hey, is that how it should work?)
Vitamins. Nil.
Calcium. Negligible.
Iron. Negligible, or so the winemaker hopes!
Potassium. This will vary a lot. California wines are generally much higher in potassium than those from other regions. Does this matter to you?
Ingredients. The argument over whether to require–or even allow–ingredient listing is taking place separately from the nutrition facts argument, and we’ll look at that in another post.

In sum, if you think you want nutrition facts on a wine label, ask yourself why and what you hope to learn. Chances are you won’t find significant differences among wines. The requirement would impose burdensome costs on small producers and benefit consumers not in the least.

What do you think?

The struggles of small wineries – a tempered rant in two parts

by Matt

There are a number of reasons why small wineries have a harder time of it than larger ones. Most are just the nature of the business. But when the bigger wineries go out of their way to make it harder for us small guys, it gets my hackles up.

Economies of scale are one example of how size matters. When I order labels, the price I pay barely budges whether I buy 1000 pieces or 10000 pieces, so the price per label naturally drops rapidly the more you print. Imagine if your print runs ran to the millions….. Other supplies, too, get cheaper in quantity. Moreover, spending power can lead to further discounts as vendors don’t wish to see those funds go to a competitor. All of this is sensible, even if I don’t particularly like it.

Last year the California Alcoholic Beverage Control commission (ABC) started going after wineries that mentioned restaurants and retailers on their social media accounts. For example, “Restaurant X now has our wine by the glass. Go check it out!” This is a violation of California’s tied-house rules, which state that an alcohol producer cannot give anything of value to a customer other than the alcohol they explicitly purchase. Apparently ABC considers a tweet to have value (a dubious supposition). So many wineries got dinged over this that there was a backlash and the rules were changed somewhat. Producers are now able to tweet about upcoming events at restaurants and retailers as long as they stick to facts (e.g., the date of the event) and not opinions (e.g., the food is great!).

When ABC was asked about the social media crackdown, they explained that they had received complaints and that they have to act upon all complaints they receive. In other words, the crackdown was not the result of an ABC busybody but rather an anonymous tipster who had it in for the smaller brands who don’t have the legal teams and resources to fight back. An anonymous ABC source implied that it was a winery employee who had made all the complaints. I have my guesses about who, but just imagine what kind of winery has enough employees that they can assign one the task of scrolling through endless twitter feeds looking for violations of this obscure rule. That’s right, a big one.

This year it seems something more nefarious is afoot. Take a look at John Hinman’s story here.

Recently, a number of wineries received one-day license suspensions for allegedly allowing consignment sales, which are not allowed under federal rules. Sitting out a day of business might have seemed easier to these small wineries than taking on the expense of contesting the charges. However, as Hinman’s piece explains, the accused may not have understood the consequences of pleading guilty to even a minor charge. Hinman’s law firm represents at least one of the accused, and Hinman makes a strong case that the sales in question were not in fact consignment sales and the charges could likely have been successfully fought.

What is more troubling to me, however, is the fact that TTB charged only small wineries with this violation, when many larger wineries also practice what TTB is calling consignment sales (though they may not be). What’s behind the TTB’s focus on small wineries? I don’t know, but I hope to find out.

I hope that was not too arcane for you. I would love to hear your thoughts. I’ll be back with another way the big wineries are sticking it to the small, and it may surprise you. Can you believe that a push to require nutritional labeling on wine bottles is actually a veiled effort to increase costs for small producers? Stay tuned…..

Grape Varieties — Prologue: Species, varieties, and clones

With grape varieties like Cabernet Sauvignon, Chardonnay, Sauvignon Blanc and Pinot Noir dominating the markets, the varieties we work with may be unfamiliar to you. Here we will introduce you to the varieties we work with: Viognier, Zinfandel, Petite Sirah, and, coming soon, Grenache. But first, a little background.

What is a grape variety?
With few exceptions, most wine is made from a single species of grapevine, Vitis vinifera L. Wines made from other fruits must so indicate on the label, e.g., blueberry wine, or dandelion wine. In some parts of the United States, winters are too severe for V. vinifera to survive, so other species of grape vine, most of which are indigenous to the US are used. Unfortunately, many of these species, such as V. labrusca (Concord), V. riparia, and Muscadinia Rotundifolia (Muscadine, Scuppernong) produce wines with flavors that many consider off-putting.

Varieties and clones
So, yes, everything from Albariño to Zinfandel–including Cabernet, Chardonnay, etc.–are the same species. The differences among them make each a variety. Note that a wine produced from grapes of single variety can be called (a) varietal. Even within a given variety, differences among grapevines can be detected. Some are minor, such as leaf size. Others can have a relatively large impact on the resulting wine. Pinot noir clone 777, for instance, is known to produce wines with deeper color and more intense tannins than other Pinot noir selections, or clones. Generally speaking, the older a variety, the more diversity its clones will show. Pinot noir and Sangiovese have tremendous diversity among clones, and both are thought to be at least 1000 years old. Cabernet Sauvignon, by contrast, likely resulted from a spontaneous cross between Cabernet franc and Sauvignon blanc in Bordeaux in the mid-18th century. Many Cabernet Sauvignon clones have distinctive characteristics, but not to the same extent as older varieties.

Next up: Viognier

 

Filtration Explored and Explained

In our recent piece on wine fining, we touched on filtration and promised a more thorough discussion of that topic. Here it is, at last. There are two principal reasons to filter wine, but some consumers are so afraid of filtration that many producers choose not to filter. We will do our best to present the facts and let you draw your own conclusions.

One reason to filter a wine is to improve its appearance. Allowing the wine to settle in barrel or tank is a great way to clarify it, but sometimes the spent yeast and other particles simply won’t settle to the bottom in the alloted time. Filtration can remove those particles and leave the wine limpid and bright. Another reason to filter is for microbial stability. No one wants to open a bottle and find it still fermenting, or nearly explosive with foul-smelling gases. A third type of filtration is performed by larger wineries only, to recover wine from the lees that settle to the bottom of the maturation vessel. This requires special equipment and enough lees to justify the investment, which most smaller producers just don’t have. We will ignore that here, but if you have questions about it, ask away.

Filtration tools and techniques—pad filtration

To understand how and why we might filter for appearance or for stability, it is helpful to understand how filtration works. There are two technologies in widespread use today. Pad filtration is the older technology. A series of cellulose (wood pulp, essentially paper) sheets are stacked in a frame and wine is forced through them. The tighter the weave of the cellulose, the more solids are left behind. One obvious disadvantage is that cellulose has flavor, and it is not a flavor that we would enjoy in our wine. This is easily overcome, however, by running (a lot of) water through the pads prior to introducing the wine. The water emerging from the pads is tasted and, when there is no more “papery” taste, it’s time for the wine. Another disadvantage is that the size of the gaps in the cellulose is imprecise. The filter sheets are sold with a nominal pore size, but there will always be a range of sizes. This can be of special concern when filtering for stability.

Typically a wine will go through several sets of pads, starting with bigger (looser) pores, and ending with tighter or smaller pores.

Crossflow filtration

A newer filtration technology is called crossflow because, rather than pushing the wine through the filter medium, it gradually passes through as it circulates. The filter medium is a membrane and it can have very precise pore sizes, making this a better choice for filtration for stability. Typically only one pass is needed, as opposed to one pass for each pore size as with pad filtration. Membrane filtration is also a necessary first step to treating a wine with reverse osmosis, which we will discuss below as a special application of crossflow filtration.

Filtration for appearance

To clean up or “polish” a wine, either technology will work. For pad filtration, the wine might first pass through pads with a nominal pore size of 5-7 microns (0.005-0.007mm) and then, if not “bright enough,” through another set of pads with 2-3 micron pores. Some winemakers who do this will still confidently claim that there wine has not been filtered, for reasons that elude us (but may be elucidated below).

Filtration for stability

Naturally, if the concern is to remove microbes, the pores have to be tighter. Wine is a wonderful beverage in that virtually no human pathogens can survive in it. Nevertheless, some microbes can survive in it and, while they pose no threat to human health, they can pose a threat to the taste of the wine. Lactobacillus spp., for instance, can metabolize any sugars left in the wine and produce acetic acid (vinegar smell) and carbon dioxide (gas, foaming). The acetic acid may form an ester with the ethanol in the wine to create ethyl acetate, which smells like nail polish remover. Brettanomyces yeast can use ethanol as fuel and transform polyphenol precursuors into nasty vinyl phenols that smell of anything from stale hay to horse manure. Not what we want to drink!

A 0.45 micron pore size is generally considered tight enough to remove bacteria (much larger yeast will have been removed at larger pore sizes). With pad filtration it usually takes 4 passes to filter to this level, but with crossflow filtration it can be achieved in one pass. Some winemakers prefer to go tighter still, to ensure that no bacterial spores can persist in the wine. 0.2 microns is considered safe for this. Again, the pore size for filter pads is nominal, and even at the tightest level there may be larger pores that could allow bad agents to pass, but at a minimum the filtration will dramatically reduce their population and thus the risk of contamination.

The downsides

Filtration sounds great, doesn’t it? So why are some consumers afraid of it, and why do some producers proudly claim they forego it? Much of the hostility towards filtration seems to be based in romantic ideas of a wine’s integrity, or even soul. Wine certainly inspires mystical thinking and that is part of its charm. But do odd bits of grape pulp and particles of dead yeast really comprise an integral part of the beverage? Dead yeast actually can contribute pleasant flavors and textures to a wine. That is properly the subject of another piece, but in brief, as the yeast cells die and autolyze, they release compounds into the wine that can enhance mouthfeel, making the wine feel more silky and rich on the palate. Still, that can and should happen before the wine goes into bottle. Leaving the spent yeast in the bottled wine just makes for a cloudy drink.

Another downside of filtration is the risk of oxidation. Anytime a wine is handled there is the chance for oxygen pickup. At best oxygen can make a wine seem prematurely “tired” or flat. Alcohol is oxidized to acetaldehyde, which smells like stale apples. The risk of oxidation is greater with pad than with crossflow filtration, not least because of the multiple passes required for pad filtration. With a skilled operator, however, the oxygen pickup is minimal.

Perhaps the biggest concern with filtration has to do with its affect on a wine’s structure. But this, we will see, is based on a misunderstanding. Many elements contribute to a wine’s structure, which is how it appears on the palate, or its “three-dimensionality.” Tannins give the wine its grip, and ethanol can make it seem somewhat thick, as can glycerol and any residual sugar.

Colloids also contribute to wine’s structure and mouthfeel. Colloids are associations of large molecules, and they cannot pass through a filter intact. Tasting a wine that has just passed through a filter can be a shock. The mouthfeel is completely changed, usually for the worse. We suspect it is this mistake—tasting just after filtration—that contributes most to filtration’s bad rap. However, the components of the colloids do pass through the filter, and with time they re-form the colloids. All better now.

Why we filter

We started filtration with the 2013 vintage. We have had no reports or complaints regarding the appearance or stability of our earlier, non-filtered wines, or for that matter, of our later, filtered wines. We decided to filter because we wanted to be sure that the wines you enjoy are as we intended them, with nothing nefarious happening before you open that bottle. We hope that this piece has helped you to understand our rational for filtering, and what the process entails. Please chime in with any comments or questions you have on the subject.

Post-script—reverse osmosis

Crossflow filtration can be so tight that it can discriminate among molecules by size. The principal components of wine: water, ethanol, and organic acids such as tartaric and malic acids, are all quite small by molecular weight. So are most volatile compounds, which contribute aromas. When bad things happen to good wines, unpleasant volatile compounds are often produced. Some examples are acetic acid and ethyl acetate, the volatile phenols mentioned above, and compounds related to “smoke taint,” such as 4-methylguaiacol. Wines can pass through a crossflow filter and then over resins that selectively bind these compounds. With the bad actors gone the treated path is reunited with what did not pass through the filter to re-create the now restored wine. This technique can also be used to adjust the alcohol content in the wine. The permeate (the portion that passed through the filter) is distilled to remove the alcohol before being rejoined with the retentate (the portion that did not pass through the filter). Pretty crazy stuff!

2017 Wildfires Update

Last night a gentle rain began to fall over Napa Valley. In Calistoga we got a welcome 0.36″ of precipitation. I cannot remember the last time rainfall was so welcome (which shows how quickly I forget the 5+ year drought that just ended).

When we returned to Calistoga from our evacuation on Monday, the valley was still ablaze. Our Cabernet vineyard in the hills above Oakville was surrounded on three sides by towers of flame. A trio of helicopters made endless loops scooping water from Robert Mondavi Vineyard (thank you!!!) and dumping the water on those burning hills just above.

I drove down-valley yesterday and the flames are completely extinguished, revealing burn scars on the hillsides. Thank you firefighters, first responders, and everyone who came to save our homes and livelihoods.

The fires began the night of Sunday, October 8. We held on until we faced mandatory evacuation on Wednesday, October 11. In the interim, the fires laid waste to much of Santa Rosa (our nearest big city), the eastern and western sides of the city of Napa, and so much more.

As we sat in exile, we could only hope that we would have a home–and a town–to return to. We are so grateful to all who made that hope a reality.

We are deeply aware of how fortunate we are, and of how much our friends and neighbors have lost. If you would like to help those in need, we recommend donating to the Napa Valley Community Foundation: https://latino-community-foundation.networkforgood.com/…/38…

For other reputable suggestions, please look here: http://www.sacbee.com/news/local/article177964926.html

Our community will take a lot of love to be made whole. Thank you for sharing yours.
Smoke filled the valley on Monday, October 9

Another smoky scene from Wednesday, October 11, the day we evacuated.

This picture does not convey how red the sun was through the smoke.