Well, our wine isn’t supernatural, that’s for sure 😊
It’s hard to say what “natural wine” is because there isn’t an agreed definition for the term the way there is for “organic” (set by the USDA) or “biodynamic” (set by Demeter, a private organization that owns the trademark for the term).
At its most “natural,” wine would be made by harvesting, crushing, and destemming grapes, and then leaving microorganisms to do the rest. It would taste pretty awful by the end of the process, after spoilage organisms and oxygen had their way with the wine.
To make the product taste better, most wine is made with human intervention along the way… and like most things, there is a spectrum of intervention. Mass-produced wines tend to be near the high end of the spectrum as interventions are used to streamline manufacturing, improve profit margin, or compensate for low-quality fruit. In contrast, premium winemakers are able to stay at the low end of that spectrum by sourcing high-quality fruit and creating the conditions that allow natural processes to work best. Even so, no wine is made with no human intervention at all.
What do we do at Resistance to make more-than-just-drinkable wine?
1. We inoculate our fermentations with yeast that we have selected
Yeast are everywhere – in the vineyard, in the winery, in your kitchen… Like breeds of dogs, different types of yeast vary in their characteristics and abilities. Would you hitch a team of Chihuahuas to your sled for Iditarod? No? Well there are plenty of yeast that won’t get the job done when it comes to fermenting grapes into wine.
Saccharomyces cerevisiae are the MVPs of the winery because they can survive the sugar, acid, temperature, and ethanol levels of most fermentations, meaning that they won’t die on us before fermenting all of the sugar in the must to ethanol. Saccharomyces yeasts are survivors – some even produce a “killer factor” that other yeasts can’t abide. And once a commercial strain of saccharomyces has been introduced to a winemaking facility, it’s there to stay. Winemakers spend a LOT of time cleaning and sanitizing, but wineries will never be sterile.
Some winemakers rely on “spontaneous fermentation,” meaning that they allow whichever yeasts are present in the grapes to grow and conduct the fermentation. Interestingly, most yeasts that come in from the vineyard are not our rock star yeasts. They are tamer yeasts capable of starting a fermentation, but perhaps not capable of completing it. And if there are saccharomyces cerevisiae anywhere in the facility, guess who is taking over that fermentation?
Resistance makes wine at a custom crush facility where equipment is shared by a handful of winemakers making wine for various labels. Commercial yeast strains abound. We don’t fool ourselves into thinking that yeasts from our grapes will outcompete the commercial yeasts that populate the winery. Instead, we carefully select commercial strains of yeast that will complement our fruit and inoculate the must with enough of our chosen yeast to give it a strong foothold. And by “commercial strains,” I do not mean GMO; these yeasts are bred and selected for their favorable traits.
2. We feed our yeast
Saccharomyces cerevisiae turn sugar into ethanol, but they need nitrogen and other micronutrients to do this. Nitrogen-containing compounds are found naturally in the grapes, but the amount and type vary by year and by site and by farming practices. If there isn’t enough readily yeast-assimilable nitrogen (YAN) in the grapes, the yeast may die, interrupting the fermentation, or may break down sulfur-containing amino acids to free nitrogen for consumption, leaving stinky sulfur compounds in their wake. We don’t want either of those outcomes, so we test YAN and add more if warranted.
Where do YAN additions come from? Generally, from the carcasses of dead yeast. Our rock star killer yeasts are cannibals – you aren’t surprised, are you?
3. We inoculate our red wine with malolactic bacteria
Malolactic bacteria – oenococcus oeni – turn malic acid into lactic acid. We inoculate with malolactic bacteria for the same reasons that we inoculate with yeast – we want the “A team” working on our wine.
4. We limit oxygen
While our rock star yeasts can do their work in all kinds of conditions, they require some amount of oxygen in order to not produce stinky sulfur compounds. Accordingly, we punch down our red wine fermentations 2–3 times per day to incorporate oxygen into the must. We mix our rosé juice with air from time to time during fermentation for the same reason.
Once our juice’s transformation into wine is complete, oxygen is no longer our friend. It can fuel the growth of spoilage organisms like film yeasts (yes, they are as icky as they sound) and acetobacter (useful if we were Resistance Vinegar Co) and react with wine to produce aldehyde compounds. We seal our rosé tanks to exclude oxygen. Our red wine goes into oak barrels that allow for only small amounts of oxygen to penetrate over time. We keep those barrels completely full so that only a very small surface area has any contact with oxygen.
5. We manage the acidity of our wine
Grapes naturally contain tartaric acid and, in smaller amounts, malic and citric acids. The quantity of these acids can vary a lot based on the grape variety, the site, the weather, and farming practices. Some varieties are naturally high in acid at harvest-time, and others drop acid like Jerry Garcia. If we have rain close to harvest, as we did in 2019, this can dilute acid content in the juice as well.
Some seasonal variation is part of what makes wine interesting, but if our fruit comes in way low on acid, we know that (a) the wine will taste flat and (b) spoilage organisms will eat it for lunch, literally. In that case we boost the naturally occurring tartaric acid with additional tartaric acid (which itself is generally extracted from other grapes).
6. We add clay to our rosé
No, there’s no clay in the rosé you are drinking. We add montmorillonite clay, aka bentonite, to our rosé because it has a strong negative charge and it exerts a strong pull on any proteins suspended in the wine, pulling them down to the bottom of the tank. We then rack the clean wine from the top of the tank into a new tank, leaving the bentonite and proteins behind.
Why do we do this? Because we don’t think you will buy, drink, or Instagram wine that is hazy with suspended proteins. You’re welcome.
7. We get our rosé really, really cold
When we do this, crystals of tartaric acid form on the sides of the tank. It’s one of the prettier scenes in winemaking. (Racking red wine, on the other hand, is like walking into a gruesome crime scene.) Then we rack the clean rosé into a new tank, sans crystals.
Why do we do this? So that if you stick your bottle of rosé in an ice bucket, or your fancy subzero fridge, you won’t see tartaric acid crystals in the bottle and think we’ve sold you wine with shards of broken glass. You’d probably pour the wine down the drain, which would be a travesty.
PSA: If you ever do see crystals in a bottle of wine (most likely adhered to the cork, if it was stored cork-side-down), don’t pour it down the drain! Say something clever about the wine not achieving cold stability and proceed to drink it anyway, looking like a total badass.
8. We add Sulphur dioxide
You know I put this one at the bottom on purpose, right? It’s like waving my up-to-date vaccination card in the state of Oregon. Please do not say, out loud at least, that sulfur gives you headaches.
Just so we are all on the same page, sulfur occurs naturally in grapes and wine in various forms. Elemental sulfur (S) and its elemental properties vary greatly depending on what it binds with. Elemental sulfur is often sprayed on grapevines to deter powdery mildew growth, and a small amount of it may end up in musts when grapes are crushed or pressed. Experienced vineyard managers know to cease sulfur sprays well in advance of harvest to limit excess sulfur on grapes.
But not all sulfur in wines is elemental sulfur. Thiols, which are responsible for many of the scents you know and love in Sauvignon Blanc, are naturally occurring sulfur compounds. Some amino acids found in grapes are sulfur compounds. Hydrogen sulfide (H2S) is the stinky occasional byproduct of our rock star yeasts, and it’s especially stinky when they are short on nitrogen or oxygen. In fact, there are numerous other stinky sulfur compounds (disulfides and mercaptans, mainly) that can come from sulky yeasts. Even with zero winemaking additions, there will be plenty of sulfur compounds in your wine.
Sulfur dioxide (SO2) is the one sulfur compound that is generally added by the winemaker. We add small amounts of SO2 to our wine after our yeasts and malolactic bacteria are done, primarily because microorganisms HATE it. Film yeasts, acetobacter, unfriendly strains of lactic acid bacteria… they like SO2 even less than “natural winos” do.
Bonus fact: SO2 also inhibits various oxidation processes and binds acetaldehyde, a byproduct of oxygenation, which neutralizes its odor. SO2 takes different forms depending on the pH of the wine, and the amount of SO2 needed to achieve microbial protection increases as pH increases – another reason to manage our wine’s acid levels.
Hey, if you like reading about wine, you’ll definitely enjoy drinking it. Check out the Resistance Wine Company’s best bottles!