Why So Much Sulfites? An Open Letter To Natural Wine Buyers

Hi _____,

Thanks again for taking the time to try our new wine. I just wanted to follow up to see if you had any feedback or would like to make an order?

I also wanted to provide a more thoughtful response to your questions when you tasted. Specifically, when I mention we added a total of around 40 ppm of sulfites, you wanted to know why so much?

Honestly, that caught me off guard at the time as in my head I use the Raw Wine standards as a reference for what would be generally considered acceptable levels of sulfites (below 70ppm) in the natural wine world. 40 may seem high compared to zero, but considering that naturally occurring sulfites are often over 10ppm, I don't really think that I'm altering the wine at that level, but rather protecting it. And allow me to get technical...

While use Zero sulfites is always an option, it is always also risky if you want to avoid microbial blooms - the most common of which are acetobacter, pediococcous, brettanomyces, and the cocktail that causes mouse taint. I am strongly averse to the development of detectable levels of these microbes as I don't find their taste to be unique. They are really the same in every wine you taste. Therefore, I aim to preserve the unique expression of the fruit and its terroir, so I don't have a severe philosophical aversion to sulfites.

Part of my aversion to these microbial flavors is that I want to promote the agriculture behind my wine, rather than my winemaking philosophy. The agriculture behind my wine affects the planet and everyone who lives in it, so it's much more important to me to highlight organic, regenerative agriculture beautifully, rather than stick to my philosophical guns regardless of whatever develops in my wine. I want the majority of wine drinkers to actually like the flavor of the wine, and see the benefits of organic farming.

And so I almost always choose to add some protective sulfites. Not an amount that sterilizes the wine by any stretch, but enough to effectively inhibit runaway microbial infections. The lowest amount of sulfites generally accepted as effective is 15ppm. Below that you may as well not add any. Without that amount, some level of volatile acidity (VA) caused most often by acetobacter, is highly likely unless you're fortunate... it's probably less than 50/50 odds you'll avoid it. Even with that amount you can have issues, as you’ll see.

Another thing, techically, to keep in mind is that the effectiveness of sulfites is influenced by the pH of the wine. The higher the pH, the more sulfites you need to be as effective as a lower amount at a lower pH. There are other factors too, and that's part of the skill and science of winemaking.

The rose noir (Noctilucence) is something I wanted to be fruity and fun to drink. So to protect the fruity freshness of the organic and biodynamic syrah, I added 15ppm after crush. After fermentation and malo-lactic conversion, the pH had risen, and the levels of acetobacter had grown to a level that I - who am a sensitive taster - could detect. We also do lab testing pre and post crush to monitor these things, and found raised levels of VA (explaining why I was smelling it). Based on all the factors involved and the growing levels of acetobacter, I added another 20ppm sulfites to prevent a VA bloom. It worked beautifully. The sour smell disappeared and the wine became fruity and delicious again.

Then we did another lab test before bottling, and discovered we had almost zero Free SO2... which, if you are not going to filter and you've had a VA issue already, risks having VA develop in bottle, so we added another 10ppm. Some of that is absorbed/bound up immediately, and more is bound up during the bottling process. So though we added approx 45ppm total throughout the life of the wine making, the remaining free SO2 in bottle will be less than 10ppm. This allowed us to minimize the risk of our beautiful organic and biodynamic fruit ending up tasting of vinegar, so consumers can connect positively with this beautiful agriculture that is really the biggest impact on the health and well-being of everything on the planet... which is our goal.

I apologize if this comes across as pedantic. You probably are already aware of much of this anyway, but I just wanted to explain our thinking and approach to wine. We are definitely not zero-zero zealots, so maybe that means we won't be right for some of your customers. We're okay with that, because our mission is really to promote the agriculture not the winemaking.

Thanks again, and I really do appreciate any feedback!

Adam