Can you share your thoughts on this and how you might do this with a white wine. Thinking along the lines of Kongsgard’s techniques. Any benefits to this versus reductive winemaking.

There are four ways to make white wine. I’ll address them in order of popularity in today’s marketplace, which also happens to be reverse order of historical emergence.

Method 1: Reductive. This was impossible before WWII and the emergence of sterile filtration (a product of atomic energy and the Manhattan Project), stainless steel, inert gas, and electricity. The poster child to day is NZ Sauvignon Blanc. In this regimen, oxygen is held to be the enemy of freshness for delicate varieties, and in the extreme example, dry ice is used to blanket grapes at harvest and tannin is minimized at every stage because oxygen will not be available to refine it, thus only such anaerobic techniques as fining and ultrafiltration are available.

Method 2: Hyperoxygenation. Method 1 doesn’t work too well for the aromatic varieties such as Riesling, Viognier and Arneis, which tend to be high in tannins no matter what you do. When these see oxygen, the generate H2O2 which attacks and oxidizes terpenes, resulting in petrol aromas and dullness. A commonplace technique in the Mosel is to bring three saturations of oxygen to the must in the absence of SO2. Musts are incredibly reactive to oxygen, consuming a saturation in about 45 minutes. This can be performed with air to float solids and separate pulp at the same time. After treatment, musts are sulfited and then treated reductively. These musts turn muddy brown – it’s very scary. But the result is wines which are light and delicate that maintain freshness quite nicely.

Method 3: Structured sur lees. Here the tannin of, say, Chenin Blanc or Melon is utilized as a skeleton onto which autolyzed lees are attached, often in the presence of small amounts of oxygen. These wines take a long time to come around, but can be great. My 2003 WineSmith Chardonnay is such a wine.

Method 4: Orange Wines. This is the oldest method, originating in ancient Georgia, Turkey and Macedonia, and now practiced most famously in Friuli. I will discuss this method over in Tom Hill’s thread on the subject.

Each of these methods sends the wine in a radically different direction. IMO, much incoherent white wine results from mixing these methodologies.

Regarding NZ, I thought most of the sauv blanc was machine harvested and that this would necessarily entail a significant amount of skin and oxygen contact. No?

They do perform a lot of skin contact, it’s true, but are relative Nazis about excluding oxygen. Some wineries are more fastidious than others, and charge for the privilege.

Not everybody in the Mosel does hyper-ox either. We could spend a lifetime dissecting these variations, and many do.

The point here is to understand the four general methodologies’ strengths, weaknesses, tradeoffs and challenges.

Regarding the hyperoxidation MO, following aeration, there is a chill/settle/rack stage prior to fermentation, right? There is for me with viognier.

I’m not certain whether it’s necessary. I do know that if you don’t the initial results are dubious until it clarifies, and I suppose there is some potential for redissolving. The really cool way to do it is with flotation, so you remove precipitate as you go and don’t tie up the tank.

Without racking the juice, wouldn’t there be trend towards excess reduction during ferm.?

I’m not sure. The material is already oxidized, but phenolics are tricky. The initial oxidation products are even more reductive than the initial monomers, but they eventually give it up and are quenched. Couldn’t say. This is a good opportunity for experiment, but I’d say the safe practice is to settle-and-rack or float off the solids for all of these reasons.