So you want to make white wine

I should preface this by saying that I’ve only learned how to make white wine in New Zealand and Bordeaux so if you’re interested in how to make Sauvignon Blanc and Sauvignon Blanc, this is the blog for you! That said, 90+% of this will also apply to other varietals.

In my last blog, I talked about my love/hate relationship with “natural wine.” I’m a huge biodynamics fan and a sustainable viticulture junky, but to paraphrase Einstein, “Everything should be made as simply as possible, but no simpler.” For me, this idea was reaffirmed at last weekend’s La Dive natural wine festival in the Loire, where I tried many great red and orange wines, but I have to say that the white wines ranged from OK for the best ones and undrinkable for the worst. I can honestly say it was the first time that I smelt Brett in a Riesling. From a winemaking perspective, good natural red and orange wines makes sense because red wines and orange wines (*orange wine: think Rosé for white wines: skin-macerated for 12hr – few months) have the protective antioxidant barriers in the form of tannins and anthocyanins. Natural white wine on the other hand are much trickier…

Before I came to Bordeaux for this Master, I swore to my hip, natty wine friends that I was just coming here to learn the enology behind it all just so that I could then know how to break the rules later. This still holds true. Mostly. The more I learn though, the more I can feel myself being sucked into the science-based thinking... because like duh. Also... just as Bordeaux was at the forefront of hyper-intensive winemaking practices, I've come to realize that it is also at the forefront of minimizing them and finding more sustainable alternatives.

My recent love affair has been with white Bordeaux. Sauternes and sweet wines will have to wait for another blog, but now we will speak about the dry whites, which in my opinion can be some of the most expressive and interesting wines of Bordeaux (not to mention the best ones ring in at about 30 euro.) Bordeaux’s bankroll and name may very well be built on the great reds such as Petrus and Chateau Lafite, but the appellation’s white varietals, Sauvignon Blanc and Semillon, are some of its best kept treasures.

These varietals are high in volatile thiols such as 3MH and 4MMP, which have the precursors of grapefruit and guava aromas respectively. The aroma liberation occurs during alcoholic fermentation by the yeasts. Since these aromas are the signature of Sauvignon Blanc (think “boxwood” and “cat piss” from 4MMP), we try to preserve these volatile thiols. For example, viticulturists do this by avoiding late copper treatment in the vineyards and by making sure that vine nitrogen is sufficient. 

In Bordeaux, we normally harvest the grapes at Brix 20-23. In New Zealand, it was more like 25-27 (with a subsequent lingering visit from the “white snake”). Top BDX Crus will invest in multiple selective hand-harvesting dates within the same plots to ensure the ideal maturity when picked.

After the fruit is brought to the winery's reception area, white varietals are generally destemmed and crushed. However, in Bordeaux, we whole-cluster press Sauvignon Blanc and Semillon, which minimizes the use of clarification products, e.g. bentonite. The tannins from the stems will form a colloidal bond with the proteins naturally present in the juice. Sometimes, this is proceeded by a skin-contact maceration but we have to be careful about the ensuing increase in pH (a less acidic white wine with a pH > 3.7 will be more susceptible to microbial risk).

To protect the juice from oxidation, SO2 is often added after the press along with carbonic ice. About 1-2 weeks after the alcoholic fermentation, SO2 is again added. If added too soon after AF, the unpleasant rotten egg H2S aromas will form due to a reaction with the enzyme sulfite reductase. Concerning alcoholic fermentation in oak, interestingly enough, recent studies have found that wines are less marked by oak when alcoholic fermentation occurs in barrels, due to yeast metabolisms, giving a decrease of the vanillin aroma by yeasts into vanillic alcohol (which is odorless).

Contrary to red wine aging, white wine aging is reductive. Red wine aging is oxidative due to its natural antioxidants previously mentioned. Since white wine doesn’t have many tannins or anthocyanins, it needs to be protected from oxygen. The best way to do this while minmizing SO2 use is to keep the wine on its lees (*Lees: dead yeast particles that still contain lots of nutrients that form at the bottom of a barrel or tank). If aging occurs in barrels, age on total lees while stirring once per week. If aged in tank, it is best to age the white wine on fine lees only. The wine is then kept on lees for 8-12 months.

During the clarification, the turbidity is normally adjusted to 50-200 NTU (2-3% solids). First with a natural settling and if needed, with pectic enzymes.

Or if you just like graphics, check out this awesome illustration by Wine Folly.

Et voilà! Nerdy lesson on how to make white wine. Obviously, there's no recipe: each terroir, situation, and type of wine produced demands something different (e.g. a 3 Euro Bordeaux wine is not produced like a 45 Euro Bordeaux Wine) but that's more or less, the foundation of it all.

So... invite some friends over: buy one white wine from Bordeaux, one from Marlborough, NZ, and one from the Loire, all of about the same value; and see what differences you pick out. 

SBs to try:

Bordeaux:

Chateau Carbonneiux

Clos Floridene

Chateau Olivier

Natural wine: Julien Auroux – Bergerac; Sauvignon Blanc and Sauvignon Gris

Loire:

Domaine Vacheron

Clos de la Bergerie

New Zealand:

The classic: Cloudy Bay

Dog Point