What's Done to Wine in the Cellar?

First off, I'm not a winemaker other than a bit of homemade stuff. Actually, if I was a winemaker, I wouldn't be telling you many of the things done to your wine. Second, nothing mentioned here will hurt you. Everything done in the cellar is to make the wine better, or sometimes to save time or money, in the opinion of the people making the wine. Sometimes it's for taste, sometimes for looks. The U.S. gov't, the TTB, controls what can legally be added. 

There are two groupings of wine manipulations, things added and processes done to the juice or wine.

Adding a bit of sulfur to wine aging in barrels
to kill off microbes, yeast, and help prevent oxidation
image from gravitywinehouse.com

Some of the common ingredients added to a wine

Sulfur - A preservative that naturally occurs on grapes, but more is added during the stages of wine making.

Yeast - You wouldn't have wine without these little guys.

Tannin - One of the main components of a wine, tannins come from grape skins and seeds. Sometime more is added in powder form.

Acid - Another main component of a wine. Several acids are naturally occurring in grapes, plus tartaric, citric, and malic acids are often added. There are de-acidifiers for wine with too high acids, like calcium carbonate (the active ingredient in Tums).

Sugar - In some countries getting the grapes ripe can be an issue, so they allow chaptalization, adding sugar to the grape juice before fermentation.

Fining agents - These can be egg whites, gelatin, Pepsin (comes from animals), or other substances used to clarify the wine. This is where vegans might have a problem.

Grape concentrate (aka Mega Purple) - Adds dark purple color and a bit of sweetness.

Some of the common processes used on a wine

Cold soak - Crushed red grapes kept at a cold temp for a few hours to a few days to increase color, aromas, and flavor. Keeping the grapes a few degrees above freezing, usually with dry ice, prevents fermentation from starting prematurely.

Filtration - This can be done by gravity for coarse filtering to filter pads for finer filtering. Filters come in different micron sizes, allowing the fine-tuning of what gets removed. Very fine filtering leaves the wine the most clear and brilliant, but possibly at the expense of aromas, flavors and other compounds you may want to keep.

Lowering the alcohol level - Watering back, reverse osmosis and spinning cones are ways to do this when you have overripe grapes. Watering back is common because it's easy and cheap.

These are just a few of the things that may be added or that can be done to the juice before fermentation or to the wine afterward. Some things have been done for centuries, many are considering modern wine making techniques, others are a response to climate change.

Consumer interest in low intervention winemaking

In response to what some consider heavy-handed wine making, you find consumers interested in organic, natural, or other low intervention wines. This is a small, but growing sector of the premium wine market, led by younger consumers.

Is lower intervention better? The wines will often be different because, as I said, these steps are taken to improve the wine in the winemaker's eyes, but the question become, how much of this manipulation is really necessary?

Whether you're okay with using fish bladders as a fining agent in your wine is up to you. But how do you know? You don't. Unlike food items, wines aren't labeled with ingredients let alone what processing was done, like lowering the alcohol.

Alcohol ingredient labeling

Alcoholic beverages are regulated by the TTB, a tax agency. Other consumables are regulated by the FDA which requires nutritional and ingredient labeling. This is the simple answer as to why you don't see these labels on your adult beverage.

Winemakers seem to not want you to know, as they are mostly against wine ingredient labeling. Why? Because you might be concerned when you see something like copper sulfate (removes the rotten egg sulfur smell) on the ingredient list. People are definitely afraid of sulfur in wine, because of the warning label on the bottles, when less than one percent of the population is actually affected by it.

If you don't know what an ingredient is when you are going to ingest a product, you may naturally be concerned. Taking time to learn about each item on the ingredient list is not something most consumers will do. This is what winery people are afraid of.

Opinion

Is there over-manipulation in wine? Yes, because too much of it tastes all the same, has the same color, even has 14.5% alcohol (14.9% or 15.5% if it's zinfandel). This is more prevalent in the less expensive end of the market and in mass-produced premium wines.

Way back when, Gallo Hearty Burgundy jug wine was very popular as an everyday wine. Someone once pointed out to me that somehow it tastes exactly the same every year! I wondered, how do they do that? I expect they had a bunch of very smart chemists figuring that out. Gallo wisely did this because that's what the consumer expected. Folks buying $3 jug wine don't care about vintage variability. Just like their beer or liquor, or soda, for that matter, they expect it to taste the same every time.

So, it there a place for what I call over-manipulation? Yes. Do I expect a homogenous product when I buy a premium wine? No.

A snack item ingredient label. Yikes.