What to Do About Wine Stains?
What makes wine such a pesky stain?
Most wines are made from grapes. And these grapes appear to be full of colorful juices.
A bottle of wine can range in cost from about $2 to $75,000 depending on the vintage. One thing that they all share may seem like a disappointment: they’re all about 98% water and ethanol. But it is the other 2% that makes up the taste… and the stain.
What makes up this 2%?
There are more than 10,000 varieties of grapes in the world. In addition to these different species of grapes, distinct minerals in soil and climates produce different tastes and smells (and stains).
There are up to 60 trace elements in wine that can trace wine back to its specific location of origin and even where the trees are from that compose the barrel - almost like each wine has a chemical fingerprint. Here are some of the elements:
- Grapes contain astringent tannins in their seeds.
- The juices contain sugars, acids, and water.
- The skin is quite complex and contains anthocyanins, quercetin, resveratrol, tannins, and catechins amongst many other compounds—this is where most of staining comes from.
- Acetic acid, malic acid, tartaric and pyruvic acid contribute to the color as well by controlling the pH, and contribute to the wine staining as it makes the natural dyes acidic and red.
- Pyruvic acid supplies energy to living cells through the citric acid cycle when oxygen is present (aerobic respiration); it ferments to produce lactic acid when oxygen is lacking (fermentation).
- Diacetyl (buttery aroma in white wine), methoxypyrazines (bell pepper aroma), and ethyl acetate are other distinguishing chemicals found in wine.
These make up the flavors, but they are not so relevant to staining.
What is most relevant in this chemistry to what I’m trying to remove?The most often cited chemistry associated with wines are a class of compounds called tannins.
Wine aficionados talk a lot about tannins; it basically refers to the dryness, bitterness, and astringency of a wine.
Tannins are part of a broader group of chemicals called polyphenols, which come in both hydrolyzable and condensed varieties.
The condensed tannins are mostly responsible for the color and taste (dryness) of wine. The smaller the particular tannin molecule, the more bitter and astringent it is.
There are polyphenolic-tannin compounds called anthocyanins, which are found mostly in the skins of grapes. They are water soluble pigments that are purple, red, and blue and their color depends heavily on the pH of the soil in which they are grown. This color as a chemical is actually odorless and nearly flavorless! It’s weird to think that the redness in wine isn’t actually the source of any of its flavor.
The colored part of the polyphenol is often referred to as a chromophore. Chromophore typically refers to a conjugated pi-system, which is an overlapping electron orbital and when the electrons jump different distances, they appear as different colors to the human eye.
Another compound that makes up the color in wine is quercetin.
Quercetin (yellow color) is an antioxidant and anti-inflammatory and may contribute to some of the potential health benefits of wine. This tends to be in higher levels the more exposed the grapes are to the sun.
This is key: Oxygen causes these polyphenolics to oxidize and bind to fabrics thus becoming harder to remove if you treat them too late. So, honestly, the key to wine stains is FAST ACTION!
Now that we know that wine is an acid-dye, astringent, complex, colorful juice loaded with dyes and tasty chemicals.
So how do we clean up the stains?
Wine stains are adversaries to hydrogen peroxide, which is lucky-for-us, a common household item and is an excellent and natural (Still use with caution! It is technically an aggressive oxidizer). The consumer-grade of hydrogen peroxide is 3% peroxide and 97% water to make it relatively safe.
Fun fact: 90% grade hydrogen peroxide is used as rocket fuel.
With that, we recommend this process:
- Dilute 1 part hydrogen peroxide in 2 parts water. This makes a 1% solution of hydrogen peroxide.
- Apply the hydrogen peroxide solution to the stain as soon as possible after the accident. Let it sit for 3 minutes, then rub and rinse using cold water.
- If Dirty Labs detergent and laundry machine are accessible and the garment is machine-friendly, apply both the hydrogen peroxide solution and Dirty Labs detergent to the stain as soon as possible.
- Let it sit for 3 minutes, then throw it into the washing machine and wash using cold water.
If this is working well, but the stain isn’t quite gone yet, step-it-up to the full concentration of the 3% peroxide. (Some exceptionally sensitive or new garments with fresh dye could be more susceptible to color loss using 3% peroxide, which is why 1% is recommended initially. If the garment is white or light in color, then this generally will not be an issue.)
After you treat the stain, wash the garment ASAP. If not, blot it as much as possible with clean white rags and you should be able to remove it… if it is not too late.
Wine is easy enough to remove if you act quickly. For set in wine-stains, if peroxide does not work, try using an oxygen booster.
Enjoy your wine and try not to spill!*
Troy, Dirty Chemist
PS. In honor of National Rosé Day, we partnered with Union Wine Co. to get you 30% off your order with code WINEANDLAUNDRY30. Shop Now.
*Always drink in moderation.