What’s in my wine?

what's in your wine

Let us share with you a dark little secret that even the most enthusiastic wine lovers are often unaware of: Wine producers don’t have to tell you everything that goes into your wine.

Sure, you know there’s…well…grapes. And you probably realise that most wines also contain some sulphates and/or sulphites (often indicated by a preservative ‘number’ on the back of the bottle. Read more about preservatives in wine.)

But did you know that the majority of wines are processed and bottled with a list of extras longer than a Robert Altman film? Here we take a look at some of the more common additions to your wine.

What’s in my wine?

Sulphur dioxide/Sulphites

We’ve covered these in detail before, but the addition of sulphur is used to protect the wine from oxidation and therefore preserve the flavours and aromas of the wine as the winemaker intended.

Potassium Sorbate

Like sulphur, potassium sorbate fights off bad bacteria. In sweet wine, it’s also often used to prevent a secondary fermentation (which causes spritzy bubbles) once it’s in the bottle.

Tannin powder

If a wine is lower in natural tannins than the winemaker would like, they are permitted to add some tannin powder. This is usually made from a mix of grape seeds, skins and wood (like oak.)


Certain enzymes – like pectinase, which is most commonly used – remove unwanted compounds from the grape skins and help clear out any little microscopic leftovers.


Grapes that are a wee bit under-ripe tend to have less sweetness and therefore there’s less sugar to ferment into alcohol.  Winemakers can choose to add sugar to wine to increase alcohol, and it may also be added before the wine is bottled to sweeten the flavour and lower any unwanted astringency.

While adding sugar to wine is actually an illegal practice in Australia, it’s common in other parts of the world. So next time you’re reaching for a cheap import, remember that.

Oak chips or powders

Looking to cut costs on those expensive oak barrels? Fear not! Just add pre-flavoured wood chips. Bleh.

what's in my wine

Tartaric, Malic and Lactic Acids

Acid is essential to wine production and it affects the number and type of microbes present, as well as the colour and aging potential of the wine. Sometimes, the grapes being used just don’t have enough naturally occurring acid to create the desired wine. Tartaric acid is the most common addition, but malic and lactic acids are also naturally occurring and often blended with tartaric into low-acid wine. Citric acid can also be added before bottling to add a racy lift to white wines.


No surprises here. Yeast is the key ingredient that turns grape juice into wine. It eats up the sugar and converts it into alcohol. (Thank goodness for that.) Traditionally, the natural yeasts in the air have done the job, but to control the process and get a more predictable outcome commercial yeasts are added by the winemakers. If you purchase a wine that’s labelled ‘wild ferment’ then it’s been made the traditional yeast-in-the-air way. All others have yeast added. Yeast also affects the bouquet, mouthfeel and flavour of the wine so the type of yeast chosen is significant to the overall result.

Fining Agents

Ever read on the back of the bottle ‘May contain traces of egg’ and thought “What the???”. Here’s the deal – egg really is used in wine production, during the refining stage. If you’ve ever made a consomme this will sound all too familiar. Suspended particles naturally occur in fermenting and aging wine. These particles cause cloudiness and sediment. Winemakers clear the wine by adding agents that cling onto these floaters and absorb them.

Egg whites and gelatin are especially effective in clarifying red wines. Casein, a milk protein, is often used to clarify white and rosé wines. Some fining agents, however, are chemical based and a whole lot nastier…Although this may cause your radar to go on high alert you can take some comfort in knowing that they’re pretty much filtered out before bottling.

Fish Bladders

Had to give this it’s very own category just for the sheer gore factor, but really it’s just another filtering agent. Known as isinglass, it can be used to actually remove some of the bitter tannins as well as particles in the wine.

Bentonite Clay

Not just good for facials, Bentonite Clay is widely used to prevent formation of cloudiness or haze in white and rosé wines.  It’s not used in red wine as the natural tannins in red wine perform the same role.


Possibly the most terrifying thing of all is that there may be soluble plastic in your wine. PolyVinylPolyPryrolidone, or PVPP, is a a permitted additive that eliminates unwanted or unattractive colours and helps stabilize the wine. It’s meant to be all removed again via racking and filtration but there is no requirement to test the wine for any residual or remaining PVPP.

Yeast nutrients

When yeasts get a bit lazy on the job and winemakers don’t want to feed them sugar to get them going, they add nutrients instead. Basically a multi-vitamin for yeast.

Acid reducers

Some grapes contains too much acid for the desired wine being made, so minerals like calcium carbonate come to the rescue. Think of it as Mylanta for wine!

Next time you’re reaching for a glass – or bottle – of wine, think carefully about where it comes from and who has made it. The more you know about it’s origins and makers, the more you can find out about what’s inside it.

Here at The Fabulous Ladies’ Wine Society we’re passionate about introducing you to beautiful wines, made by gorgeous people who care about what’s in the bottle.

JOIN NOW – It’s free!


  1. Wow didn’t have idea. Thanks Jane!

    1. Pleasure Mary! Glad you got something out of it 🙂

  2. Wow didn’t have idea. Thanks Jane!

    1. Pleasure Mary! Glad you got something out of it 🙂

  3. Teresa Bassham

    Fantastic article Jane – a good argument for quality wine – frightened me a bit lol!

    1. The Fabulous Ladies

      Thanks Teresa!

  4. Teresa Bassham

    Fantastic article Jane – a good argument for quality wine – frightened me a bit lol!

    1. The Fabulous Ladies

      Thanks Teresa!

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