I am a chemist and enology researcher who has spent years researching wine and the winemaking process. In order to explain the differences between vegan and non-vegan wines, let’s first go over the basics of winemaking.
Let’s start by filling up your glass.
The grape’s journey from the vine to the bottle is long and tortuous. Shutterstock
Read more: No, putting a spoon in an open bottle of champagne doesn’t keep it bubbly – but there is a better way.
How conventional wine is made
The grapes are a major part of the winemaking process, both white and red.
The skin of the grape is used to ferment red wine since this is where molecules that give the color are located.
The additions and manipulations are extensive. To ensure a controlled fermentation, yeast is usually added with diammonium, a nitrogen source.
Add enzymes to the wine to either break down pectin, a fiber found in fruits, or to improve flavor. Red wine, as well as some white wines, use malo-lactic fermentation (where the grape’s lactic acid is converted into malic acid).
The larger fine lees can be removed through filtration, while the gross lees can be removed using “racking,” which is moving wine from vessel to vessel.
The wine must be finished before bottling.
Before bottling, wines are tasted. This is the stage when decisions are made about whether the young wine needs to be adjusted in terms of its palate structure.
A wine can have a drying effect on the mouth (known as astringency) or a slight bitterness. It can occur when the polyphenolic compounds, which are micronutrients found in plants, are higher than desired.
The tannins in red wine are polyphenolic compounds, which are macromolecules composed of carbon, hydrogen, and oxygen atoms. In white wine, the molecules are smaller and are referred to as “phenolic compound”.
Phenolics interact with proteins. Imagine adding milk to a strong cup of black tea in order to give it a rounded and less bitter flavor.
After a taste test to determine the correct amount of protein, winemakers will add one allowed protein additive. Fining is the term used in the wine industry to describe this process.
Here’s the problem with vegans
Here’s where vegans have problems.
Gelatine derived from cow or porcine collagen, isinglass derived from fish swim bladders, and egg white or skimmed milk are the most commonly used proteins.
Winemakers choose which protein to use according to their experience or advice.
Before bottling, wines are tasted. It is often at this point that a decision may be made about whether the young wine needs to have its palate structure adjusted. Shutterstock
Australia has strict rules for wine labeling that include the requirement to list allergens.
It includes eggs and milk but excludes other animal-derived proteins. It can be not easy to know which wines are vegan-friendly.
On some wine labels, you will see a statement like “this wine may still contain traces of fish product.”
In Australia, and particularly in Europe, wine is now more often labeled as “vegan friendly” or “no animals products were used to prepare this wine”.
What are alternatives to animal protein?
This is the stage of research for most plant proteins. Commercially, only derived from potatoes can be purchased.
Red wine contains gluten from cereals, which is good for the coeliac or gluten-allergic but causes problems for those who have it.
Grape seed extract has been tested as the most potent plant-based protein but is not available commercially. The difficulty hinders the commercialization of new wine-related products in obtaining regulatory approval on international markets.
After removing the gross lees, storing wine in its fine lees can be an alternative to adding animal proteins to winemaking. This will soften the wine and improve the mouthfeel without adding any additives.
The white wine can be aged on fine lees for up to nine months. Reds may require up to 18 months for the desired mouthfeel.
It is important to taste the wine regularly during this step of aging in order to make sure that it is developing according to your expectations. This is an expensive process, as it takes up winery and storage space.
Taste test
In a recent wine tasting, I showed some wines that were produced using the conventional method while others were vegan-friendly. After the tasting, the general consensus was that I couldn’t distinguish the differences.
It is not only vegan food that can be paired with vegan-friendly wine. In a classic example, a sweet French vegan wine from the Loire Valley was described as being “excellent with foie gras.”
