Waiter, Waiter! Why are there fish, eggs, milk & nuts in my wine?
Have you ever noticed…
…On the back of wine labels that your wine may contain fish, egg, milk or nut products? Have you scratched your head to wonder why a product made from grapes would include this warning? It’s because of fining – also known as clarification – a process winemakers use to remove any potential hazes and instabilities from finished wines. It is definitely worth understanding, particularly if you have certain dietary restrictions or if you’re vegetarian or vegan.
After giving the wine sufficient time to clear itself as much as it can, the winemaker can finish this process by adding a fining agent. Philip Wagner wrote a book called ‘Grapes Into Wine’ in which he summarises fining: “When a wine is fined a sort of veil of the fining material is drawn down through the wine, dragging all the suspended matter with it”.
A common fining agent used is ‘bentonite’ which is essentially a clay derived from volcanic ash. It seems odd that adding clay to your white wine could actually make it clearer, however bentonite attracts proteins in wine, which if not removed could form a haze if the wine is exposed to excessive heat in storage, or in the boot of your car on a hot day!
It actually works by chemical “magnetism” – bentonite that has a negative charge and attracts positively charged proteins and binds them to itself. Over time, the bentonite and proteins settles to the bottom of the wine and the clarified wine is racked away from the sediment.
There are other fining agents you can use to clarify wines, such as gelatine (a substance extracted from the protein & peptides of cow, fish, chicken or pig’s skin, bones & tissues); egg whites; milk protein (winemaker’s often use skim milk powder); seaweed extract (also known as Sparkalloid); or even Isinglass which is purified sturgeon’s bladder – sturgeon the fish, not those operating doctors!
It’s important to choose a fining agent that has the opposite charge to the potential haze being removed to ensure the wine is clear. Sometimes two different fining agents of different charges are necessary to completely clear any hazes. Here is a table of some of the most regularly used fining agents and their respective charges:
POSITIVE OR NEGATIVELY CHARGED
|Bentonite (Volvanic Clay)||Negative|
|Isinglass (Fish bladder)||Positive|
|Kieselsol (Silicone Dioxide)||Negative|
|Sparkalloid (Seaweed extract)||Positive|
Fining versus Filtering
Fining is different to filtering wine. Filtering is a mechanical process which acts like a sieve that allows the wine to pass through but traps any physical particles in the process too large to pass through the filter. Fining wine acts on a colloidal level – it traps the sub-microscopic particles which make up hazes (known as colloidal particles) which wouldn’t be able to be trapped in a mechanical sieve. These colloidal particles carry a very small positive or negative electrical charge.
When two colloidal particles carry the same charge they repel one another and bounce throughout the wine potentially creating a haze. If a fining agent is introduced with the opposite charge, much like introducing a larger, oppositely-charged magnet, the particles will be attracted to that agent and they will bind together to create a heavy mass of particles which will sink to the bottom of the wine vessel.
So what does SHORT SHEEP do?
At SHORT SHEEP, we always try a minimalist approach when it comes to intervention in the winemaking process. We avoid using additives unless absolutely necessary, but if we do then we prefer not to use animal-derived products, such as gelatine, isinglass, and whatever product we do use, we endeavour to always use the minimal amount necessary to be effective.
We think our handpicked grapes are sensational, so our philosophy throughout the whole winemaking process is to KEEP IT SIMPLE & let the varietal and vintage character of the wine show through. We’re not interested in over- sanitising our wines and are proud that our wine differs each vintage and that it’s filled with the grape varietal characteristics. Sometimes our approach means a little sediment forms within the bottle – a sign that there has been much less interference and stripping of the natural wine characters.