The other day I had a very lovely debate with one of my guests on a topic of sediment. He had a background of being some kind of a health and safety inspector, specialising on restaurants, bars overall hospitality.
I served half a bottle of Comtesse de Lalande Reserve. It was a new vintage 2009 and at the end, we both discovered a minuscule amount of sediment. It wasn’t an issue at all, but our conversation started when he asked about it; how does it influence, what does it do and so on. Ofc after apologising I tried to explain that it’s a rather good signal showing that wine had spent some time in a bottle, and had developed so far to compose sediment. I also stated well-known fact that it doesn’t affect or do any harm to your health. It’s edible, but it’s unpleasant. He disagreed with me, unfortunately, didn’t give any good explanation why this natural byproduct is bad. I tried hard to pursue him thinking that this natural occurrence/chemical reaction is rather a good thing FOR the wine. I somehow remember reading about it, that it helps the wine to continue developing some extra aromatic and organoleptic nuance. He wasn’t convinced and left me to hesitation and desperation on sediment topic.
Sediment thoroughly and shortly:
So there’s two types of deposits: colloids and tartrates. Colloids are smaller and grainier types of pigments, polysaccharides and protein. They form slowly and develop after few years. I had a real experience with colloids when I opened Italian; Piemonte-based Luigi Einaudi Barolo 2004->
The second type of sediment is caused by the formation of potassium bitartrate crystals (potassium and tartaric acid occur naturally in the grape and wine). Cooler temperatures help to form that crystal. Usually, more commercial wines are kept in the barrel over few winters, with that winemaker can filter the sediment out prior bottling. Here comes alcohol which tends to block all the crystal of forming, and that’s the reason why all the red wines might continue creating some sediment. Ofc winemaker can bring the wine to a very low level of Celius for few weeks to maximise the formation of all the crystal. Let’s be honest, that’s not very healthy for the wine.
Simply sediments are composed of residual yeast, grape seeds and other particles which settle to the bottom of the vat. It’s not scientifically proved that the deposits increase organoleptic values of the wine but winemakers do believe that leaving wine unfiltered will increase depth and flavour. And I do believe people who make the wine and understand it more than anybody else.
Wine is a dynamic, natural beverage that is meant to change and transform over time. Sediment is evidence of its native ability to change.