Ask Jim: Bottle sludge, a good sign?

By Jim Chatto
Subscribe to VisitVineyards.com
Leading young winemaker, Jim Chatto

Leading young winemaker, Jim Chatto

 

Dear Jim,
My husband came home with a case of red wine that he got for $50 from a mate at work, but all the bottles have a thick black silt in the bottom of them. My husband says it’s a sign of a good wine (for $50!!). They are a 2001 Cab Sav Merlot from Adelaide Hills - are they okay to drink and what is this gunk?
MSlemier, WA

 

It is true that reds wines can throw a silt or sediment as they age in the bottle. However, it would be very brave person to credit this as a measure of quality.

Most sediment in red wine occurs over a very long period, five to 50 or more years, and results primarily from the polymerisation (binding together) of phenolic compounds such as tannins and colour molecules. As these polymers become larger they are less soluble and thus fall out of solution forming a sediment. The result is a softening of the wine as larger tannin molecules tend to be less astringent than their smaller counterparts and the tannins that precipitate do not contribute to astringency at all.

However, there can be other reasons for sediment in the bottle, especially in relatively young wines, which are more sinister indeed. This type sediment can occur from the growth of micro-organism such as yeast and bacteria leading to undesirable characters in the wine such as volatile acidity or VA (mentioned in a previous column, see related links below) spritz or fizziness, as well as many other off taints.

I would be very sceptical of a young and especially cheap red wine with any kind of sediment. The alcohol content in wine, typically 12 to 15 percent in reds, is more than sufficient to kill off any microbes that may harm humans, so I would expect it is safe to drink - though your palate may not thank you.

That said if it tastes good then you have got a bargain! I would recommend decanting it prior to serving.

 

 

Got a question? Send it to Jim Chatto.

Please note, Jim will endeavour to answer as many questions as he can, however there may be delays between submission of questions and publications. Emails will not receive personal responses.

Our Recommendations

To see our recommendations, ratings and reviews you must be a logged-in subscriber.

To subscribe please enter your email address in the "Subscribe Now - it's Free" box on the right and click the "Join" button, or fill in this form >

 
Subscribe today - it's free
Subscribe Button

Subscribe now - for news and reviews, our newsletter (optional), to join our forums, and more.

Enter your email address and click the Subscribe button. We respect your privacy.

Log in

Enter your username...

Enter your password...

Log In Button

Forgotten your password?

Subscribe

Kerry's corner - your free benefits

Advertisement

Competitions
Mornington Peninsula (Vic): Peninsula Summer Music Festival - 1-10 Jan 2020

Jancis Robinson

This summer, the Mornington Peninsula will once again be filled with the sounds of world-class music at the annual Peninsula Summer Music Festival »