Common Wine Faults Are these 6 issues actually wine faults? What do we know about them? How do we rectify them? Wine is poured into a glass, particles of cork are visible, floating in the glass…. Not a “fault” at this stage; it is perfectly acceptable to pass the wine through fine muslin into a decanter, use a clean cloth or bar spoon to gently pick up pieces from glass if necessary. Happens either because cork dried out at some stage (get to this later) or because server has broken cork when opening.

Wine has a brown tint, especially noticeable in white wine – Not a fault necessarily, probably means the wine has been oxidised to some degree. This can give wine a slight Sherry or Madeira quality which is sought after with some wines such as White Rioja, Madeira & Tawny Port. – However……

Wine also has a smell of vinegar/acid – Wine has been over oxidised, could be because cork was dry, oxygen got into the bottle, could be during the production/fermentation process e.g.. Before the wine entered the bottle – This process is when Acetobacter (a bacteria) reacts with the alcohol and oxygen to produce Ethyl Acetate. – To complicate matters even more… Some winemakers actually look for this to enhance wine complexity.

Wine smells of wet dog, wet cardboard, musty & dank. This wine is faulty. – Wine has what is commonly known as cork taint caused by TCA or Trichloroanisole. Not just limited to cork in the bottle being at fault. This wine is truly “corked” the term is commonly used for several of these bad smelling faults but this is the true reason. – TCA can be caused by a fungi that grows in cork bark that taints the wine in a single bottle – Can also be found in oak barrels, cork bungs, oak beams, and processing lines in a winery these can affect an ENTIRE batch. Does not need a cork seal to occur. – Chlorine solutions that sterilise corks artificial or otherwise can also encourage TCA growth.

Wine has a slight whiff of egg, asparagus burnt rubber Not always a fault. – Wine bottles are nearly all washed with sulphur dioxide, nearly 95% of wines contain sulphites that preserve wines. Often this smell will disappear especially if decanted – If smell remains then it is correct to replace.

A non sparkling wine makes a fizz sound when opened and is effervescent in the glass – Wine has undergone a secondary fermentation – Residual sugar in wine has been fed on by yeast that has gotten into the bottle (perhaps unsanitary bottling) – However, some wines actively look for this frizzante quality such as Vinho Verde (Portugal) and some Gruner Veltliners

What appear to be sugar crystals are in the bottle or glass – Not a fault. This are Tartrate crystals, from Tartaric acid. They are harmless and occur naturally in grapes, they formulate in older wines or when wine gets too cold. – Would be fine to decant out or to leave as is, depending on customer preference.