Needless to deny, when the wine tastes like vinegar, it is sick and impossible to appreciate! Well, yes, even a bottle of wine can get ill and deteriorate so much that it smell of vinegar in this case: a fantastic product if used correctly in the kitchen but, undoubtedly, a terrible olfactory and gustatory scent when it comes to wine.
Acescence ( the process that converts wine into vinegar ) is easy to find, but to dispel doubts, let’s see how you can recognize it.
Wine tastes like vinegar for one main reason: it has been attacked by two aerobic microorganisms belonging to the family of acetic bacteria.
The first is the Acetobacter – microorganisms typically developing in fermenting musts and finished wines. In the presence of oxygen, they feed on ethyl alcohol, oxidizing it and transforming it into acetic acid, acetaldehyde, ethyl acetate, and water.
The second one is the Gluconobacter – microorganisms that already act on the grapes when they are damaged and affected by mold and also in the must. In the presence of oxygen, they feed on the glucose in grapes and musts, transforming it into gluconic acid and acetic acid.
A certain quantity of acetic acid in wine at the end of the production process is regular but should never exceed 5 grams per liter. Beyond this limit, the volatile acidity is too annoying to make a wine seem vinegary.
Which Wines Are Most Affected by Acescence?
Fortunately, not all wines undergo acetic fermentation. The most affected are poorly structured reds, with slight acidity, and those with good residual sugar and low alcohol content, produced and stored in excessive temperatures, generally between 18° C and 34°C.
However, all those wines made with unhealthy grapes and in hygienically unsuitable environments are affected by acetic bacteria since they already contain the same microorganisms.
When does wine become vinegar?
The damage can occur during the wine production phase and afterward when the wine has already been purchased and, maybe, badly stored.
The determining factor in triggering the action of acetic bacteria is the air! It is no coincidence that these bacteria are aerobic. For this reason, correct cellar practices and optimal product conservation conditions are essential.
Often, the acescence occurs in excessively full aging barrels, where the wine has more and prolonged contact with oxygen.
How to prevent wine from becoming vinegar?
To block the possible attack of bacteria in the production phase, the grapes and the wine must be treated with the highest level of hygiene, checking the wholesomeness of the berries and carefully cleaning the production environments and the vinification and aging containers.
Furthermore, it is necessary to work with constant temperature control in ventilated environments, limiting the contact of the must and the wine with the air as much as possible. This is why carrying out frequent pumping, constant fillings of the aging containers, and rapid transfer and bottling practices are essential.
Today, these operations are increasingly more accessible, thanks to modern systems for transferring the must and for bottling.
How to recognize when the wine tastes like vinegar
Visual exam: A wine that tastes like vinegar can already be identified by sight thanks to a veiled appearance, such as when water is poured into a glass with soap or oily residues.
Olfactory examination: It is precisely on the olfactory analysis that a wine that tastes as vinegar manifests itself in all its horror. Impossible to avoid the smell of acrid and pungent aroma typical of vinegar due to the presence of the volatile molecule known as ethyl acetate. Annoying olfactory sensations that also recall the smell of particular solvents, such as acetone.
Gustatory examination: If there are still doubts, a wine that tastes like vinegar leaves no way out with every sip. It is difficult not to notice its watery consistency, devoid of structure, its complex, sour taste, with an acidic and bitter persistence at the same time … just the taste of acetic acid, in one word: undrinkable.