Fresh whites or reds, wines with beautiful acidity, which stand out for their great freshness... these are typical expressions of the world of sommeliers and wine enthusiasts. But what does it really mean and why is acidity so important in wine?
Wine is made mainly of water, alcohols and acids. Acidity (or freshness, which are synonymous) is an essential value in wine, which greatly affects the taste of the wine. Let's look at the concept in detail.
What is acidity in wine?
Acidity is one papillary sensation of "freshness" linked to the presence of acids, in fact.
Acidity (or gustatory freshness) is a sensation that belongs to the so-called hardness : it is that "snap" that gives character to the wine , contrasting harmoniously with the softer stimuli induced by alcohol and sugars.
How can you recognize acidity in wine?
The ideal is to start with whites and sparkling wines, where the acidity is more evident. It is recognized by the increase in salivation after swallowing the wine, together with the fresh, tasty and pleasant sensation it leaves in the mouth.
What effects do acids have on wine?
Acids have 3 main effects on wine:
- help determine the flavor ;
- are responsible for the feeling of freshness gustatory;
- they favor it conservation .
What acids are present in wine?
There are different types of acids present in wine: organic and inorganic , fixed and volatile , pre-fermentative and post-fermentative .
Type and quantity of acids present, pH and their penetration strength are the variables that determine the different sensations of acidity that we perceive in different wines.
Acids in wine: for further information
The numerous organic acids (tartaric, malic, citric, lactic, acetic, succinic are the main ones) have their own specific flavour.
There are three typical grape acids.
1. Tartaric acid it is the one present in greatest quantity (2-5 g/l) and defined as the "acidity backbone". Its flavor is harsh and a little sour.
2. Also malic acid it is no different (0-5 g/l), especially for its harshness. Very abundant in under-ripe fruit and in grapes grown in cold areas, the latter can be present in wine in very variable quantities. Sometimes it is completely negligible (especially if the wine has undergone malolactic fermentation ), while in other cases it can have a high concentration, which if excessive causes an unpleasant, unripe and "green" sensation. It is precisely malic acid that has the greatest impact from the point of view of the acidic flavor and the lowering of the pH.
3. Citric acid it is present in wine in very small quantities (0-0.5 g/l), while it is abundant in citrus fruits; It is recognized by its acidulous and citrine flavour, a little pungent.
Other acids are formed during the winemaking processes.
Lactic acid it is a product of malolactic fermentation and can be present in very variable quantities (1-3 g/l), inversely proportional to that of malic acid. Its taste is decidedly more pleasant and rounded than that of other acids: this is why it is defined as the sweet acid of wine.
Also acetic acid it is formed during alcoholic fermentation, but it is to be hoped that this is conducted correctly, so that its quantity is very reduced, because it is acrid and pungent. If it does not exceed the value of 0.2-0.5 g/l, the situation can be judged normal, but if due to accidental fermentations carried out by acetic bacteria a higher value is reached, we end up talking about a wine that tastes of vinegar , which is unacceptable.
The pH of wine
pH is a scale of measurement of the acidity of a solution. All acids have H+ ions that can dissociate: depending on the greater or lesser capacity to release these ions in an aqueous solution, acids are defined as strong or weak.
The pH of wine varies from 3 (typical value of cold climates or grapes harvested immature) to 3.8 (typical value of hot climates, of grapes harvested overripe or which have undergone malolactic fermentation). It does not have a limit at EU level because it varies with grape variety, climate, vintage and processing.
Acid penetration strength
Acids also have an important property on a sensorial level for those who taste wine: the force of penetration, i.e. the "charge" that is impressed on the taste buds. Among the acids present in wine, the maximum penetration force is that of acetic acid, which despite its small percentage contributes to significantly accentuating the sensation of acidity.
- Read also: how to taste wine
Acidity levels in the wine lexicon
Let's see how sommeliers speak, who measure acidity based on an intensity scale. These are conventions used in professional tasting, whereby a wine is defined:
- Flat or skinny : if you do not perceive any gustatory freshness, precisely due to the lack of acidity. It's a flaw and is generally found in old wines or wines affected by pathologies (for example the refermentation of some acids).
- Not very fresh : if you perceive a delicate sensation of acidity, which leads to very light salivation. Typically it is particularly evolved wines , in which this represents a normal situation.
- Fairly fresh : if you perceive a pleasant sensation of acidity, which causes good salivation, a prerogative of many wines with good evolution .
- Fresh : if you perceive a strong sensation of acidity, which causes abundant salivation, an important prerogative in young wines .
- Acidulous or unripe : if you feel a strong and predominant sensation of acidity, which causes abundant salivation as well as a slight gum contraction. These are wines obtained from under-ripe grapes or from vines that have a strong acidity. It can be one typical situation of very few wines , such as some Austrian whites from Styria. If not, it's a wine defect .
- Read also: tricks to speak like a sommelier
What should you pair wines with good acidity with? Three ideas
1. The acidic tendency of the wine offers excellent pairing possibilities. It balances perfectly with the sweet trend of food , because the contrast balances and gives beautiful sensations in the mouth.
2. Furthermore, a very important ability of the acidic tendency is to cleanse the mouth: therefore a wine with a strong acidity can be combined with red meats and slightly fatty cheeses .
3. If, however, the dish has strong acidity, it must be paired with a soft wine , where the degree of acidity will be lower, in order to prevent the sensations of hardness of the wine and food from adding together with an unpleasant effect.