Wine turns sour

Chinese people are accustomed to drinking white wine, and white wine culture is also a very important part of Chinese traditional culture. Wine is a type of alcohol that originated from Western countries. It is popular among many people for its refreshing and mellow taste. Drinking wine can beautify the skin, calm the nerves and calm the mind, so it is also very suitable for women. So is it normal to find that the taste of wine is sour when drinking it?

There is also acidity in the taste of wine. Acidity is an important component of the taste of wine. It generally includes: tartaric acid, malic acid, citric acid in the grapes themselves, and lactic acid and acetic acid produced in the brewing process.

tartaric acid

Tartaric acid is the "wine diamond" that we occasionally see on the wall, cork or bottom of the wine bottle. It is an organic acid present in wine and is one of the sources of wine acidity. Generally speaking, when the storage temperature of wine drops rapidly below 0°C, tartaric acid will easily form crystals.

In white wine, tartaric acid appears as colorless crystals. In red wine, tartaric acid appears as purple-red crystals. Tartaric acid comes from the grapes themselves, so tartaric acid crystals are harmless to wine and will not affect the quality of wine.

Malate Lactic Acid

Malic acid is found in many fruits, including our wine grapes. It exists in wine in smaller proportions than tartaric acid and often works together with lactic acid in a process called "malolactic fermentation" or "secondary fermentation."

Malolactic fermentation is followed by lactic acid fermentation, which converts the sharp malic acid into softer lactic acid, softening or reducing the acidity of the wine.

Citric acid

Citric acid is generally found in small amounts in grapes, but winemakers sometimes use it to add acidity to wine or to develop a particular flavor.

Having talked about the source of acid, we also need to know that “high acidity” in wine does not mean “tastes very sour”. Generally speaking, a good wine not only has sufficient acidity, but also has matching aroma and sweetness. So when the wine enters your mouth, you feel it is just right, sweet and sour, making your teeth soften without you noticing.

How important is sourness?

1. Acid is the "skeleton" of wine

Wine without bones is like a person without spirit. Approaching him will make you feel dull and tired. For wine, we call it loose quality, which makes people have no desire to continue drinking. Acidity, sweetness, tannins, aroma, etc. complement each other in wine, and acidity also makes the aroma clearer and the wine more vibrant.

However, it should be noted that excessive acid can also cause the wine to become sour, astringent, and have a reduced aroma. It’s all about balance.

2. The impact of acid on wine aging

Generally, we always think that tannin is the most critical factor affecting wine aging. In fact, high acidity, high sugar and high alcohol content also affect wine aging.

From the perspective of acid, generally speaking, the higher the acidity of the wine, the slower the oxidation process will be, and it will also help inhibit the growth of harmful microorganisms.

3. The relationship between acidity and food

For foodies, food that is too sweet or too greasy usually affects our appetite. It’s different with acid. The acid in wine can neutralize overly sweet and greasy foods, making them fresh and easier to eat.

Common causes of high acidity include:

1. Wine grapes grow where there is sufficient sunlight, usually far from the equator or where the vineyard is at a high altitude.

2. Wine grapes are picked before they are fully ripe, so they are not sweet enough and have high acidity.

3. Winemakers add fermenting grape juice to the wine during the winemaking process.

Note: Everyone has different tolerance to acid. For example, some people like sour food and have a higher tolerance to acid.