How much do you know about wine?

With the continuous development of society, people's material needs have further increased, and their pursuit of a quality of life is gradually moving towards the high-end. For the traditional drinking culture, it is not limited to Baijiu. In recent years, people are more interested in wine. So, how much do you know about wine? What is dry red? Is it true that the sweeter the wine, the better? The higher the alcohol content, the better? What are the main indicators that affect wine quality? Next, please join me in understanding common knowledge about wine.

What wine? Wine is a product made from fresh grapes or grape juice that has been fully or partially fermented. The basic principle is that the sugar in grape fruits is converted into alcohol and carbon dioxide gas by the fermentation of brewing yeast, while producing aroma substances and releasing heat, resulting in wine containing alcohol. Therefore, it can be seen that wine is a type of fruit wine; The raw material for wine must be grapes or grape juice, and wine has a certain amount of sugar; The fermentation process produces alcohol, which is the alcohol content indicated on the wine label.

What are the main indicators that affect the quality of wine? There are mainly sensory requirements, as well as physical and chemical requirements such as alcohol content, total sugar, dry extracts, volatile acids, and carbon dioxide.

Sensory requirements: White wine should be approximately colorless, slightly yellow with green, light yellow or golden yellow, red wine should be purple red, deep red, ruby red, red with a hint of brown or brownish red, and peach wine should be peach red, light rose red or light red. Wine should be clear and glossy, without obvious suspended solids, and wines exceeding 1 are allowed to have a small amount of sediment. Sparkling wine should be infused into the glass with fine bead like bubbles that rise and have a certain degree of persistence. According to the sensory evaluation of wine, it can be classified into excellent, excellent, qualified, unqualified, and inferior grades. Of course, when making a purchase, consider high-quality products as a provincial choice. Premium wines should have the necessary luster, natural, pleasing to the eye, clear, and glossy; It has a pure and rich, elegant and harmonious fruity aroma, with a delicate and smooth taste, a full and complete body, and a long and pleasant aftertaste.

Alcohol content: China stipulates that the alcohol content of wine should not be less than 7%. That is to say, one liter of wine contains more than 70 milliliters of alcohol.

Total sugar: refers to the total amount of various sugars in wine, including glucose, fructose, lactose, sucrose, etc. It is calculated by converting to glucose.

Dry extract: All soluble substances in wine, excluding alcohol, sulfur dioxide, carbon dioxide, and low volatile substances, are called total extract. Dry extract, also known as sugar free extract, is the total amount of non-volatile substances in wine under certain physical conditions, including free acids and salts, tannins, pigments, pectin, low sugar, minerals, etc. Simply put, dry extract is the sum of other substances that remove sugars from the total extract. Dry extract is an important indicator for evaluating the quality of wine, which is an important basis for determining whether wine is pure brewed and whether there is blending. It is also one of the important indicators reflecting the quality of wine.

Volatile acid: As the name suggests, volatile acid refers to the volatile acidic substances in wine, generally related to spoiled grape fruits, unhygienic brewing processes, and containers. Excessive volatile acids can cause changes in the sense of smell. According to national regulations, the content of volatile acids in wine cannot exceed 1.2 grams per liter.

Carbon dioxide: At the end of wine fermentation, the winemaker will transfer the fermentation broth to a high-pressure sealed container for fermentation, creating a very high pressure for the carbon dioxide gas produced during fermentation. Under high pressure conditions, the carbon dioxide gas will dissolve in the liquor, resulting in sparkling wine with bubbles.

How is wine classified?

If classified by the color of wine, it can be divided into white wine, ros é wine, and red wine.

1. White wine is fermented from white grapes or grapes with red skin and white flesh. The requirement for dry extract is greater than 16 grams per liter.

2. Peach red wine is made by fermenting colored grapes with skins. The requirement for dry extract is greater than 17 grams per liter.

3. Red wine is made by fermenting grapes with red skin, white flesh, or even red skin and flesh. The requirement for dry extract is greater than 18 grams per liter.

If classified by the sugar content of wine, it can be divided into dry wine, semi dry wine, semi sweet wine, and sweet wine. The sugar content of wine refers to the amount of total sugar converted into glucose per liter of wine.

1. Dry wine. If the sugar content is below 4 grams/liter, there is no sweet taste.

2. Semi dry wine. The sugar content ranges from 4.1 to 12 grams per liter, with a slightly sweet taste when tasted.

3. Semi sweet wine. The sugar content ranges from 12.1-45 grams per liter, with a slightly sweet taste when tasted.

4. Sweet wine: With a sugar content greater than 45 grams per liter, it has a sweet taste when tasted.

If classified by the carbon dioxide content in wine, it can be divided into calm wine and sparkling wine.

1. Calm wine. Wine that does not contain self fermentation or artificially added carbon dioxide. Calm wine has a carbon dioxide pressure of less than 0.5 kilograms per square centimeter at 20 degrees Celsius.

2. Sparkling wine. Adding sugar to wine and fermenting it will produce carbon dioxide, and the pressure of this type of wine is greater than 0.5 kilograms per square centimeter. It can be divided into two types: high foam and low foam.

(1) High sparkling wine: This type of wine can naturally ferment to produce carbon dioxide pressure exceeding 3.5 kilograms per centimeter. High sparkling wine can be divided into natural high sparkling wine (with a sugar content of less than 12 g/L), dry high sparkling wine (with a sugar content between 12.1-17 g/L), dry high sparkling wine (with a sugar content between 17.1-32 g/L), semi dry high sparkling wine (with a sugar content between 32.1-50 g/L), and sweet high sparkling wine (with a sugar content above 50.1 g/L) according to its different sugar content.

(2) Low sparkling wine: This type of wine produces carbon dioxide pressure ranging from 0.5 to 3.4 kilograms per centimeter through natural fermentation.

What is tannin? Chemically speaking, tannins are actually tannic acid, which is a natural phenolic substance. Simply put, tannins are acidic substances. When we taste wine, we often feel astringency, which is actually the tannins in wine. The presence of tannins determines the flavor, structure, and texture of wine. The content and quality of tannins are one of the important factors for evaluating the quality of wine, with the majority being in red wine, which can be said to be the soul of red wine. Tannins mainly come from grape skins, grape seeds, grape pulp, and grape stems. During the brewing process, oak barrels also bring certain tannin substances to the wine. Therefore, red wine blended with skin and flesh has much higher tannins than white wine fermented without skin. The presence of tannins is one of the most important differences between red wine and white wine.

Why do we need to sober up? Before drinking wine, it is generally necessary to sober up. The purpose of sobering up is to remove sediment from wine, remove sulfur dioxide from wine, and allow wine to fully come into contact with air, undergo oxidation, and make the wine smoother to drink.

What is the function of the groove at the bottom of a wine bottle? In fact, the groove at the bottom of a wine bottle has nothing to do with the quality of the wine. Its main function is to make the bottle more stable when held, allowing the bottle to be placed more steadily, facilitating the sedimentation of some sediment, facilitating stacking, and enhancing pressure resistance. Most wine bottles have a groove at the bottom.

How should wine be stored? When storing and transporting wine sealed with cork, attention should be paid to placing it upside down or horizontally, avoiding strong vibrations, freezing, and exposure to sunlight. The transportation temperature should be maintained at 5-35 degrees Celsius, and the storage temperature should be maintained at 5-25 degrees Celsius.