The manufacture of oak barrels is also very particular. First of all, the wood used for barrel making must be oak with a tree age of over 100 years. Oak is produced in many places in the world, including Inner Mongolia and three provinces in Northeast China. However, wine experts agree that the best quality of oak produced on Linmao mountain, about 150 km east of cognac, is the best for brandy storage. American white oak ranks second, but is far from the quality of French oak. However, the white oak produced in Arkansas is suitable for Scotch whisky. Secondly, when the oak tree is cut down, it must be dried for more than two years before it can be processed into barrels.
In the production, the oak can not be sawn, but must be split with an axe, so as to avoid damaging the original structure of the wood. The split wood should be dried for one year and left to the sun and rain to remove the bitterness. As for the production process of oak barrel, it is very similar to that of round wood in China. It is inlaid with oak boards one by one, without glue or iron nails. When making, first make one end of the barrel, hoop it with iron hoop, and then turn it upside down, and bake it in the middle of the barrel with fire. Using the principle of heat expansion and cold contraction, the other end is also rolled into a barrel shape. The boards should be assembled tightly, and then hooped with iron hoops outside. The exquisite craftsmanship is really amazing. A brandy barrel with a capacity of 350 liters is ideal. It is said that the contact area between liquor and wood is the most average. This oak barrel is worth $1000. The capacity of a whisky barrel is generally 200 liters.
The chemical substances in wood can be roughly divided into two categories: one is called cell wall material, including cellulose, hemicellulose and lignin; the other is non cellular material, which can be generally divided into mushroom, phenol, sugar, protein, alkaloid, oil and plant wax. When the wine is stored in the barrel, the air will enter the barrel through the oak cells to make the wine absorb oxygen, and the wine will emit steam through the oak barrel. At this time, the liquor will soak into the cell wall to absorb the components in the wood and improve the wine quality. Because the liquor will volatilize in the form of steam during the storage period, resulting in the loss of liquor liquor by 3 ^ - 5 per year. Therefore, the longer the liquor age is, the more expensive the wine price will be.
When we mention the aging of wine, we will inevitably associate it with the cellar of wine in the barrel. In fact, in order to improve the quality of wine, we should pay attention to other factors besides hoarding. Wine with good quality will get older and better, but the wine with poor quality will go to the opposite side. We should know that the quality of wine is not only related to grape variety, origin, soil, air, water, but also closely related to brewing technology and brewing technology.
After the fermentation of French Bordeaux red wine, it takes half a year for the new wine to be more perfect. Moreover, it needs to be stored in 225 liter oak barrels, while the oak is from Canada and matched with certain proportion of French Limousin oak. It can be seen that the aging of a good wine is determined by many factors. For example, the quality of Scotch whisky is not only related to brewing technology and experience, but also positively related to grain, peat, water quality, environment, distillation equipment, barrel material, barrel storage time and liquor store environment.
As we all know, chrysanthemum wine, including still wine or bubble wine, should be stored in the wine cellar, whether in barrels or bottles. The wine cellar must be located deep underground, and the temperature should be kept between 10-13'c. the humidity should also be small, usually maintained at about 75%. If the humidity is too high, both the bottle stopper and label will be rotten. If the air is too dry, the cork will shrink The liquor drips. At the same time, the wine storage place in the wine cellar must be kept in order, and inflammable or volatile substances shall not be piled up to avoid damaging the quality of wine
Although the oak barrel is beneficial to the improvement of the quality of some wines, it is not beneficial to the quality of all wines. For example, when people appreciate the fresh and fresh flavor of white wine, there is no need to store it in barrels; for vodka, gin and colorless cherry brandy, because their quality has been basically fixed when they are distilled out of the distiller, there is no need to store them in barrels. In addition, liquors with various colors do not need to be stored in barrels.