Liquor, also known as shochu or huojiu, is one of the seven distilled spirits in the world. It has its unique technology, style and excellent color, fragrance and taste, and occupies an important position in the food industry and the whole national economy. With the comprehensive integration of China's economy and the world economy, wine, as an essential beverage, will surely enter the world market. The biggest feature of foreign liquor varieties is low alcohol content. If China liquor wants to go to the world on a larger scale, it must develop to low alcohol content to adapt to foreign drinking habits. At the same time, for China with a population of over one billion, the development of low-alcohol liquor can also save a lot of food, which is in line with the national industrial policy and has great social and economic benefits. 1. Flavor components and styles of liquor The style of liquor is a comprehensive feeling of harmonious balance between aroma and taste of liquor, which is directly related to its main flavor components. The main components in liquor are ethanol and water, accounting for about 98% of the total weight, while the flavor components only account for about 2%, which determines the aroma, flavor type and style of liquor. It constitutes the different typicality of liquor. Acid: it is the main substance to form the flavor of liquor and the necessary condition to form ester. Without acid, there is no ester. The main organic acids in liquor are acetic acid, caproic acid, lactic acid and butyric acid, and their sum accounts for 90% ~ 98% of the total acids. Ester: Volatile compound with aromatic smell, which is the main flavor component in liquor, plays a decisive and key role in the typical formation of various liquors. Alcohol: It also plays an important role in liquor. It is the main substance of alcohol sweetness and aroma AIDS in liquor, and also the precursor of aroma substances. Alcohol and acid react to form various esters, thus forming the special aroma of liquor. Carbonyl compounds: it is very important to form the main aroma of liquor, and the aroma of liquor is closely related to the content and types of aldehyde compounds. Aromatic compounds, nitrogen-containing compounds and furan compounds also play an important role in liquor. In addition, the aroma characteristics of sulfur-containing compounds, ethers and other compounds need further study. 2. The position and function of flavor components in liquor is the material basis of food flavor, and the flavor formation of liquor is also inseparable from its flavor components. Besides water and ethanol, liquor also contains hundreds of organic and inorganic components, each of which has its own characteristics. They are mixed in a system, which influences each other and restricts the flavor of liquor. Wang Zhongyan et al. divided other components except ethanol and water into chromatographic skeleton components and trace components according to the content of aroma components. Chromatographic skeleton components are components with mass content greater than1mg/100 ml ~ 2 mg/100 ml, which belong to the conventional quantitative analysis index of liquor chromatography and are the main components of China liquor, and their existence determines the flavor type and liquor quality of China liquor. Trace components, that is, non-chromatographic skeleton components, are highly volatile and have extremely low content in liquor. Their large quantity and complex sources bring difficulties to the study of liquor, and the study of trace components is of far-reaching significance to the development of liquor quality. 3. Development trend of low-alcohol liquor With the gradual improvement of economic and cultural level, people's drinking habits are quietly changing, and the pursuit of liquor taste is also weakening from strong to weak. After China's entry into WTO, the tariff of liquor was lowered, which led to a large influx of foreign wines such as whisky with much lower price. Most of the internationally popular liquors were around 40%vol, which could be drunk with ice and carbonated water, with higher quality, which had a certain impact on China liquor. Facing the impact of China's entry into WTO on liquor industry, we should look at the changes and development of China liquor in the past 50 years from two aspects. On the one hand, the quantity and quality of liquor production in China have taken a big step forward in the past 50 years; On the other hand, China liquor industry is in a new transition period. Judging from people's drinking habits, in recent years, 38% vol ~ 45% vol medium-low alcohol liquor has become a star in the market. Since all countries in the world generally classify alcoholic beverages with a volume of more than 40% as spirits and impose high tariffs, in order to open the world market after China's entry into WTO, the domestic liquor industry should focus on developing low-alcohol liquors with a volume of less than 40%.