In sensory identification of liquor, we should mainly focus on the determination and evaluation of the color, smell and taste of liquor. Attention should also be paid to identifying the outer packaging and registered trademark of bottled wine. When visually inspecting the color of liquor, we should first observe its transparency to the light, turn the bottle upside down, and check whether there are impurities sinking and suspended solids in the liquor, and then pour it into a beaker to observe its color on a white background. 2. Classification of wine varieties There are many kinds of wine, and there are generally four classifications. (1) According to the production characteristics, it can be divided into ① Distilled liquor: the liquor made by distillation after raw materials are fermented is called distilled liquor. This kind of liquor has little other solid content, high alcohol content and strong irritation, such as white wine and brandy. ② Fermented original wine (or pressed wine): the wine obtained by pressing after the raw materials are alcoholized and directly extracted. This kind of wine has a low degree of alcohol, but more solid content and less irritation, such as yellow wine, beer, fruit wine and so on. ③ Blended wine: It is made of white wine or edible alcohol and a certain proportion of sugar, spices and medicinal materials. This kind of wine has different sugar content, pigment, solid content and alcohol content due to different varieties, such as orange wine, bamboo leaf green, five tomato skins and various dew wine and medicinal liquor. (2) according to the alcohol content, ① high-alcohol liquor; Those with alcohol content above 4 degrees are highly alcoholic. Such as liquor, qu liquor, etc. ② Moderate liquor, where the alcohol content is between 2 and 4. Such as most blended wines. ③ Low-alcohol liquor: those with alcohol content below 2 are low-alcohol liquors, such as yellow rice wine, beer, fruit wine and wine. They are generally original juice wine, and the nutrients are retained in the wine liquid. (3) According to the production raw materials, ① Grain wine: wine brewed with sorghum, corn, barley, wheat and rice as raw materials. ② Non-grain wine: wine made from wild plants or fruits containing starch. (4) According to the flavor characteristics of wine, wine is divided into five categories: white wine, yellow wine, beer, fruit wine and mixed wine. 3. The basic method of sensory identification of liquor, also known as distilled liquor, is a colorless, transparent and high-alcohol beverage made from substances rich in starch or sugar as raw materials, adding koji yeast and other auxiliary materials, and saccharifying, fermenting and distilling. People attach great importance to the aroma and taste of liquor when drinking. At present, the evaluation of liquor quality is mainly based on sensory indicators, that is, from three aspects: color, aroma and taste. (1) Identification of color transparency The normal color of liquor should be colorless and transparent, with no suspended matter and sediment. Pour the white wine into the cup, and there shall be no ring-shaped insoluble matter on the wall of the cup. Turn the bottle upside down and observe the wine body in the light, without suspended matter, turbidity and precipitation. In winter, if there is precipitation in liquor, it can be heated to 3 ~ 4℃ in water bath, and if the precipitation disappears, it will be normal. (2) Aroma Identification In the sensory identification of the aroma of liquor, it is best to use a glass with a big belly and a small mouth, pour the liquor into the cup and shake it slightly, and immediately smell its aroma carefully with your nose near the mouth of the cup. Or pour a few drops of wine on the palm of your hand, rub it a few times, and then smell the palm of your hand, so that you can identify whether the intensity of the fragrance and the fragrance type are normal. The aroma of liquor can be divided into: overflowing aroma-the aroma or aroma components of liquor overflow in the air near the mouth of the cup, and the concentration and characteristics of aroma can be directly identified by smell. Perfume-when you drink wine, the aroma fills your mouth. Leave a fragrance-the wine has been swallowed, but the aroma of the wine still remains in the mouth. General liquor should have a certain fragrance, and there is little fragrance or fragrance. Wuliangye, a famous wine, is famous for its fragrance, while Moutai is famous for its fragrance. Liquor should not have peculiar smell, such as burnt smell, rotten smell, earthy smell, sugar smell, distiller's grains smell and other bad smells should not exist. (3) Taste identification The taste of liquor should be divided into strong, weak, soft, spicy, pure and evil, and after the wine is swallowed, it can be divided into sweet and bitter. The taste evaluation of liquor is mellow without peculiar smell and strong irritation. When the taste of liquor is identified by the senses, the liquor in the mouth should be carefully tasted in the tongue and throat to identify the mellow degree of liquor taste and the quality of liquor taste. (4) Alcohol discrimination The alcohol content of liquor is calculated by the percentage of alcohol content. All kinds of liquor are marked with alcohol degree on the factory label, such as 6', which means that the alcohol content of this liquor is 6%. The general characteristics of liquor are clear and transparent liquor, pure texture, rich aroma, long aftertaste and endless aftertaste. Factors affecting the quality of liquor: (1) Discoloration of liquor: When the liquor is kept in an iron drum without wax, the iron drum wall is easily oxidized and reduced to a compound with high iron ion or low iron ion, thus turning the liquor yellow-brown. The use of zinc-containing aluminum barrels will also lead to oxidation with acids in liquor to generate zinc oxide, which will turn the liquor into milky white. (2) The off-flavor of liquor: The liquor will be filled with cast iron (pig iron) containers, which will make the liquor produce the smell of sulfur. The wine stills coated with rotten blood materials will produce a bloody smell when they hold wine. Some wine boxes are filled with new wine in the process of flow and transportation, and odor pollution will also occur, which will make the wine with the bitter taste of wood. No matter whether it is discolored or stale liquor, the reasons should be found out, and the liquor that has been restored to its original quality after special treatment can continue to be drunk, otherwise it is not suitable for drinking or can only be used for other purposes.