The following methods are used to identify the authenticity of Gu 20:

1. Identification of outer packaging and bottle stickers: The bottle sticker of genuine wine is a fully registered trademark, and the one used is "Gujing Gong" Registered trademark. The registered trademark pattern is circular, with a locust tree on the left, an ancient well under the tree on the right, and blue sky and white clouds on the top.

2. Seal identification: The seal of real wine is a yellow aluminum fracture cover, which is smooth and round, with the ancient well pattern and the words "registered trademark" printed on it. Counterfeit wines are also sold in real bottles, but the caps are usually broken and the seals are not neat.

3. Wine quality identification: The real wine has the characteristics of clear and transparent color, no overflowing when the cup is full, rich cellar aroma, sweet and clean, while the fake wine has a mixed body, floating impurities, and a spicy, bitter taste. , some also contain large amounts of lead, methanol and other harmful substances.