Once the leaves have been chopped off, the heart of the blue agave, called the pina, is what is used to make tequila.[Photo by Maxime Lu/China Daily]

A margarita at Q Mex costs 55 yuan ($8.50) and a shot of standard tequila 25 yuan. A shot of a higher-quality brand will set you back 50 yuan.

"Top-quality tequila is extremely smooth, and it comes as a surprise to Chinese, indeed anyone, who tries if for the first time. It can be much smoother than whiskeys or brandies.

"Of course, there is the cocktail, which tequila is great at, and then there is the shot, which is becoming very popular among Chinese, especially this ritual where people drink tequila with a little lick of salt and then suck a lime slice."

Roberto Anaya Moreno, general director of the CNIT, says it hopes for tequila exports to China to grow 10 percent next year.

Nacho Del Toro, project manager of tequila from Thirsty Work Productions, the official agency that developed the marketing campaign for tequila in China in 2015, says there are around 43 brands on the Chinese market now.

Some of the most popular are Patron, Jose Cuervo, Olmeca, Fogata, Don Julio and El Charro.

"The thing about tequila is that there are many different ways it can get to consumers," Del Toro says. "You can reach different people with different classes of drink. You can drink tequila straight, in cocktails, and paired with food or cigars, and many different ways."

Mexican Official Norm classes tequila into two categories: the 100 percent blue agave, and mixto, using at least 51 percent agave, with the rest coming from other sugars.

Each of those two categories can be broken down into five subclasses: blanco, joven, reposado, anejo and extra anejo. The most common tequila is blanco, which is bottled immediately after it is distilled.

Reposado is aged tequila that has been rested in white oak barrels for between two months and a year. Anejo is tequila aged in casks for more than a year. Extra anejo will have been aged for three years, and is the top class.

Joven is a blend of blanco and reposado or blanco and anejo.