As an expert sommelier and brewer, I have encountered and tasted a wide variety of spirits, including tequila. While there are many different types and varieties of tequila, I have yet to come across a blue-colored tequila in my experience.
Tequila is traditionally made from the blue agave plant, which gives it its distinct flavor and character. The agave plants are harvested, cooked, and then fermented to produce tequila. During the production process, the color of tequila can vary depending on how long it is aged. Blanco or silver tequila is typically unaged or aged for a short period, resulting in a clear or slightly golden hue. Reposado tequila is aged for a minimum of two months, while añejo tequila is aged for at least one year. These aging processes can give tequila a deeper, amber color.
However, it is important to note that the color of tequila primarily comes from the aging process in oak barrels, rather than any artificial coloring. The use of artificial colors to create a blue-colored tequila would be highly unusual and not in line with traditional production methods.
That being said, there are some tequila brands that offer flavored variations of their spirits, such as lime or strawberry-infused tequilas. These flavored tequilas may have a hint of color depending on the ingredients used, but they do not typically have a blue color.
In my personal experience, I have not encountered a blue-colored tequila. I have tasted a wide range of tequilas, from blanco to extra añejo, and have always found them to be within the spectrum of clear to amber hues. The focus in tequila production is usually on the flavor profile and quality of the spirit, rather than its color.
While there are various colors and shades of tequila depending on the aging process, I have not come across a blue-colored tequila in my experience as a sommelier and brewer. The natural colors of tequila range from clear to amber, and any artificially colored tequila would be considered unusual and not reflective of traditional tequila production methods.