Historically, what did placing a larva in mezcal bottles originally signify?

Answer

That the spirit was made from maguey (agave) instead of sugarcane ethanol.

The practice of inserting a worm, typically a moth larva, into bottles of mezcal or tequila was historically a measure of authenticity and quality assurance, not merely a modern gimmick, although it functions as marketing today. Centuries ago, when there was potential confusion or adulteration regarding the spirit's base ingredient, the presence of the worm served as a visible marker confirming that the liquor was derived from the *maguey* (agave) plant. This acted as a guarantee against spirits made using cheaper alternatives, such as sugarcane ethanol. While some specialized, high-end mezcal producers continue this tradition, it is generally not standard practice for the majority of mezcal producers and is seldom utilized with tequila.

Historically, what did placing a larva in mezcal bottles originally signify?
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