I figured I was safe buying "100% agave" tequila.
Turns out there's a loophole.
Here's what else is in your "100% agave" tequila:
Glycerin — thickens mouthfeel, hides rough edges
Caramel coloring — makes it look aged without actual aging
Oak extract — fakes barrel character
Sugar syrup (jarabe) — adds sweetness
Before 1997, the total limit was 1% by weight across all four. Then the wording shifted to allow 1% of each.
The TTB allows 96% agave tequila to be called 100% agave. Nothing else has to appear on the label.
"The [TTB] told you to reject the evidence of your eyes and ears. It was their final, most essential command." - George Orwell
The one bright spot: as of 2013, blanco tequilas cannot contain any additives at all. Only water can be added after distillation. This is what I stick to when I'm taking a break from wine.

Turns out there's a loophole.
Here's what else is in your "100% agave" tequila:
Glycerin — thickens mouthfeel, hides rough edges
Caramel coloring — makes it look aged without actual aging
Oak extract — fakes barrel character
Sugar syrup (jarabe) — adds sweetness
Before 1997, the total limit was 1% by weight across all four. Then the wording shifted to allow 1% of each.
The TTB allows 96% agave tequila to be called 100% agave. Nothing else has to appear on the label.
"The [TTB] told you to reject the evidence of your eyes and ears. It was their final, most essential command." - George Orwell
The one bright spot: as of 2013, blanco tequilas cannot contain any additives at all. Only water can be added after distillation. This is what I stick to when I'm taking a break from wine.

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