Information from "Guide to Tequila," by Kretchmer.
Blanco Tequila (Type I)
Tequila in its pure form is "blanco" or "white" tequila. Sometimes this
product is also referred to as "silver" or the Spanish" "plata." There is
absolutely no difference in the products carrying these different names, but
rather in the case of this category, more than anything else, the different
names reflect each producer's own marketing preferences. Legally, a blanco
tequila is any tequila that has not been aged for at least 60 days. In fact,
almost all producers will store the tequila in only stainless steel tanks, as
opposed to wooden barrels, for a short period of time before bottling them.
There are a few exceptions, and in those cases, the tequila gets only very
brief storage time in large wooden barrels. This process prevents little if
any flavor from transferring from the holding tanks into the tequila, thus
creating the purest product.
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Reposado Tequila (Type III)
By law, a reposado tequila must be aged in wood for at least sixty days. They
are almost always aged for less than one year. Sometimes this aging is done
in very large wooden storage tanks, which can range in size anywhere from
10,000 to 30,000 liters, but in some cases, small oak barrels are used.
Depending on a particular producers style the aging period of a reposado
typically ranges anywhere from two months to nine months.
A very popular drink in Mexico is based on a mix of reposado tequila with
grapefruit soda. The same flavor differences that are noticed when drinking a
reposado straight will carry over into their use in mixed drinks.
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Anejo tequila (Type IV)
According to Mexican law, an Anejo tequila must be aged for a minimum of one
year and it must be aged in government-sealed barrels that are no larger than
600 liters. While one year is the legally required minimum aging time,
anywhere from one to three years, depending on the particular distillery, may
be common. Typically, the barrels used are old 190-liter whiskey barrels from
Kentucky.
Anejo tequilas are used in "Prickly Pear Margaritas" to give the cocktail a
desired balance and smoothness.
Like blancos and reposados, anejo tequilas may be either 100 percent agave or
mixed.
"Muy anejo" is a product, which is "very aged." If a anejo has been aged for
more than one year than the bottles will state how many years it was aged.
This gets even more complicated because producers are aging the tequilas in
different type woods. But they are all officially categorized as anejos.
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Joven Abocado (Gold Tequila Type II)
Gold or joven (young) tequila is an unaged or blanco tequila to which additive
colors and flavors are mixed in after the distillation process. In order for
the tequila to take on a color by some other means other than aging in wood,
it must be through the addition of coloring. This is most often done by
adding caramel. The object is to simulate the effects that aging would have
had on the product, had the tequila actually spent time in a barrel.
The intent
1. The additives take away some of the harshness typically associated with
unaged tequilas.
2. Time is money. The addition of flavorings and colorings is far less
expensive than the cost of actually aging the product in oak barrels, to say
nothing of the extremely high cost of the barrels themselves.
Gold tequila is mostly produced for the export market.
Joven Abocado or "gold" category of tequilas, which are almost always,
produced as mixed tequilas. Today more than half the tequila exported is
joven abocado or gold tequila.