Ron Zacapa rums are made from sugar cane harvested in southern Guatemala, which is pressed into virgin sugar cane honey. The fermentation process uses a yeast strain (saccharomyces cerevisae) isolated from pineapples to transform sugars within the ‘honey’ into alcohol. This fermentation process takes approximately 5 days after which the fermented ‘wine’ is distilled in a single continuous column.
After distillation, the Zacapa rum is transported to the ‘House above the Clouds’ in the Guatemalan mountains for maturation. Special cellars age the rum at an altitude of more than 7000 feet above sea level where the ambient temperature is much more stable and the oxygen levels are lower than at lower elevations. The more stable ambient temperature ensures that the aging barrels are subject to less differential air pressure between the outside and the inside of the barrel.
I should note that this version of Ron Zacapa Centrenario is an older vintage from the one currently available for sale. This version is labeled 23 anos rather than 23 solero. The older vintage received a higher score when I reviewed it, and when I tasted it side by side with the newer version, I found that I indeed preferred slightly drier and less sweet flavour.
Here is a link to the review of the #4o spirit on my Rum Howler Top 100 Spirits Countdown.
#40 Ron Zacapa Centrenario 23 Anos
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You may follow my Countdown list of the 100 Best Spirits here: The Rum Howler 2015 – Top 100 Spirits
Here is a link to my review of the #73 entry in my 
Just so we are clear, there may be additional benefits gained by resting a spirit in airtight vats; however, it is widely accepted that no further maturation of the spirit occurs in an airtight container. Pumpkin Face 23 is (according to the information provided) a 23 Year Old Rum based upon how long it was resting in oak barrels; the 10 years the rum spent in the stainless steel vats are not included in the age statement.
A unique feature of the Dictador Solera System is that in addition to the younger rums being married with older rums, the barrels of similarly aged rums along one level of the solera are periodically consolidated to keep the barrels as full as possible to maintain fuller contact with the wood, and to inhibit the acceleration of the evaporation within the barrels. The Dictador 12 Year Old Rum, is a solera aged rum which is taken from the solera at the point where the average of the rum within that solera row is at least 12 years of age.
This is a true Solera rum with 4 rows of aging barrels set one atop each other. As the rum ages, a portion of the rum moves through each row until it reaches the final solera row at the bottom years later. The barrels are not emptied fully and only a portion of the rum from the previous or higher row is moved to the lower row each time. According to the Santa Theresa website, a very small portion of the rum reaches an age approximating 25 years before bottling.
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