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
The age statement on the rum is based upon certification in the United Kingdom (I note that the UK customs system is very stringent). Unfortunately there is no record of when the rum was shipped from Guyana to the UK, but my speculation is that it was probably meant to be part of the blend of a ‘navy style’ rum as Port Mourant Rum (from the Double Wooden Still) is one of the key ingredients in those British Navy Rums.
The Year Old Special Reserve Rum is blended from aged stocks (the youngest being no less than 12 years old) from the original Wooden Enmore Coffey still, the original metal Diamond Coffey still, as well as from the ancient Port Mourant double wooden pot still which was used to produce ‘navy’ rum for the English Admiralty. All of the Demerara Rum produced by El Dorado is aged exclusively in American oak (bourbon barrels).
Although Juan Santos is relatively unknown outside of the Western Canadian market I have discovered that these rum brings an astounding level of smoothness and depth to the rum glass.
The Rum Nation Caroni 1998 is one such offering from the folks at 
The Rum Howler Blog 