Rum Aging Science2
Series Overview
The January 2020 issue of “Got Rum?” covers in detail the goals of this series, as well as, descriptions of the different equipment being used to collect and measure the data.
March’s Weather
The month of March was considerably warmer than that of February. The humidity inside the cellar hit a minimum of 30% and a maximum of 95%, with an average of 82% for the month.
March's Weather
The temperature inside the cellar ranged from 52°F to 83°F, with an average of 67°F for the month.
The Rum
The change after 3 months in the barrel was not as drastic as it was after the first month.
Color: The color is almost identical to the naked eye as it was 30 days earlier. The spectrophotometer indicates it is a few shades darker.
Samples of each barrel
Aroma: The aroma is starting to develop a “cask” personality, but it is still rather weak and flat. There are hints of oak lactones and tannins, but the tannins are fresh, meaning they have not been oxidized (or reduced if you are a chemist) yet.
pH: The rum that went into the barrel had a pH of 7.04. This number is now 5.23. Please refer to the March issue for an explanation of why pH values are not linear.
ABV: The ABV remained the same as the previous month: 63.42%.
pH and Acidity
In last month’s issue we took a closer look a the pH scale used to measure the acidity in our rum. We explored the logarithmic nature of the scale, to make better sense of the non-linear nature of the readings we are collecting.
Did you know that there are different types of acidity or sources of acid in aged rum? Total Acidity or Titratable Acidity (TA) refer to the collective acids, which include volatile acids and non-volatile (or fixed) acids.
Acids are very common in all alcoholic beverages. In the world of wine, for example, lack of acidity results in “flat” wines. In the world of rum, acidity in the form of Acetic (Ethanoic) Acid is the most common, but many other carboxylic acids are present, each one contributing to the formation of specific aldehydes and esters.
Join us again next month, to continue our exploration of this fascinating topic!