One of the documents I was most interested in laying my hands on at
thr Scottish Brewing Archive was something called "Majority Ale
Brewing a beer on the birth of an heir was a long tradition amongst domestic brewers. The beer would be carefully stored away and only broached when the child reached majority at age 21.
I thought that the practice had died out along with domestic brewing at the end of the 19th century. But William Younger continued to brew Majority Ales for members of the family not just in the 19th century, but right up until 1960.
Much like domestic brewers, William Younger brewed a very high gravity beer – between 1120º and 1150º - which they racked into casks and then stored away carefully. When the lucky child’s 21st birthday rolled around, some of the beer was bottled. The remainder was either racked into a smaller cask or used to fill up another cask of the same brew.
They kept a really close eye on each cask, a notebook keeping track of each one: when it was brewed, when beer was drawn off and bottled. Looking at this document, it becomes clear that they didn’t keep each brew totally separate. Sometimes they would fill up a cask with beer from an older brew. This way, I suppose, they could guarantee that the beer would be at least 21 years old when consumed.
They hung onto bottles for many, many decades. A stock list from 1967 includes Majority Ales brewed in 1866, 1895, 1897 and 1898. In all, they still had bottles of sixteen vintages of Majority Ale.