We further know from historical accounts that this was not always the case and other cereals were used such oats and possibly maize may have been used? However there has always been a slight cloud over this as no one could point out and say there you go it says in such and such that bla de bla used this ratio to make their PPS.
Due to lack of concert proof People have always surmised at what the ratios were but we never seemed to come up with anything substantial.
I've been reading a short titled book called "A Philosophical and Statistical History of the Inventions and Customs of Ancient and Modern Nations in the Manufacture and use of Inebriating Liquors" by Samuel Morewood published 1838 (Phew that was a mouth full) . The section on the Irish Industry covers Irish whiskey fairly extensively. A lot of historical accounting of the ancient progression of brewing through to Distillation but I have yet to finish this sometimes meandering book. However I have come across a golden nugget of a piece of information which I thought ye all maybe interested .... (I also came across some out put figures which show Irish Whiskey output to totally dominate and dwarf Scotch output in the early 1800's... but that's another story)
In a previous chapter the author gives a decent account of Mr James Jameson's working in Marrowbone Lane and concentrates on industrial apparatus and input & output figures but nothing majorly in regard to the actual whiskey or it's make up. Next chapter is about another Distillery however un-named but obviously a big opperation too.
"In one of the large concerns in the city of Dublin, the capacity of the stills .... In one brewing period 15,290 bushels of malted and unmalted corn are mashed producing 262,747 Gallons of wash ...."
This does not really tell us anything and as the author was more interested in profit margins from cost of production I just expected a rough estimation of costs.
He did a break down of raw material costs including coal etc to give a total of expenditure.
I did not expect to find what I saw next and got mildly excited about it and opened up a new Redbreast 15yo in celebration .
Mmmmmm
Sorry back to my exciting find, at the very top of the break down.
Allowing 1/7 for malt 2184bushels at 6s 3d Per Bush
......... 3/7 for barley 6553 ....... at 3s 4.5d ... ....
......... 3/7 for oats 6553 ....... at 2s 7.5d ... ....
Which adds up to the 15,290 bushels previously mentioned.
And is obviously an indication of an exact ratio of 1 Part Malt Barley to 3 Parts Barley to 3 Parts Oats
This is the clearest indication of a ratio of a real old style PPS I have ever to come across and to be honest I cannot imagine it to be anything like we have today. However this is not to say it was an industry standard either.
We can see from the above that there was substantial costs associated to Malted barley and why the practice of mixing the mash with cheaper grain would of been enticing and thus creating the wonderful creation of PPS.
What say ye ....
Any other spots on this line let us all know ... keep up the search