This tangy new whisky packed more flavour than common wheat whisky and almost everyone preferred it. Customers started demanding "rye," wheat whisky with a small amount of rye grain added. Eventually, the word "rye" entered the Canadian lexicon as a synonym for whisky.
In the 20th century some Canadian distillers began using corn to make their whisky. Driving across the Ontario corn-belt today, you would never suspect that these hardy varieties of corn were not even developed until the 1950s. Before that, when corn was used for whisky-making it was imported from the U. S. But why corn? Quite simply, corn produces more alcohol than wheat does. By adding even a small amount of rye-grain whisky, distillers can still maintain distinct Canadian whisky flavour.
In the mid-20th century, whisky makers in the States decided that their "straight rye" had to be made from a mash of at least 51 per cent rye grain.
Some whisky fans took this to mean that Canadian rye, made with smaller amounts of rye grain, is not "real rye." But that makes no sense. Rye grown on the fringes of cultivation is spicier than that grown in more southerly climes.
Moreover, these American regulations arrived nearly 150 years after Canadians had already defined what rye whisky meant to them. In Canada, rye is a flavour and some of the same congeners derived from rye are also found in well-seasoned oak barrels.
There is another twist to the tale. In the U. S., distillers blend the grains before mashing them, in what they call a mash bill. In Canada distillers mash the individual grains separately then bring them together as new spirit or matured whisky. So, 51 per cent rye or not, today the concept of a mash bill is essentially meaningless in Canada.
There's more: when corn is fermented it produces large amounts of alcohol, 14 per cent alcohol is the norm in a corn mash but often it goes higher.
Rye on the other hand produces in the range of eight per cent alcohol, often less than that. So a mash of 51 per cent rye and 49 per cent corn is still producing a lot more corn whisky than it is rye. Thus, Canadian distillers who blend at the liquid stage rather than as dry grain get proportionally more impact from the rye grain they use.
In the U. S. "straight" whisky must be aged in brand new charred oak barrels. These barrels are so loaded with flavours of their own that they can overpower the influence of the grain. Even though rye grain is spicy and rich in flavour, American distillers use a high percentage of rye to ensure that its natural flavours can survive the burst of oak flavours from inside the barrel.
In Canada, though, rye whisky is aged in a mixture of barrels that have already been used one or more times, as well as in new ones. Re-used barrels bring additional flavours to the whisky that are not detectable in whisky that has been aged in new oak. Some of these flavours taste like rye. As the oak flavours are more subtle overall in reused barrels, it takes a relatively smaller amount of rye grain to get a great surge of flavour.
Today, as micro-distilleries spring up across Canada, many hope to revive the "tradition" of all-rye Canadian whisky.
But it's a tradition that exists more in the imagination than in reality. Canada's early settlers grew rye grain as a stopgap, because they knew that it thrived in poorly cultivated, recently broken soil. But as soon as rough land became tilled fields, farmers switched from rye to more bountiful wheat, and distillers stopped using rye grain, except in small amounts for flavouring.
So is Canadian whisky really "rye"? You bet it is, and more recent U.S. definitions about rye notwithstanding, that's the way it has been for some 200 years now.