I WENT to Islay for the peat and the sea. Seemingly alone among whisky lovers, I was fairly new to single-malt (unblended) Scotch whiskies, having attended a few tastings in this country that left me bewildered by their variety. Nonetheless, I was firm in my preferences: however many whiskies were on a table, I always gravitated toward the smoky, tarry fragrance of peat -- the compressed and partly fossilized loam of sphagnum moss and heather -- used to roast barley. What I most like is what makes Scotch single-malt most different from other whiskies. Irish almost never uses peat and usually includes unmalted as well as malted barley; rye and bourbon are based respectively on rye and corn and are also unpeated. Peat is what kept the most distinctive Scotch whiskies from acquiring a wide and appreciative audience until relatively late in this century.
My goal was to connect the land, the sea, and the air to the taste in the bottle. To do this I wanted to walk through a bog and steep myself in the smoke of a peat fire. Islay, jutting into the Atlantic in the Inner Hebrides, west of the Scottish mainland, had it all, I was told: miles of peat bogs, malted barley hand-raked and roasted on site, and six working distilleries, most of them right on the sea -- resulting in the lip-smackingly salty aftertaste I had also come to crave.
Wood is said to account for as much as 50 to 70 percent of a whisky's flavor. Whether or not flavor components can be assigned precise percentages, the estimate is plausible, given that the flavors in most distilled spirits -- vanilla; the burnt sugar of caramel and toffee; coffee and chocolate; various spices, including cinnamon and ginger; and fruit, especially citrus -- are imparted chiefly by oak, and Scotch whisky must age at least three years in wood. In Scotland today that almost always means bourbon barrels made of American white oak, whose interiors have been charred to give color and strong vanilla and fruit flavors. By U.S. law bourbon barrels may be used only once, so when they arrive in Scotland, the oak has plenty of flavor and honey color left to give to the transparent "new-make" spirit as it ages. In the Scotland of the past century the wood was often European oak in the form of Spanish sherry barrels, which were shipped full and sold off to distillers after their contents had been bottled. Today Spanish law requires sherry makers to ship their product in bulk, and sherry barrels have become a rare and expensive prestige item for distillers who want the sweet, citrusy flavor and deep-mahogany color they give.
The flavor that makes me snap to attention seems like distilled smoke that yields to classic vanilla, orange, and toffee and returns to smoke for an aftertaste that can last for hours. I seek the initial slap of what some people call "motor oil" or "iodine" -- its technical name is phenol, and it is the chief chemical flavor component of peat smoke -- and then savor the more delicate flavors that appear. The shock of the first whiff followed by subtle, lingering pleasure in the mouth is like diving into a cold pond and then deciding you don't want to get out. I've never joined the quest for ever-hotter chili peppers, but hunting for peat has made me understand the addiction: once you acquire the taste, whisky seems incomplete without it. On Islay I found fire in high-proof "cask-strength" whiskies, and smoke everywhere.
MY bog craving, I learned when I arrived, was misplaced. Like mesquite wood chips, peat briquettes have no aroma until they burn. That's why the little dried clods of earth I had grabbed for and rubbed against my fingers at tastings in the United States were disappointingly odorless. The fault wasn't the age of the peat or the overseas shipping. It was the lack of a flame.
What is being smoked is a grain, and in my initial research I assumed that the variety of barley must be very important. Indeed, The Macallan, a distillery on the mainland, is proud to use only Golden Promise, a low-yielding old-fashioned barley that it pays farmers to grow -- and to grow only from a seed it has patented. (It may be reviving a nineteenth-century custom, but we are entering the genetically protectionist new millennium.) A heavy peating, as roasting barley over peat is called, will dominate the flavor of any variety -- and Islay distillers are the heaviest peaters of all.
In malting, barley is soaked in water and spread out on "malting floors" to germinate for several days, so that enzymatic action will convert starch to sugar as the seed prepares to sprout. Distillers want to stop the growth before a shoot emerges, so that the shoot won't get a chance to use any of the sugar they plan to convert to alcohol. Heat kills the germ and hardens the rubbery wet barley, allowing it to be crushed; the grist is mixed with water and cooked like a porridge at a gentle heat that is just right for yeast to ferment the sugar to alcohol. (The type of yeast the distiller chooses to add determines the presence and level of flowery flavor overtones.) At this point the distiller has made beer; malt whisky is distilled beer, as cognac is distilled wine.