The first proper plant I’ve thought about discussing here is Sphagnum. Sphagnum is a genus of moss that is a principal component of peat. And peat bogs are interesting places. For one thing, they possess a remarkable preservative ability — take, for example, the 8,000 year old Koelbjerg Woman discovered in a Danish peat bog.
But more impressive to me is this: peat harvested from the Scottish island of Islay is burned to roast the barley used to produce a particular (and, to my palate, particularly good) malt of Scotch whisky.
This fall evening, thinking on the smoky, briny flavor of Islay Scotch, I’ve been wondering how it is that burned peat produces this distinctive flavor. A Globe and Mail article outlines some basics:
Peat freaks measure their pleasure in parts per million of phenols, the chemical compounds responsible for the smoke. …
Peat contributes not only smoke but nuances of iodine (especially in the case of Islay peat), seaweed, salt and damp earth.
I’m not a scientist, so I wonder what might be a more detailed explanation for the nuanced flavor that results from the burning of peat. My hypothesis is that flavor comes from the outer layer of Sphagnum moss, which contains two types of water-retaining cells, retort cells and hyaline cells, that give it the ability to hold “25 times its dry weight in water.”
If Sphagnum retains so much seaweedy, salty, earthy bog water, then some chemical components of this seaweedy, salty, earthy bog water must stay behind when the Sphagnum is dried for burning.
Is this right? If it isn’t, what’s the proper explanation? And if it is right, can anyone provide more detail? All I know is that if my hypothesis is right, it’s a fine combination of impressive morphology — Sphagnum‘s ability to retain water — and environmental factors that lend Islay Scotch its glorious signature flavor.