Heavily peated

Where flavour comes alive

Last month, we sailed from the mainland to the Hebrides and Orkney to dig a little deeper into the subject of peat. On the voyage home, vicious autumn weather battered our ship, and we did not make it to port. So, we aimed for the nearest spit of land hoping for the best.

Now stranded, Julien Willems rides out the storm while sharing the last chapter of our story on the Society’s trio of peated flavour profiles. It’s time to get Heavily Peated.

The burning question

Now let’s start the story of the Society’s Heavily Peated flavour profile. As seen in our previous exploration of peated whiskies, the origin of peat matters and can impact the aromas we perceive in our drams. Indeed, peat is important, and the more intensely the malt is smoked, the likelier it is the resulting whisky will be peatier and smokier. But in a world plagued with increasingly extreme weather phenomena, this begs a couple of questions: how much peat is used by the Scotch whisky industry? And how sustainable is that use?

For some time now, whisky producers have been acutely aware of the issue of burning peat. Peat is technically a fossil fuel, storing carbon contained in plants grown millennia ago. And although it is an abundant material, the variety of some of the peat extracted for whisky in Scotland comes from lowland raised bogs, which are a specific type of ecosystem that has come under severe pressure in the modern era. According to the Wildlife Trusts conservation charity, 94 per cent of UK lowland raised bogs have disappeared due to human activity, draining them to plant trees, crops or build houses in the last hundred years. Such an extreme situation means an unfathomable pressure on biodiversity and is equally terrible news for the environment in general. Not only are these peat bogs carbon sinks, they also act like giant sponges, storing water and filtering it slowly, protecting against both drought and floods.

To cut a long story short, the Scotch Whisky Association, the trade organisation representing the Scotch whisky industry as a whole, in partnership with environment protection NGOs, have set out to make the industry carbon neutral by 2040. To do so requires some serious changes and clever solutions to complex and far-reaching issues such as energy production, malting, distilling, packaging and supply chain and distribution. There are good reasons to be hopeful though, as many newcomers are leaning strongly on a sustainable and durable strategy (see Nc’nean, Ardnamurchan or GlenWyvis among others).

This 2040 milestone will very much affect the usage of peat in the Scotch whisky industry. Lowland raised bogs are fragile and although the Scotch whisky industry only uses four per cent of the peat cut from these ecosystems (the vast majority being cut by the horticultural industry), extracting even a seemingly small quantity of peat from these ancient grounds can cause them irreparable damage. Think of it as a rich, peated whisky-saturated chocolate fondant. If you take a spoon to it, no matter how small the bit you take away, you’re guaranteed to have chocolate leak out all over your plate. While that might sound delightful where puddings are concerned, the same cannot be said for the peat bogs. Bleeding out fluid means a lower water table and fast decaying peat due to oxygen exposure in drier conditions. This means that large surfaces of traditionally waterlogged carbon storage all of a sudden turn into an equally sizable source of carbon dioxide emissions.

Not for the feint hearted

On the distillation front, distilling peated malt is a bit like walking on the edge of a cliff. The more phenolic compounds a distiller desires in their whisky, the longer they will have to push their distillation. Indeed, “phenolic compounds do not want to be distilled” as Dr Barry Harrison of the Scotch Whisky Research Institute humorously puts it. Naturally, these molecules do not have a will of their own. What they do have is a much higher boiling point than ethanol, fruity esters or even water. This means that they come in larger quantity through the still later in the distillation, encroaching on the territory of feints (sweat, cheese and old socks aromas).

This can evidently cause issues, but as luck would have it, phenolic compounds have a potent masking effect on other flavours as we are essentially wired to detect them in even the smallest of quantities. It doesn’t mean you can go overboard, though. Feints are generally bad news and their flavours will not go unnoticed. But while keeping your distillation clean, distillers have other tools to help those heavier, oily and medicinal tasting compounds through the stills. As Dr Harrison explains: “It’s a good idea to remove barriers that would prevent their passage through the still.”

One such obstacle is the lyne arm, the piping running from the swan neck at the top of the pot still’s neck. If it is angled upwards, the rule of thumb is that oilier and heavier compounds will generally condense and trickle back into the pot, creating a high abv and lighter spirit.

If the lyne arm is angled downwards, no matter if the heavy stuff cools down before hitting the condensers, it will nonetheless end up in an oilier, heavier spirit. So, the still’s anatomy does play an important part here, but it’s not the only factor.

On the research side, ultimately, as SMWS spirits educator Dr Andy Forrester explains: “There are indications that even when phenolic compounds are extracted from a whisky, certain aromatic elements associated with peat seem to remain.” As surprising as that may sound, this suggests that as we have often seen before, things are not as simple as looking at how many ppm (parts per million) of phenolic compounds are in peated barley. Phenolic compounds evidently play a big part in creating the flavours we perceive in our Heavily Peated flavour profile. However, we are not entirely certain of what other mysteries lurk behind the smoke and result in aromas we perceive as peated or burnt. The story could continue, but it seems the storm has passed. In the distance, we catch a glimpse of moonlit clouds swallowing ethereal, frost-encrusted mountain tops. Nevertheless, come storm or darkness, our hard-working maltsters, distillers and researchers burn the midnight oil. I hope you will join me in supporting them in spirit by pouring yourself a Heavily Peated dram.

Here you can read more from Wildlife Trusts on raised bogs.