The Other Aromas of Winemaking – Wine-Searcher

Every year it happens and it always makes me smile.

I know it’s coming but it still somehow feels serendipitous, a seasonal joy, something of the miracle of existence: the first smell of fermenting grapes.

This year – and to be honest, like most years – it was Chardonnnay. But, to be honest, the variety doesn’t matter so much; the bouquet is pretty similar across them all – sweet, heady, immediately recognizable. I smell it and it makes me happy. But not all fermentation is delightful. It normally starts that way (although not always) but, as the sugars drop, things can go, well, unusual.

I haven’t worked a lot with Riesling but when I have, it seems to smell deeply unpleasant through ferment (had I not been warned at the time, I would have proposed remedial action). With ferment through, the aroma seems to undergo a metamorphosis of sorts and, while the beautiful butterfly shows hints of the once vulgar caterpillar it was, it is a new beast. Since starting out making wine, I never felt the winemaker had much of a claim over how their wine should be perceived (in the same way as the author or the artist cannot dictate the “meaning” of a work) but we, the people who shepherded it along, were privileged, in a sense, to behold the evolution. I don’t want to fan the flames of Riesling adoration (equal parts true, righteous, boring and futile) but it felt a bit like that watching it undergo the change. But there are elements of that across all wines.

Struggling or reductive ferments are particularly unpleasant to behold. Their contribution to the aromas of a cellar mid-harvest seems to far outweigh their size. It doesn’t take much of the burning rubbery, oniony affront to pollute the air. Like opening a jar of fresh kimchi, you don’t even need to be paying much attention for your nostrils to register. And, in a cellar situation, the emergency light comes on: stinky ferment. I’ve once confused the smell of a particularly smelly Syrah ferment for the smell of a burning rubber pump impeller. That’s quite something. If you want a comparison, the smell of a burned-out pump is a bit like that of burning plastic. It’s what happens when a pump has nothing to pump but keeps pumping nonetheless, it gets progressively hotter and the rubber impeller begins to melt. Sometimes it’s bad enough to see the smoke curling out of the end of the pipe at the end of the line. It’s more than enough to ruin a tank of juice or wine – that’s why winemakers smell everything all the time.

Anecdotally, that’s often how they die. Crouched at the top of a fermenter, checking a ferment before going home or on arrival to the winery (the two times when few people are around), they lift the lid to smell how things are going, the hit of carbon dioxide is so violent, they recoil, they trip or hit the back of their head, and the rest is particularly awful. I don’t know that carbon dioxide has an aroma as such – up close and outside of the regular ferment smells, it certainly seems to have a distinctive, acrid note – but you quickly get a feeling for it. It can lend an urgency to one’s desire to exit (cellar, room, fermenter) that is terrifyingly primordial. That fear and hurry is also, clearly, the route of accidents. Don’t ask me how I know, but in high enough concentrations it makes your eyes burn and water. This whole paragraph is a classic of cellartalk: equal parts pontification, brag, and a call for health and safety oversight, and a reminder that most conversation is founded on bad news.

Damp and drains

Outside of vintage, the smells of the cellar are generally unremarkable. Which is as it should be. Anything else might be cause for concern. Dampness – the odor of water on concrete or water in the drains – is sporadic, although I have worked in a cellar where there was a peculiarly damp/moldy smell that you’d get in certain areas and, no matter where you looked and cleaned, it would return occasionally. I’’m not sure if it was a combination of hot water washing and residual wine or lees. I suspect it was the drains.

© NSW DPI | Grape marc decomposes and quickly takes on a vinegary smell.

Drains. Extended periods spent in wineries lend an appreciation for the hitherto mundane aspects of winemaking. Cooling systems is one, the efficiency of drainage is another. A combination of lees, static water, and the warmth of spring/summer is a combination I can only describe as utterly gopping. (I owe my unwanted knowledge of the hardy, rat-tailed maggot to my dealings with winery drainage systems.) In fact, lees is a regular source of aromatic horror. The French distinguish gross lees (the solids from juice, or “bourbes”) from wine lees (the post-ferment solids at the bottom of a tank or barrel, or “lies”, as in “sur lie”). Gross lees quickly become gross. A lot of wineries will combine them in a tank either to filter or to send out for distillation and the chances that they start fermenting are high, no matter how cold your tank, or how much sulfur you chuck in – literally. I’ve sat at the top of a fermenting lees tank (the most vile, fetid odor – effectively an uber-reductive ferment, smelling of the worst organic drain – you can imagine), emptying bags of sulfur into the top in an effort to slow the beast.

Other bad smells include those of decomposing marc. By-and-large, most wineries will ensure this gets cleaned out – grapes (pressed or otherwise) and stems quickly turn acetic and smell like vinegar. Not only does it smell pretty high pretty quickly, it’s also a vector for fruit flies – the bane of winemakers year-round, but especially in autumn. While it should be a rare smell in a winery, it is hard to avoid discovering it somewhere during harvest.

Another cellar trigger for me, aromatically, is the exhaust of an LPG forklift. In fact, I reckon that, on a perennial basis, this is one the most evocative smells around a winery. Forklifts are used all the time, even in a lot of small outfits: moving barrels, tipping fruit, transporting dry goods, carrying people to make repairs, and so on. That smell of an LPG forklift exhaust is a particular mercaptan, immediately recognizable and ubiquitous (something like rotten eggs or cabbage or fart but it’s somewhat unique to LPG – I almost like it).

I like it in the same way I “like” the smell of welded or ground stainless steel. That was possibly my first major winery aroma: I’d turned up for harvest at a new winery in Spain and welders were still fixing the cooling jackets on the stainless steel tanks. It smells like, well, like burning metal. It’s burnt and not quite sweet, it’s metallic – obviously – but if you’ve been around a sawed a bit of metal before, you’ll get the idea. It’s industrial. Before long, you’re around people doing all sorts of things to stainless steel fittings: grinding, welding and so on.

Wooden it be good?

From the ridiculous to sublime, one of the best harvest odors in a winery is that of new oak. Every year, it is irresistible. There is surely a primordial trigger to our love of the smell of smoke, but that combination of warm, almost sweet, oak and toast is sublime. Like grandad’s woodwork bench and a handful of roasted coffee beans. We all lose ourselves a little bit in the smell of new oak. Combine that with the sweet, creamy, citrus smell of fermenting Chardonnay – in fact, a clean ferment of almost anything – and you’d be forgiven for wondering why anyone would pass up on the resulting wine. Screw it all, you’d drink the cellar dry.

Indeed, oak or no, most ferments smell fantastic. They generally go a bit awkward in the last stage but they’re still pretty lovely (the aromas of gauche, freshly fermented wine are generally tempered by its shocking dryness on the palate). Then it comes to pressing and the smells of marc. If pressed white grapes smell green (a sort of fruity, herbal, fresh “green” smell), then pressed red ferments are heady, autumnal. They have a certain high, fruity-resin combination; it’s neither unpleasant nor particularly attractive. Some people save marc and cook sausages in it and, as a dish, it’s much like the basic medium: individual, unique, but not exactly we-should-do-this-all-the-time. It’s very evocative, though. Grappa gives you a bit of an idea.

Last year, I wrote a piece about the sounds of the winery. As I walked into the winery this year and smelled that first ferment I knew the follow-up would be easy enough. What’’ hard is finding descriptors. But that’s half of tasting anyway.