I'm hunched over a sink in the tasting room of an exquisite cognac house in southwest France, staring in horror at something I've just spat out. See that brown stain sliding down the plughole? That’s a mouthful of Frapin 1888, an elegant spirit I’ve been rolling around my tongue, before bending to... well... spit it out.

Now I discover that this particular bottle can cost a knuckle-whitening £4,500, which means, let me see, that stain’s worth £45. Yet as I turn back to the tasting room the cellar master is already pouring another slug. “Cheers!” I cry, perhaps a little too gaily.

It’s ten in the morning, you see, and I’ve already tried three samples, some of which I’ve not actually spat.

And welcome to my course at the Cognac School, in the sweet medieval town that gives the drink its lovely name. Over two days I shall sample at least 22 varieties of spirit. But this isn’t binge-drinking because it’s education, see?

Fetching up for class this morning I’d felt embarrassed, diffident, like some schoolboy up for a whacking, because that’s how high-toned appreciation of the savoury arts affects me. But I was charmed by my teacher, Véronique Lemoine. Teacher? Life partner! Joyful companion! It’s the cognac talking, but Véronique was elegant and dazzlingly knowledgeable and spoke with an ooh-la-la accent.

“My idea is to explain cognac,” she said, “not only how you make it but show what it is by savouring and tasting.”

In fact, Cognac School is aimed at amateurs and visitors as much as trade professionals, so over the next 48 hours Véronique took me on a brilliant barrel-sniffing, liquor-licking tour through vineyards and tasting houses, museums and distilleries that stipple this mellowed corner of France. A landscape adorned with names such as Rémy Martin, Hennessy and Camus became my classroom.

Scraping together now the stuff I remember, I can tell you that the complexity of cognac’s taste starts with the choice of region from which the originating wine is drawn – six in all – and goes on to encompass, bewilderingly, the kind of grape used, speed of distilling, ageing process, type of barrel oak, blending . . . blah blah. I forget.

But if you want to know the heart of it, picture this scene. Here we are again in an environment that has become, by now, pleasingly familiar. This is the tasting room of a tiny company called A.E. Dor, which blends superior cognac selected from thousands of basic spirits, or “ eaux de vie”, available from surrounding producers. This building is cranky, mellowed, old and pitted, its floors uneven, walls lichen-covered below arching wood-beamed roofs.

The atmosphere stuns me. This room smells of barrels and spilt liquor, decades of open bottles and clinked glasses. It is similar to others I have visited, yet the silent, ancient chill here distils, for me, the core of the process, and my lessons.

On a table sit all 11 varieties produced by this company, while standing near by, clutching a glass and smiling with transparent bonhomie, is the owner, a character called Jacques Rivière, who clearly loves Véronique as much as I do, but I forgive him because his cognacs are so fine. One after the other.

Sometimes I spit, but that seems too crude an ending to a process that is almost religious in nature – the tasting, the sensory response – so sometimes I don’t.

Véronique has explained that there are at least 60 “notes”, or smells, discernible to the educated cognac palate, but in a test she set me, back in the fog of memory, I mistook sandalwood for orange blossom, so my nose is clearly F-level GCSE. Yet here I am hobnobbing with masters. What to say? What to risk? I sip. They look. I say, “Leathery? Powerful? Slightly, um, earthy?” I continue, “An explosion of force with a bitterness at the end?” I blush. “Mmm, spicy!”

Jacques is too polite to giggle and so is Véronique, but I feel they should – this rampant amateurism, this pretence. But there again, it dawns on me that this is the point: I’m learning. During our two days together, cruising the beautiful Cognac Museum in particular, Véronique and I have debated over and over the issue of whether knowledge – understanding – is necessary for enjoyment.

We kicked this ball around and around, never settling the issue between us. Yet standing in the tasting house talking to Jacques, knocking back glass after glass, I realise for the first time that in struggling for terms to fill this terrific pause in life’s usual business, I am thinking about what’s on my tongue. It’s just that my tongue can’t express what’s on it.

Need to know

The Ecole des Cognacs (www.ecole-des-cognacs.com) tailormakes tasting and appreciation courses. Two-hour tasting courses for up to eight people cost from £27pp; full-day courses are from £48pp, but visits and tastings can be adapted to fit any length of stay. Distillery visits are also available – see www.visitcharente.com, www.poitou-charentes-vacances.com and www.franceguide.com.

The Château de l’Yeuse hotel in Cognac (00 33 5 45 36 82 60, www.yeuse.fr) has double rooms from about £83, excluding breakfast. Ryanair (www.ryanair.com) flies from Stansted to La Rochelle, where hire cars are available; it’s a 90-minute drive to Cognac.

3.4 per cent: The volume of cognac that evaporates every year in the ageing process
27 million: The number of bottles of cognac that are lost every year to this ‘angel’s share’
Source: www.cognac-world.com

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