I was in the south of France, having a little look around whilst the 2009 harvest was in full swing. It is a fabulous time; the vineyards are speckled with pickers, the wineries are a hive of activity and the air is full of the smell of fermenting grape juice. Marvellous!

It is also a rare opportunity to taste from tank; which is to taste the new vintage in its very earliest stages. As it happens, I manage to gatecrash a winery just as the consultant oenologist arrives to do his daily checks.

We opted to look at the Chardonnay wines. Each of the individual Chardonnay plots were harvested separately and, as a consequence, were all in varying stages of fermentation in separate tanks.

The first noticable difference from these versus finished wines is that they come out of the tank much cloudier; like freshly squeezed apple juice. The aromas are not pure fruit either. There’s the challenge of getting beyond the whiffs of sulphur that are a by-product of fermentation and a host of other unexpected smells that are really distracting.

What, I ask the oenologist, is he looking for? “To make sure it doesn’t smell strange or bad.”

As I’m fast-learning, this is not as easy as it sounds. It is completely different from tasting finished wine because all the properties that you have been taught to look for are not there.

Or, if they are, they are presenting in very different ways.

I imagine it is like people who can dip into raw cake mix and know what it will taste like when it is baked, and who know instinctively whether there is something missing.

Depending on where in their fermenting journeys these wines were, the level of sugar was still very high or barely perceptible. More than once I was caught out because the fruit character of some sites was richer and, as a consequence, tasted ‘sweeter’.

I was also thrown by two tanks that contained grapes from identical sites but where different yeasts had been added to influence taste and final alcohol levels.

We are about seven samples in when I taste something that I describe as ‘raw’. “Yes,” my tutor advises “that’s right; you’ve picked out the wine that has reached the end of fermentation . . . it’s now dry.”

The next step is identifying the qualities of this infant wine and determining what course of action will help it reach its full potential. The oenologist will decide — amongst other things — whether ageing on the lees will benefit or perhaps some time in barrel.

In the end, we only tasted a dozen or so tanks but I was utterly exhausted come the finish.

My senses had taken an almighty beating. It was a truly fascinating experience that threw up many more questions than answers. The greatest of all being: How on earth do they ever know how to blend these tanks to create the wines that they do?

It takes a phenomenal expertise to understand your product so well at this stage that you can predict the qualities that the wine from each tank will bring to the final, blended wine.

I left the winery tired but deeply inspired. I have long maintained that wine is made in the vineyard and not in the winery, but when you have an experience like that it is only the crazy that would not give the winemakers the credit they deserve.

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