Newcomers to wine often describe their first impressions of its taste as “vinegary” and “sour”. My younger brother and I agreed, having tentatively sipped champagne in our early teens, that its taste was similar to that left in our mouths after we’d vomited. Our virgin palates correctly identified wine as an acidic substance. Almost all wines have a pH somewhere between 3 and 4 – well to the north of water’s neutrality (a pH of 7 or so).

Beginners often prefer sweet wines for the simple reason that sugar balances (or masks) wine’s intrinsic sourness – thereby duplicating the refreshment and seduction of fresh grape juice. In dry wines, that sugar has been transformed into alcohol (and carbon dioxide), but the acidity remains disconcertingly palpable. After a while, of course, the palate acclimatises. Or does it? The more closely one examines the presence and role of acidity in wine, the more vexed and myth-laden an aesthetic issue it comes to seem. It is also an area in which the acid-loving “professional palate” can seem out of synch with the acid-shy “ordinary palate”. There are, too, striking differences in how national palates respond to acid levels in wine.

Assuming all the acidity in wine is natural (a dangerous assumption, as I’ll explain), then a guide to working out how acid or otherwise a wine might be is to gauge whether it comes from a cool wine-growing climate. Within France, for example, a white wine from Muscadet (grown close to the mouth of the river Loire) will always be higher in acidity, and more palpably structured by acidity, than a white Châteauneuf-du-Pape (grown in one of the country’s warmest wine-growing zones, close to Avignon). Its beauty is of a different order. Great Muscadet is zingy and mouthwatering; great white Châteauneuf is ample, unctuous and thick-textured. A cool climate, it’s worth noting, can be defined by both latitude, as in the example above, and altitude: wines grown in the mountains of Sicily or Corsica are fresher and more acidic than those grown in the warm coastal plains of each island.

Naturally high-acid wines

Muscadet, Saumur, Chablis, Jura vin jaune, Barbera d’Alba, Mosel trocken wines, Champagne, English sparkling wine, Santorini Assyrtiko, vintage Madeira Naturally low-acid wines

Châteauneuf-du-Pape, Condrieu, Bandol, St Chinian, Languedoc La Clape, Alsace Gewürztraminer and Pinot Gris, vintage Port

This relationship between climate and acidity, though, can be both tweaked and subverted. One tweak would be to change the grape varieties in your vineyard: some are later ripening, and better at acid-retention, than others. Those making wine in warm or hot climates, too, sometimes choose to harvest earlier than they might do when growing the same grape varieties in a cooler climate. The benefit of early harvesting is more natural acidity, which drops swiftly as full ripeness approaches; the drawback is that the other components of the grape may not then be ripe. Such wines often lack wealth and articulacy of aroma and flavour as a consequence, and taste mean and raw.

And the subversion? Everything I have written above is based on the assumption that the winemaker wants, above all, to make a wine that truthfully reflects the flavour and balance of the harvested grapes – and, by implication, the climate, landscape and soil conditions in which they came into being. (This sense of “placeness” serves as a rough translation of the French word terroir.) But winemakers might not want to do that; they might just want to make “a nice drink”, or a wine of robust microbiological stability (high-acid wines are more stable than low-acid wines). So acid can be added to wine, even if the resulting balances are, in terroir terms, chimerical. Like all wine additions save sulphur, this need not be acknowledged on labels – a clear and bewildering contrast to food labelling regulations in Europe and elsewhere, which do require additives to be listed on labels. Wine producers have been allowed to get away with non-disclosure of additives for too long.

As a Briton who has lived over the past five years in both Australia and France, it became apparent to me that the Australian palate relishes acidity in wine and prepared foods to a much greater extent than the French palate – which in part explains why so many Australian wines, especially red wines from warm regions, are routinely acidified. The German palate, too, is devoted to acid flavours (hence the importance of the sometimes austerely dry “trocken” versions of Riesling classics preferred in Germany). North and South American palates favour softer acid balances, as does the Spanish palate. The Italian palate is unclassifiably diverse – or one of magnificent breadth.

2012 Châteauneuf-du-Pape Blanc, Domaine de Beaurenard (£27.49 at allaboutwine.co.uk). This six-variety dry white blend is both remarkably low in acidity yet has a low pH, too. It smells of dried wild flowers and straw, and tastes rich and chewy, with hints of cream, almonds, marrow and nougat: shy yet haunting.

One of the most pernicious myths in the wine world is that a wine “needs” prominent acidity in order to age well, whereas what age-worthy wines in fact need is a combination of density of flavour, aromatic precision and overall harmony, generally attained after generous vintages in the lower end of the acidity spectrum for the region and variety in question. This myth perhaps springs from a confusion, even in seasoned mouths, between acidity and concentration (the more acid a wine is, the more concentrated it will seem to be); or is based on the fact that acid in any case becomes increasingly prominent in the flavour spectrum of most wines as they age, and the youthful impression of fleshiness and richness drops away. The greatest wines keep their acidity at bay – or in balance – for longest.

These are, though, difficult issues to calibrate perfectly, not least because pH and measured levels of acidity in a wine do not always correspond. “In a great wine,” I was told at Ch Cheval Blanc recently by soil consultant Kees van Leeuwen, “you can have a lot of freshness without necessarily having acidity.” Bordeaux’s transition, over the past three decades, from being a region producing alcoholically light, acid-prominent and sometimes roughly tannic red wines in most vintages to one producing alcoholically moderate to ample red wines whose structure no longer comes from acidity but instead from generous but sumptuously textured tannins with a non-acid freshness of their own is remarkable. My palate (perhaps over-sensitive to acidity) greatly welcomes it. Others disagree.

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Jancis Robinson is away.

Andrew Jefford’s blog ‘Jefford on Monday’ appears each week on decanter.com

Illustration by Ingram Pinn