For people in Spain, it is a bit like the Coca-Cola wars, as consumers try to decide the question: Which is really better, Coke or Pepsi? And how far can each company legally go to outdo the other?

In the case of Cava, or Spanish sparkling wine, the two main contenders are Freixenet and Codorniu.

Both are produced in the north-eastern Catalonia region, according to the stringent quality controls which have allowed Cava to compete internationally with French Champagne.

Some years ago, under pressure from the French Champagne lobby, the European Commission ruled that Cava producers were not allowed to label their bottles "M�thode champenoise" even though their sparkling wine is made in exactly the same way.

But this may have been a favour in disguise. Since then, Spanish Cava has been able to establish its own sound footing in the global market.

Fierce competition

Bitter rivalry between the two main Cava groups has taken some of the joy out of the celebrations.

While production of the aristocratic Codorniu goes back to the year 1551, Freixenet is a relative upstart, beginning production in 1915 in the same town as Codorniu.