WHAT ARE BUBBLES?
They are just carbon dioxide, and they have lots of ways of finding their way into wine. Some are better than others. The fun of the effervescence also affects the taste.
The easiest way to bubble wine is just to exhale into it through a straw. Simple. All children (and some adults) do this at parties. Their drinks erupt with short-lived carbon dioxide bubbles.
It is exactly the same principle with commercial fizzy drinks. Cola becomes bubbly when carbon dioxide from a tank is pushed through it. In fairness, you can do this with wine too. Heston Blumenthal bubbled Blue Nun through a Sodastream and that did the trick. You can probably buy inexpensive carbonated wines in your local supermarket right now.
THE ANTI-BUBBLE BRIGADE
Although we love bubbles in wine today, historically they were seen as a fault. When they happened accidentally the ancient Greeks and Romans believed they were caused by evil spirits or the phases of the moon. Bubbles were bad.
Depending on the translation, some version of the Bible even warns against bubbly wine:
‘Look not thou upon the wine when it is red, when it sparkleth in the cup, when it goeth down smoothly’.
Which – let’s face it – pretty well covers any wine worth drinking.
Wine is just grape juice that has been fermented by yeast. Yeast eats the sugar in the grape juice and gives off alcohol and – you guessed it – carbon dioxide. (Spoiler alert! Potential bubbles.) The carbon dioxide escapes from the tank or the barrel into the atmosphere – just like a human breathing out.
Sometimes, after the grapes are harvested in late Autumn and the grape juice is fermenting away merrily, suddenly, everything stops. If you get a cold snap or an early winter, the yeast gets too chilly to function. It just falls asleep and hibernates.
Its quite happy being totally dormant and floating about in the wine. When it warms up again – usually in Springtime – the yeast warms up, wakes up and starts fermenting again (provided that there’s enough sugar left for it to eat). This is ‘secondary fermentation’. So far so good.
But what happens if, while your sleeping beauty yeast has been snoozing, you have put it in a bottle?
It wakes up. It starts fermenting again (if it has enough sugar). It makes carbon dioxide bubbles, but they can’t escape from the bottle. So what can they do? They dissolve into the wine. All 49 million of them.
IT ALL STARTS WITH AN APPLE …
Like so many delicious temptations, it all started with an apple.
In the seventeenth century, England was full of apples. Naturally English cider was a big hit in the 1600s. It turns out, Fizzy cider was top of the pops (sorry).
Although fizzy cider could happen by accident, this rather depended on there was enough sugar left in the apple juice for the yeast to eat when it woke up. It was a bit hit and miss. This ‘cross your fingers and hope’ method is known as the ‘ancestral method’.
But canny cider makers could guarantee bubbles. How?
Simply by adding sugar at bottling.
English cider-makers knew that if they added sugar to cider at bottling, there was a ready-made yeast feast. This jump-started secondary fermentation. So fizzy cider could be made on demand.
So in 1657 – incongruously when the Chief killjoy Oliver Cromwell was in power – fizz was born. People loved it, and were even prepared to pay a little more for it.
Ralph Austen’s book : ‘The Treatise on Fruit Trees and Spiritual Use of an Orchard’ recommended that ’a lump or two of hard sugar’, or ‘sugar bruised’ should be added to each bottle of cider. By 1662 Rev. John Beal told the Royal Society that ‘a walnut of sugar’ should be added, but by 1663 Captain Silas Taylor recommended a ‘nutmeg of sugar’ rather than a walnut. If kept chilled in cool water he said the cider would
‘drink quick and lively, it comes into the glass not pale or troubled, but bright yellow, with a speedy vanishing nittiness (as the vintners call it) which evaporates with a sparkling and whizzing noise’.
The vintners copied the cider-makers. On 17 December 1662 Dr Christopher Merrett (the Parliamentarian Proctor of Oxford University) told the Royal Society:
‘our wine coopers of recent times use vast quantities of sugar and molasses to all sorts of wine to make them brisk and sparkling.’
Sparkling Wine had arrived.
So by 1662, if not before, the English had bubbles in their wine. They added sugar, which is what we call ‘the Traditional Method’ or (somewhat misleadingly) the ‘Methode Champagnoise‘.
Invented in England.
Bubbles always want to escape. So once you have got bubbles into a bottle, you have to keep them in.
This is not possible with the old-fashioned wooden peg wrapped in cloth and tied onto the bottle with string. Particularly given that the pressure of the bubbles – about 3 times that of a car tyre – which would pop off the bottle stopper. No stopper – no popper. The bubbles would escape. The wine would be flat.
The Romans had used cork stoppers, but everyone had forgotten about it. It was the bubbles that prompted a cork revival. In 1657 Ralph Austen (again) explained that
‘cider might be kept perfect for a good many years by keeping the bottles well stopt with corks, and hard wax melted thereon and boun down with a Packthread’ [sic].
Between 1628 and 1632 Lord Scudamore (later ambassador to France …. Say no more) and Sir Kenelm Digby found that a bottle firmly sealed with a non-leaking cork allowed sparkling wine to be kept for much longer. They set a trend. Corks for wine bottles became so popular that by 1675 even Shakespeare referred to it. Rosalind said to Celia in ‘As you Like It’ :
‘I pray thee, take thy cork out of thy mouth, that I may drink thy tidings.’
By 1685 corks were even being used in France.
Not all bubbly wines are the same. Some are made in the Charmat method. This involves fermenting wine in a pressurised tank until its bubbly and then bottling it under pressure. Its quicker and cheaper and suits fresh, fruity, easy-drinking wines best. It is popular for prosecco.
Some wines say they are ‘bottle fermented‘ which means that they have fermented in a bottle, but not the bottle you buy it in. After fermenting in a bottle, the bubbly wine is decanted into a pressurised tank and then re-bottled. Again this is quicker and cheaper than disgorging it traditionally.
So next time you take a sip, think of those 49 million yeast-induced, carbon dioxide orbs tickling your tongue … and (hopefully) your fancy.