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Most people hoping to celebrate with glass or two of champagne this festive season will probably try to avoid agitating their bottle of bubbly before serving.

Shaking bottles of champagne has become widely associated with flying corks and the kind of messy spraying of liquid normally restricted to the winners podium in Formula One.

But new research now suggests that actually giving your bottle of champagne a good shake before serving may help to reduce the risk of unwanted explosions upon opening.

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Cheers! French researchers have shown that shaking a bottle of champagne actually decreases the pressure inside and in turn reduces the risk of unwanted explosions when opening a bottle of bubbly

French scientists have found that vigorously shaking a bottle of champagne can actually decrease the pressure that builds up inside the bottle.

The key, it seems, is waiting for the right amount of time before opening the bottle.

They found that although the pressure initially drops when champagne is shaken, huge numbers of 'super critical' bubbles form in the neck of the bottle.

This is what leads to the characteristic effervescence that occurs when a bottle is opened.

However, after around 40 seconds the number of bubbles in this state begins to decrease until they have completely disappeared 220 seconds - just over three and half minutes - after shaking.

At the same time, the pressure inside the bottle starts to increase again but plateaus around 0.1 bar less than the original value.

Professor Gérard Liger-Belair, who led the research at the University of Reims in Champagne-Ardenne, said: 'A popular belief is that the pressure increases when a bottle is shaken and that is the reason for gushing of the liquid when the bottle is opened.

'We show that shaking in fact produces a small but opposite effect, in the form of a transient pressure decrease.'

However, their research also cautions against shaking bottles of fizzy drink that have been resealed after opening as this can result in an increase in pressure.

The explanation for this counter-intuitive behaviour of champagne has to do with the dynamics of the bubbles inside the liquid.

While sealed, the carbon dioxide and alcoholic liquid form an equilibrium where the gas is continiously dissolving and effervescing at the same rate.

Shaking however instantaneously creates lots of large bubbles as the free gas and liquid mix. However, as these bubbles start to collapse, some of the gas they contain in is temporarily dissolved in the liquid, reducing the amount of free gas in the bottle.

As gas requires more space than liquid, this reduces the pressure on the cork.

The findings build on previous work by Professor Liger-Belair that showed cooling bottles of champagne can reduce the speed of the cork as it leaves the bottle.

The scientists tested champagne and sparkling wine in adapted bottles (illustrated, right) and water in an aluminum container (illustrated, left) which were shaken for 20 seconds, allowing pressure to be measured

Pop that top! SHAKE champagne before opening?!

He recommended cooling the bottle to 39 degrees F (4C), which causes the cork to travel at three quarters of the speed when it has been left at room temperature.

Their latest study now suggests that also giving the bottle a shake a minute or two before serving can also help to keep prevent any mess accidents.

It is thought that as many as 900,000 people injure themselves or cause damage with flying champagne corks or by spilling the liquid each year.

Around eight per cent of these are due to a cork hitting someone in the face, according to a survey by Morrisons in 2011.

Damage to lights, ornaments, furniture, fittings and clothing account for around 15 per cent of the champagne related incidents.

Shaking causes a pressure to drop inside the champagne bottle and then to slowly rise before plateauing at a level less than it was originally

Doctors have also warned that flying corks can cause serious eye injuries and even blindness in the most extreme cases.

Professor Liger-Belair has also found that the average glass of champagne produces around one million bubbles - provided it is not drunk.

In the latest study, which he conducted along with with scientists at the Centre de Recherche Paul Pascal in Pessac, France, the researchers tested the effect of shaking champagne, the sparkling white wine Blanc Foussy and carbonated water after shaking them for 20 seconds.

They found that the pressure in each of these liquids dropped after shaking before slowing increasing again over time.

In the carbonated water there appeared to be an overall decrease in pressure after shaking of around 0.1 bar.

Tests in the alcoholic wines, which have different viscocities to water, only showed slight differences compared to the water, according to the study, which is published online in the Journal of Colloid and Interface Science.

They also filmed the formation of bubbles inside bottles of champagne after they had been shaken and found that huge numbers of bubbles initially form when shaken but after 220 seconds they have completely disappeared.

Professor Liger-Belair said: 'If opening occurs just after shaking, the immense majority of bubbles are super-critical, and then effervescence starts fiercely.

'There is no pressure increase prior to opening, and the pressure in the bottle neck keeps close to zero once the bottle is opened.

'Gushing only lasts for a few seconds, but can be prolonged by continuous shaking of the bottle. Gushing lasts as long as the generated bubbles are larger than the critical size.'

Scientists say that before shaking the carbon dioxide gas and champagne liquid is in equillibirium (left) but shaking causes bubbles to form as the two mix toghether (b) and then as the bubbles collapse some of the CO2 in the bubbles dissolves in the liquid, meaning there is less free gas in the bottle to create pressure (c)