Chardonnay grape vines at Veuve Cliquot

It begins in the vineyards – only three grapes can be used: chardonnay (a white grape with white juice), pinot noir and pinot meunier (black grapes with white juice).  In Champagne grapes for champagne can only be grown in certain regions, which are classified on a scale of ‘Cru’ based on their soil, sunlight, drainage and more.  The best areas are called ‘Grande Cru’ and this name is applied to the village at its heart, the next best are called ‘Premiere Cru’ and the rest, simply ‘Cru’.  Grande Cru champagnes will be more expensive as they occupy a much smaller area of than the rest.  Interestingly, Dom Perignon, one of the most expensive champagnes, is not ‘Grande Cru’ as it includes some grapes from Hautvilliers where the Abbey that Dom Perignon lived and worked at is situated.  Hautvilliers is not a Grande Cru village so the resulting champagne cannot be called Grande Cru.

Mumm's map of Cru - red = Grand Cru, yellow = Premier Cru and green = Cru.

The grapes are all hand-picked, to avoid damaging the skins, and then pressed within three hours of picking to prevent the dark skins of the pinot noir and pinot meunier from colouring the juice.  The pressing occurs on or near the vineyard, but then the juice is transported to the Champagne House.  The juice is kept separate by grape variety, but also by village, this will allow the Cellar Master to have a large selection of flavours from which to make the champagne.  First, the juice is put into large vats and allowed to undergo the first fermentation.  At most Champagne Houses this is actually two steps – 1) alcoholic fermentation followed by 2) malolactic fermentation.  My experience with alcoholic fermentation always involved adding yeast to the juice to start the process, but I’ve been told that in Champagne, the humidity from the chalk maintains a healthy population of yeast on the grapes, that when pressed enters the juice and will start fermenting all on its own.  Nifty!  Picking happens in a 2-3 week period (that is regulated) and first fermentation can take up to 6 months in stainless steel vats.

Le Grande Foudre - Pommery's mixing barrel circa 1904. It holds the equivalent of 100,000 bottles.

The Cellar Master and a team of tasters will then taste the still wines that they’ve produced, and determine how to blend them to achieve each House’s ideal standard.  Rarely this will involve a handful of wines.  More commonly it is about 50-70 (to as many as 150) different wines, but always of chardonnay, pinot noir and pinot meunier (the amount of each depends on the House and the type of champagne being created).  If there has been an exceptional year the Cellar Master may choose to make a vintage champagne – made of grapes from all one year.  If not then the champagne will be a blend of wines from 3 years – this helps to maintain a constant flavour in an industry that produces slight differences in flavour across years and areas.  Once the wines are blended they are put into champagne bottles with a dose of yeast and sugar and then sealed for the second fermentation.  When yeast eats sugar it creates alcohol and carbon dioxide.  In a tank the carbon dioxide escapes, in a sealed bottle it diffuses into the liquid, and will create the bubbles of champagne when opened later.  The Houses currently use a metal cap for this portion of aging for a variety of reasons (reduce cork wastage, easier with machines) but cork used to be used.  A champagne cork though is about twice the size of the opening of the neck and jamming it in often resulted in broken bottles.  The area used to have their own hand surgeon, to patch people back together from the wide variety of injuries champagne makers suffered, but with technology a specialist surgeon isn’t required in the area any more.

Champagne 'being born' in a gallery at Pommery. The hole is from where a bottle exploded. There is 6 atmospheres of pressure inside the bottles, so sometimes they explode.

The bottles are moved to the caves where eventually, the yeast eats all of the sugar, and then, with no food left it dies and sinks to the bottom of the bottle, creating the lees, or sediment.  This is where a great deal of the flavour comes from.  Champagne left on its lees can be kept for more than one hundred years, it is only if the sediment is removed that aging stops.  To be called a champagne the bottles must be aged for a minimum of 15 months, though three years is more common.  To be called a vintage champagne the legal minimum is 3 years of aging, the actual time will depend on the Champagne House and the Cellar Master it seems to usually be in the 7 year range.  Traditionally there was no way to remove the sediment, so it was strained out when poured or decanted ahead of time.  But with the work of several people, including Madame Cliquot, methods were created to remove it from the bottle.  The first step involves riddling – moving the bottles from their horizontal storage position (most space efficient) to a more vertical position.  By hand this takes 3-4 weeks, and involves turning the bottles slightly each day to slide the sediment into the neck of the bottle.  Good riddlers turn between 40-50,000 bottles per day!  Nowadays however we have machines which are used for all but the best champagnes or very large bottles.

Mold grows naturally in the caves due to the humidity. Don't worry, it's washed off before you get it.

Demonstration at Mumm of how riddling turns the bottle from horizontal to vertical, moving the sediment into the neck.

Once all of the sediment is in the neck of the bottle it can be ‘disgorged’.  Traditionally each bottle would be opened by hand, but this was a precise and delicate procedure as it had to be done just right or 1) the sediment would drift back into the bottle and it would have to be riddled again or 2) half the bottle of champagne would wind up on the floor.  Nowadays the neck of the bottle is dipped into a cooling solution at -26ºC so that an ice cube forms around the sediment.  The bottle is opened, the 6 atmospheres of pressure inside the bottle pops the ice cube out and you have a sediment free champagne.  At this point a ‘liquor de dosage’ is added to make up for the lost volume, the dosage consists of sugar mixed with champagne from the same batch.  The bottles are then recorked and re-stored in the cellars for another three months, to ensure good mixing.  The added cane sugar is what determines if the champagne is brut, sec or demi-sec (dry, medium or sweet).  Brut champagnes have less than 15g of sugar per litre while demi-sec have about 40g.  Traditionally though champagne was served very sweet, about 200g per litre!  Our equivalent today is Coca-Cola.

Champagne at Moet & Chandon.

Then it’s just time to clean the bottle, put the label on, package and ship to happy people around the world!  Now you know more about champagne!

Champagne at Pommery.