Definition: Yeast included (agglomerated yeast)

When the yeasts have finished this transformation process, they die, one might think, from a deep alcoholic coma! As their density is greater than that of wine, these corpses sink to the bottom of the vats or barrels to join the coarse lees. In the vinification of still wines, racking and possible filtration are sufficient to make the wine perfectly clear. For more than three centuries, the modern Champagne method has consisted of adding sugar and yeast to a still wine before bottling. It is in this closed environment that a second fermentation begins. The carbon dioxide and dead yeast are trapped. A fairly large deposit (about one cubic centimetre), clearly visible to the naked eye, forms in the bottle. This deposit does not remain suspended in the wine. It sinks, but tends to stick to the glass of the bottle. Until 1815, when Veuve Clicquot invented the riddling table, these impurities were removed by decanting, i.e. by transferring the wine from one bottle to another, resulting in a significant loss of carbon dioxide. From 1840 onwards, the riddling racks that we still use today became widespread. For two to three weeks (formerly two to three months), the riddler subjects the bottles, with their bottoms facing upwards, to a partial, sharp rotating movement, while gradually straightening the bottle. This technique causes the sediment to detach from the glass and descend towards the neck. It is at this point that disgorging takes place. The bottle was uncorked with a sharp movement so that, under the effect of the gas, the sediment was expelled with as little of the precious liquid as possible. This manual disgorging is now a thing of the past. Since the middle of the last century, disgorging has been mechanised. The neck of the bottle is immersed in a refrigerant liquid. An ice plug forms inside, trapping the dead yeast. This plug is expelled when the bottle is uncorked. From 1970 onwards, manual riddling was gradually replaced by a gyropalette system containing a large number of bottles (504 standard bottles - 216 magnums). In these large metal cages, the bottles are subjected to the same movements as those performed by the riddler, reproduced electronically.

This history shows that riddling and disgorging have evolved considerably. Experience now shows that, with this technical advance, there is virtually no difference in the quality of champagne. Only the beauty of the riddler's gesture has been lost. It should be noted, however, that, for reasons that are not fully understood, some vintages are easier to riddle than others. In general, a special fining agent is added to the liqueur de tirage to facilitate riddling, and different types of fining agents are used depending on the type of deposit desired (flaky or compact).

Since the mid-1980s, numerous experiments have been carried out in collaboration with the technical departments of the Comité Interprofessionnel du Vin de Champagne, the Institut Œnologique de Champagne and Moët & Chandon, involving a brand new process of enclosed yeasts, also known as the bead technique. The yeasts are enclosed in an alginate bead (extracted from seaweed). This bead is porous, so the yeasts' appetite for sugar remains and they transform it quite normally. Alginate does not stick to glass. This major advantage means that the bottle can be left on its tip for just a few hours, and the deposit concentrates in the neck, close to the cork. This saves time and space, as the racks take up a huge amount of space, and handling is greatly reduced. This new technique, which was quickly developed, encountered difficulties when it came to applying it to large volumes. It is difficult to control the exact number of beads introduced into each bottle: too many beads and the pressure causes the bottle to explode; too few beads and there is insufficient foam. These technical problems have now been solved and nearly 4% of Moët & Chandon's volume (2002) is produced using this method, with no significant difference in taste between these bottles and others produced using the traditional riddling method. In the future, other houses will use this process or something similar. Pommery is conducting experimental research with agglomerating yeasts that have the property of sticking together to form an agglomerate that is easier to disgorge. Other avenues are being explored, such as enclosing the yeasts in a kind of net attached to the cork. Clearly, the poetry of the Champagne method is taking a hit!

The Champagne Oenological Institute also provides custom services (cold treatment, filtration, bottling) and has just acquired equipment for disgorging and bottling large bottles, in anticipation of the ban on decanting for jeroboams.

Purists argue that, in Champagne, when seeking complex wines, alginate beads are not as reliable or effective a solution as the lees, which transform gradually during ageing on racks. It should be noted that this technique has been developed mainly by sparkling wine producers, particularly in Spain. Due to a lack of acidity compared to Champagne wines, cava has a very short shelf life. The structure of the wine requires the process to be activated, and the second fermentation in the bottle ultimately adds nothing but bubbles. The use of alginate beads considerably reduces the riddling time, to a maximum of 48 hours in large production units on the east coast. In conclusion, it will take a few years and further technical advances before we can judge the effectiveness of this method.