The clock is ticking! After a better than expected summer it looks like the harvest of the grapes for this year’s Beaujolais Nouveau may start a little early at around the 15th of September. This still gives just nine short weeks to complete all of the fermentation and get it into bottles ready to pop the corks on the 17th of November – 2016’s Beaujolais Nouveau day.
There is a slight misconception that all the wines of Beaujolais are designed to be drunk immediately and are rushed to the shops as soon as they are ready. In fact the majority of the region’s wines are quality reds that need to be aged to give good drinking.
The Beaujolais Nouveau is a very special wine that exploits some very clever wine chemistry in order to produce a red wine that can be enjoyed little more than a couple of months after the grapes have left the vines.
Another misconception is that black grapes produce red juice for red wine. This is definitely not the case – a large amount of champagne, for example, is made from black pinot noir grapes. Red grapes produce white juice just like white grapes. However, instead of extracting the juice from the rest of the pulp after crushing the grapes, red wines are usually fermented as a pulp, keeping the crushed skins in contact with the fermenting grape juice extracts the red colour (and a whole bunch of other chemicals) and produces red wine.
The red colour comes from a class of chemicals called anthocyanins (which comes from the Greek anthos – meaning flower and cuanos – meaning dark blue). These complex organic molecules seep slowly out of the grape skins along with other phenolic compounds such as flavanols and flavonoids. These even look like proper chemistry – groups of hexagonal rings joined together with all manner of other groups dangling off their corners. These complicated chemicals are what are collectively known as tannins (so called because of the ability of such compounds to preserve – or tan – animal hides) and give the bitter and astringent sensations that make very young (or just bad…) red wines undrinkable.
So, what’s all this got to do with Beaujolais Nouveau? Well, because of the way that tannins work, most Beaujolais wines would be pretty awful if you tried drinking them just nine weeks after picking the grapes. As red wines age, the anthocyanins and other tannins polymerise – they join together to give longer, even more complicated molecules. This has several effects: it removes the bitterness associated with the smaller tannins and gives a more complex and rounded flavour; It deepens the red colour but will eventually start to pale and introduce shades of brown; It also increases viscosity and mouth feel and gives the wine what is often referred to as ‘body’.
But this still doesn’t help with our nine week old Beaujolais Nouveau!
So this is where the clever wine chemistry comes in. Beaujolais Nouveau is a vin de primeur – the description of many wines that are designed to be consumed during the year of their growth. Rather than crushing the grapes to release the juice, the Gamay grapes used for Beaujolais Nouveau are kept whole and sealed in an airtight vat in which the air is displaced by carbon dioxide. Traditionally this would come from the fermentation of the grapes at the bottom of the vessel which get crushed under the weight of those above them – but these days there may also be some deliberate help to purge the system before sealing.
The carbon dioxide permeates the skin of the grapes and stimulates fermentation within the cells of the fruit. This is also referred to as whole berry fermentation – the wine is made within the grapes without them needing to be crushed.
The result of this clever bit of chemistry is that you produce a very light and fruity red wine which is very low in bitter tannins. This is useless for ageing because there’s nothing in there to develop the complexity that you want as a payback for keeping your wine untouched for so long. But, for drinking immediately it means that you get a wonderfully light and fruity wine without the bitterness and without the need for all of that boring patience!
These days, you can do a PhD in wine chemistry (check out the programs at Australian universities!). Having just spent six months analysing the flavour compounds in wines, I can confirm that this is an incredibly difficult subject. (More on this in early November). The Holy Grail of wine chemistry is to find a way of accelerating the ageing process to achieve the results of six years’ perfect ageing in six to twelve months (the complete opposite of the cosmetics industry…). The wine makers in Beaujolais have already achieved the next best thing – using clever chemistry to achieve a perfectly drinkable wine in six to twelve weeks. Even cleverer – they’ve executed a marketing coup that has everyone wanting to drink their wine on the day that it is released – just because they can!