Tuesday 15 September 2009

WSET 8/9/09 Lesson 1 part 2

The senses are being tuned, so how about the wine?


 Now I could have gone a right old rant after grabbing a bottle on the way home from last week's class from Martin McColl, only to get it home to find it had already started the journey to making a lovely red wine based soup whilst being stored for sale. Heat & any wine ain't a good situation whilst it's still in the bottle.

This beautiful shot of a natural cave cellar in Bekaa, Lebanon isn't available in every dwelling. The environment that the wine is stored in is very important for its preservation.

Wine, obviously, is stored in all sorts of larger vessels whilst in production, however when finished it needs to be transported. A lot of progress has been made over the centuries in the vessels that wine is stored in. From the pottery, leather, wood or metal vessels in ancient history through various bottle shapes, many looking remarkably like modern port decanters, through to the now almost universal 75cl glass bottle. Here there is a great range of shapes that almost always in the old world are synonymous with a specific region. I will be learning region by region further along in the course, so will get to grips with the whys & wherefores of that along with the tastings of the regions. When on holiday in Var it's always fun to take along the 4 litre plastic container to fill up petrol station style with the local young rosé, but this container is only good for wine you're having within a day or 2.

Long term storage of wine is always done in bottle, & has been for a couple of centuries. These generally are in a dark coloured glass to keep light away from the wine, though for younger wines, often the whites & rosés, the glass is now clear to allow the drinker to see the colour of the wine. The bottle needs a closure of some kind to keep the air out & wine in. For the last few centuries this has generally been cork. Cork was a good solution in terms of success then, now it is being agreed nearly universally that cork itself presents too many problems to be the ongoing number 1 closure of choice.

Cork is a natural product. It is harvested by stripping the bark from the Quercus Suber, a sort of oak. This process doesn't harm the tree & is repeated every 9 years from the tree's 25th year. The tree only grows in certain climates, between 100m & 300m above sea level; annual rainfall between 400 & 800mm; temperatures never falling below -5ºC. The coastal margins of the Mediterranean have traditionally seen it grown, though areas of the new world are put aside to its production. Cataluña had been the centre for its production. It still remains a major producer, but during the Spanish civil war Portugal stepped in to become the European cork producer, now growing 30% of that market. With much of the manufacturing process centred south of Oporto, Portugal now processes 50% of the world's cork. Much imported from the European western Mediterranean & also north African regions. Algeria having been Cataluña's major rival before cultural shifts there in 1960's.

Cork goes through various processes before becoming a stopper. Cork is porous, so is cut at 90º to the growth to minimise any gaps. Bacterias & fungi are present in its structure, to help kill these it has been bleached with chlorine based bleaches. Other processes are now being explored, the major reason being the presence of TRICHLOROANISOLE. This compound will probably be cork's final undoing as it has been found that the bleaching isn't where it becomes present. Despite this drawback there is much in cork's favour; the trees are an environmental bonus, their acorns a cornerstone in feeding the finer end of pig farming; 90% of the time they form a perfectly good barrier for keeping the wine in; they are flexible, so when factors unfavourable to the wines good storage cause the wine to expand or contract the cork maintains the air seal. The major rival now to cork is the STELVIN, steel-vin (wine), screw-top favoured by many a British supermarket, or the synthetic, plastic, cork. Occasionally glass stoppers are used, there are all sorts of pros & cons for all the closures. Progress, research & development continues on all of them.

Transport is obviously never going to be a friend to wine, but the minimum of heat, light & vibration during this is a bonus. Bottles are good for this, but it is often during transport that any of the closures are compromised. The stelvin has an Achilles heel in that a strong knock can break its integrity so making a hole letting wine out & air in, or even a momentary loss of air seal that lets air in. To this end more finished wine is transported in bulk containers & bottled at, or near to, the country of sale. I am looking forward to a visit to Constellation's Avonmouth bottling plant in 2 weeks time. Bulk transport actually is good for wine, however I will be putting in a link here where the provenance of some wines has been 'flexed' due to political market forces in the Balkans.

So the wine's in the bottle. It has a closure. Now where is it going? The cellar! I don't have a lovely cave for my wine, nor do most of us. The key thing for wine storage isn't the appearance, but stability.

Cool & constant; within a temperature range of 10º to 15º, not within a day, but within a year. Cellars had obviously been the best for this as the ground worked as a great insulator to the day's & season's changes. It is the expansion & contraction of the wine that pushes & pulls on the closure that crucifies most wine. Constant refrigeration is bad too as it causes corks to contract. That air-seal integrity is what is paramount for maturation of many a stored wine. In the age of climate control the storage cabinets that can be placed anywhere that allow wine to be stored longterm where no cellars are available.

Lying down; for bottles under cork, the wine stops the cork drying out, so doesn't contract, maintaining that air-seal. The problem here is if the cork has any nasties in it then they are going to get into the wine. The damp nature of cellars again being a bonus for keeping the airside of the cork moist. With the modern closures of stelvin, synthetic & glass the reverse applies. Bottles are stored upright without the wine in contact with closure, so minimising any potential contamination from it. The synthetic is still viewed with suspicion in certain circles for its potential tainting by long contact with the wine, so it may become disregarded for long term storage. Stelvins have had extensive ongoing research & development into their ability to be complete or breathable seal for the long term storage of wines.

Darkness; natural & artificial light adversely affect wine. Not only does it cause heat, but light can cause unwanted chemical reactions in the bottle. This is why traditionally wine bottles were dark coloured. Wines served young obviously don't hang around long enough for the presence of light to affect them, so hence the ever increasingly light coloured or clear glass bottles around as we drink more young wines.

Vibrations; not for imbuing an extra cosmic element to the wine, but the wine should be still. Changes go on with wines made for maturing in bottle that cause particles to form in suspension, these either should remain motionless there, or should settle out. Railway arches or old freight yards near still operating lines, or depots near major roads, are not the best places for long term wine storage, despite the arches having other cellar-like bonuses.

Most of us aren't in the privileged position to be laying down fine wines to mature for a number of years or decades, or to be choosing which part of the cellar has the least light for the re-building of the racking. Many of us are storing wine for a while though & so often it's in the kitchen, which couldn't be more unsuitable as cooking causes the temperature to sore & plummet. Lounges are often poor homes too if they have heating or fires. Funnily it's the hoover cupboard under the stairs off of the un-heated hallway that wins in most modern homes.

I'm off again to heat up my kitchen for some lunch. Next blog will have getting the wine out of the bottle at the right temperature, into the right glass, then a little on how to keep it happy if it's being saved for later.

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