Info Mine - Yeast

The Wine Mine Blagging Toolkit - 5 wine nuggets with which to impress your friends...

1. The job of yeasts in wine production is to metabolise carbohydrates - that's "turn sugar into alcohol" to you and me. So yeasts are the agents of fermentation.

2. Although the primary purpose of yeasts is fermentation, they can also impart certain flavours to the wine, especially as lees (see 3 below).

3. Once the fermentation gets to about 18% abv, the yeasts die, turning into lees - dead yeast cells. Lees can also be produced (i.e. yeast can die) due to lack of sugar and nutrients. Wines which remain in contact with their lees for a substantial amount of time have a richer, creamier texture and biscuity/bready flavours (they are sometimes called sur lie wines). This is an established technique used in champagne production. Other examples include some white burgundies and some Galician wines.

4. Following lees contact, wines will be cloudy with suspended particles. There are various ways of clarifying the wine, including filtering, racking (allowing the dead yeast cells to sink to the bottom of the tank, then gently pouring the clear wine off) and fining (adding substances which attract solid particles and proteins - traditionally egg whites and ox blood, but also bentonite and synthetic chemicals).

5. In new fermentation vats/wineries, yeasts may have to be added to the must (fermenting grape juice) to kick-start fermentation. In older set-ups there will be enough yeast in the atmosphere for this process to start of its own accord.

(For yeast in sherry making, see post on flor.)

Life of a Salesman

First published on Harpers' TalkingDrinks website on 17 November 2008 - see here.

"We're adding a little something to this month's sales contest. As you all know, first prize is a Cadillac Eldorado. Second prize is a set of steak knives. Third prize is you're fired."

With these words Alec Baldwin's character scares the life out of his sales force in the classic 1992 film Glengarry Glen Ross. Forget performance-related bonuses and share options, this is one way to incentivise your employees that gets the message across.

Things may not be quite this bad for the UK's wine salesmen and women but it's instructive to watch how the current economic doom makes us sit up and pay attention. It was all mildly entertaining when it was about bankers leaving Canary Wharf with cardboard boxes and stunned expressions, but now the crunch has turned into a crisis/catastrophe/cataclysm and threatens our pockets and - shock horror - our jobs, it is no longer a laughing matter.

The idea of this weekly blog is to give a personal view of the wonderful world of wine, mixing in some news and observations in what I hope will be a coherent way. I'll try not to go on about the credit crunch too much - I think I speak for us all when I say it makes for rather depressing reading.

Starting with something a bit more upbeat then, last week's big trade tasting was the Farr Vintners 2008 Christmas Tasting at Vintner's Hall. On show were Krug's and Dom Perignon's rosés - both good but do they really deserve their enormous price tags? The Domaine de Chevalier Blanc 2002, billed by Farr as "Bordeaux's answer to Grand Cru white Burgundy", was a fantastic example of the top class whites that Bordeaux can produce. The Clos du Marquis 2000, the second wine of Leoville Las Cases, promised great things (it has been described by Robert Parker as "one of the great sleepers of the vintage"). Of the Vins Doux Naturels, the 1956 Rivesaltes (Cave de Rivesaltes) was the pick of the bunch and remains surprisingly fresh.