Saturday, January 8, 2011

Vendemmia Part II "Turning Fruit into Wine"

Well, this is more of a journalistic piece than it is a blog post... but hopefully there is some info here that you may have always wanted to know, and maybe thought you already should know, and so never asked - that's what happened to me in writing it! So sorry for the length, but enjoy, and I promise these 'blog' things will get shorter - if they don't, Peter will fire me!

Winemaking is a very complex, and at the same time simple job. What I mean by this is that wine is a natural process that will happen on it’s own, with little to no interference of man, here is the simple equation:

Sugar + yeast = alcohol + carbonic gas + heat

The science of this process is called enology. It can be said that there are different 'schools' of wine making. There are those that are separated into two roles; the viticulturist, who is specialized in vine growing and harvesting, and who then passes the torch onto the enologist or winemaker who will then control all of the chemical and scientific processes during the winemaking as well as the ageing. Then there are the winemakers/viticulturists, who do not have a degree in enology and will follow the wine themselves its entire journey, from vine to bottle. The 'Indie Wineries' all fall into the latter category. The winemaking of the latter is generally less 'lab dependent' and scientific, and instead uses more traditional methods. This article is a very brief description of wine making that just brushes the surface of the process, and intended to give you all a better idea and general overview of how the grape turns into the glass of wine we love to enjoy! This is also an overview of red winemaking which differs from white wine making, rose and Champagne.

  1. Within a day or two of arriving in the fermentation vessel, which in our case are stainless steel vats, but can also be in some cases wood fermenters, the gently crushed fruit will create a 'cap', which consists of the skins, seeds and pulp, rising to the top and separating from the 'juice' or liquid, and fermentation begins.
  2. Fermentation normally begins at 20 – 32 degrees Celsius, and is caused when the yeasts start to 'eat' the sugar naturally present in the grapes. These yeasts are naturally occurring on the skins of the grapes, as well as in the wine cellars themselves. Some winemakers use 'selected' or 'cultivated' yeasts to have more control over the fermentation, and even adding different taste profiles to the wine. Other natural winemakers will utilize the naturally occurring yeasts striving for a more natural and terrior driven wine.
  3. At the point when fermentation begins the winemaker will begin to intervene, using pump over or punch down, which are two of the methods to reincorporate the cap into the liquid. In essence this is to keep the skins wet and extract color, tannins and flavoring compounds. All of these important parts in a red wine come from the skins, and the immersion of the skins will help 'melt' the skins to bring these factors out, and is referred to as the maceration. This process lasts anywhere from 15 to 20 days.*
  4. When the sugar is all transformed into alcohol, it is time to pull the wine off the cap and the lees (the lees are the dead yeasts that have precipitated to the bottom of the tank). The sugar level can be measured in a lab analysis, or in our case, we use a simple tool called the 'babo'*, in addition to simply tasting the wine.
  5. Pulling the wine off the cap consists of pumping out the liquid, and then putting the cap into a 'balloon' press. This balloon expands inside a cylindrical, perforated, horizontal tube that presses the skins and seeds allowing the last bit of juice to flow out to a receptacle under the press. This juice that is extracted from these skins and seeds is very important because it is the juice that will help to trigger the malolatic fermentation. This wine is added to the rest of the wine that has already been removed, and the skins are bagged and sent to a distillery to become grappa.
  6. After 15 days, or even up to a month of secondary fermentation, the malic acid naturally present in the wine (the 'hard' or 'unpleasant' acids as in green apples), turns to lactic acid (softer, more pleasing acid as in milk). At this point the chemical-physical part of the wine making is complete.
  7. At this point each wine maker will decide what kind of 'ageing' process he or she will use.

The steps above are more or less standard for RED winemaking, and will vary only depending on how a producer uses yeasts, and the amount of time the wine ferments, as well as the type of pump over or punch down the producer does. The more artistic part of the process that makes each producer and each WINE unique after the obvious variables of terrior and variety, is how the producer will age and refine his wine.

Here are just a few examples:
  • Stainless Steel vs. Barrel (size of the barrel and type of wood varies from winemaker to winemaker, and region to region) vs. cement
  • Period of ageing; months, or years
  • Whether the wine will be kept on it's 'lee's' or filtered and/or fined
Too scientific? Not to worry, that is what our talented wine maker friends are for, this is just a small glimpse into the world of winemaking, and all the variables, hard work, and patience that goes into that wonderful glass of wine.

*This year at the Iuli estate the fermentation was slower and lasted longer than normal… some tanks up to 25 days. For us this is a positive thing because the longer fermentations can produce more elegant wines. Producing wines naturally without or little temperature control and without selected yeasts, there is little to no control over the fermentation lengths or no real solid reason why some tanks ferment slower and some other tanks faster. It is all part of the magic of winemaking…

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