Monday, 3 February 2014

Nothing Goes to Waste

As I enter the third week of my vintage experience, the pieces of the puzzle are all slowly starting to fall into place.  My dayshift counterpart, Gracie, and I have been left to our own devices to run the yeast area of the cellar and we are starting to establish some form of a routine, despite the constant multi-tasking required.

Working in the yeast area, I have come to appreciate that nothing goes to waste in the winery.  Last week, I described the first racking, undertaken to separate the clear grape juice from the skins, seeds and pulp.

Now, the lees still contain a significant amount of good juice which can be extracted.  This is achieved using a Rotary Disc Vacuum Filter (RDV), which is lovingly known as the 'Poo Wheel'.  

The 'Poo Wheel'
In basic terms, this is how the RDV works:
1. The lees are pumped into a 'bath' at the bottom of a large, rotating cylinder
2. The cylinder contains a filter 'skin' and is also coated with a fine powder which assists in collecting solids
3. A vacuum system is used to draw the lees from the bath and through the filter
4. Liquid grape juice passes through the filter for collection whilst solid material clings to the outside of the cylinder and is collected in a disposal bin

Vacuum Filtration

And where do the two RDC products end up?
  • The solids are collected and utilised as mulch for the vineyards
  • The collected juices are pumped to the yeast area and separated into 1000L and 2000L tanks in preparation for breeding yeast cultures