The Margaret River wine region is well known for the production of high-quality wines with Cabernet Sauvignon, Chardonnay and aromatic Semillon/Sauvignon Blanc blends the flagship styles.
As with all regions of Australia and New Zealand, many Margaret River wineries are looking to new technologies for greater production efficiencies.
And all the while improving quality as the launching pad for continued growth in the current winemaking economy.
As a result, juice flotation technology is fast becoming the technology of choice for clarification of white juice in the area.
The first juice flotation systems in the region were installed for the 2013 vintage, with many winemakers flagging their main concerns as:
- Refrigeration demands associated with processing white fruit.
- Ever-increasing electricity costs.
- Speed of processing.
- But most importantly the processing of high-solids varieties such as Semillon.
This grape variety in particular can cause many unwanted processing issues due to the high juice solids concentration after pressing.
Most Margaret River winemakers report they have to deal with 20-30 per cent solids volumes before fermentation.
Juice flotation has since proven to be an incredibly useful tool in the technology toolbox for many local wineries by combating or eliminating some or all of these processing hurdles.
Flotation was introduced into the wine industry back in 1988 by the engineering/manufacturing arm of Enologica Vason Group (Verona, Italy) known now as Juclas (Juice Clarification Systems).
But the principles of this technology have been used for decades in many industries such as water treatment and mining.
THE PRINCIPLES OF FLOTATION
While technically flotation is quite a complex operation, in reality its management within the winery environment is very simple.
To summarise the basic principles flotation is a separation technique which exploits the difference in density between solid particles and liquid.
The solids present are made lighter than the must by the surface adsorption of injected gas or air.
The adhesion of the gas to the solids causes a ‘solid-liquid’ cluster with a lower density than the liquid which causes it to separate and rise to the surface (REF).
This process is sped up and made efficient for a winery by forcibly creating floccules by the addition of a ‘flocculent’ such as gelatine or similar colloids with a high electrical charge and high molecular weight.
With this process in conjunction with recommended floccules, the dispersed colloidal particles cluster or flocculate as their hydrophobicity increases.
The dissolved nitrogen or air that’s introduced directly into the juice under pressure carries these floccules to the surface of the must.
And the effect and efficiency of the end result depends on many factors including the surface area of the floccule, surface tension, flow rate, must temperature and importantly the concentration of dissolved gas or air in the must.
Juclas has developed three systems which cover flotation technologies for Australia’s largest and smallest wineries.
These include continuous flotation systems which as the name suggests, continuously floats large volumes of juice.
This consists of large diameter flotation vessels such as the one installed in Marlborough, New Zealand.
Batch Flotation systems are available as single pass systems for large capacity and volume processing such as the setup installed in the Barossa.
Finally, the most commonly sold systems are the Easyfloat portable units with for sizes enabling processing speeds from 5kL/hr to 50kL/hr and starting at just $6500 each.
The Margaret River wine region is fast becoming the juice flotation capital of Western Australia with close to 25 Juclas Easyfloat systems in total to be installed by the end of the 2014 vintage.
Many winemakers have indicated the benefits of juice flotation in white juice processing makes these systems a no-brainer, especially when dealing with the high-solids content common with Semillon where dealing with juice lees volumes with cold settling can be up to 25 per cent.
Now, with flotation and the elimination of the need for static cold settling (as well as must chilling and warming for fermentation), juice lees are mostly around 5 per cent, refrigeration load and associated energy costs are greatly reduced and the RDV filtration of lees is no longer needed, resulting in in faster processing and less down-grading of juice parcels.
Dave Johnson, winemaker for Credaro Family Wines says “the flotation system installed is a fantastic tool for us in white processing.
“We can now have clarified juice ready for inoculation overnight without the heavy refrigeration loads and without compromising juice quality.”
Travis Lemm, the winemaker at Voyager Estate, agrees. He said “the Juclas float unit was a brilliant purchase for the winery; it’s incredibly easy to use and has reduced our production costs significantly.”
Winequip is the exclusive agent for the Juclas flotation technologies and is the industry specialists in this area with close to 100 installations throughout Australia and New Zealand.
Contact: Lee Carty. Phone: Australia on 1300 882 850 or Winequip NZ on 0800 699 599. Email: firstname.lastname@example.org.
R. Ferrarini, M. Bacci, M. Chiodi, E. Celotti (1992), Technological aspects of flotation in clarification and stabilisation of musts and wines, L’enotecnico 7/8, 95-103
R. Ferrarini, R. Zironi, (1992) Flotation technique in winemaking: theoretical principles and plants, L’enotecnico 5, 95-104
R. Ferrarini, R. Zironi, S. Buiatti, E. Celotti (1991), Study on applications of flotation in clarification and stabilisation of musts and wines. Note 1 – effects on must and wine composition. Vignevini 11, 63-67