Wine in South Africa
South Africa’s wine growing tradition goes back several centuries. Napoleon loved the ‘Vin de Constance’ made from Muscat Blanc à Petits Grains (Muscat de Frontignan) grapes grown in the district of Constantia, the oldest wine growing region close to Cape Town.
The landscape of the country with its many arid, dry, but also humid regions is similar to European wine growing regions. The hot and dry climate during summer leads to very different grapes compared with similar varieties in Europe. The grapes which are grown in the dry regions without being irrigated have some characteristics, as for example a thicker skin, which make wine production with conventional processes more difficult. The widely used tank presses cannot process those grapes satisfactorily. However, the HILLER decanter can process them at high yields with high capacity and best juice quality.
This is the reason why the decanter technology is becoming more and more popular in South Africa currently. Within only a few years many decanters for grapes processing have been installed. There are numerous reasons for this. To be mentioned are fast and continuous processing, hygienic operation, the option to adjust for different grapes, the little lees content in the juice and the very high yield of must with A quality.
The cooperative wine cellars “Robertson Winery” in South Africa looks back on a long tradition of wine growing and wine production. They were so satisfied with the Hiller decanter technology that they bought three decanters for their production within only 2 years, from 2013 to 2015. Those Hiller Decanters are now successfully used for grape pressing and lees separation.
Robertson Winery South Africa
The Robertson Winery processes around 37,500 tons of grapes per year. Of this 21,500 tons are white, the remaining part is red. 100% of the finished wine – about 27,000,000 litres per year - are filled into bottles, “bulk wine“ is not produced. Thus each litre has a high value.
In the past the juicing of grapes had been performed conventionally with tank presses. The installation of the HILLER decanter technology now enables a continuous production with significantly less staff required. This change of process has been performed in steps over three years with one additional machine having been added each year: in the first year a decanter for lees preparation was installed. In the second year the first decanter for grapes pressing was added and in the third year now an additional decanter for grapes pressing has been commissioned.
2013: Installation of first HILLER decanter centrifuge for lees separation
Robertson Winery
After extensive tests in preparation in the season 2013 the first food machine of type DF54 for the separation of solids from juice and wine was put into operation.
Replacing the vacuum drum filters, it is now processing floating lees, fermentation lees and fining lees.
It is known that must with a relatively high content of lees is formed by using tank presses. These fines are removed from the must after pressing by flotation or settling and then processed at 100 000 l/day in a combination of the Hiller lees decanter with disk centrifuge. Disk centrifuges on their own could not handle the high lees content. Advantages of the use of the decanter are high savings in filter aids, water and working time and a significantly higher quality of the recycled must or wine.
After the success with that machine the customer decided to buy a second, bigger decanter for grapes de-juicing.
The decanter processes white grapes and in the same way thermo-vinified and conventionally fermentated red wine mash. Here the decanter replaces the pressing systems which were in place before. Throughput and yield vary depending on grape kind and conditions. But compared to normal presses the HILLER food decanter DF76 always reaches higher yields at best quality with low fines content. This makes the winery more flexible for later extensions. Robertson is very happy with the must of the HILLER decanter which is always in premium quality now. Thus no classification into A- and B-qualities, as with tank presses is required, anymore. In all internal tastings, the decanter wine was always among the top 4 of 10 tested wines (5 HILLER and 5 conventional).
Hiller Decanter DF76 at Robertson Winery
In total, the time and energy needed for handling the products (storing, re-storing, pumping, processing) is reduced significantly. In addition the times for pressing and enzyme addition could be shortened to a high degree. The closed system with controllable peeling disc is highly hygienic, flexible and stable in operation. The juice is removed under pressure, so it is transferred to the tank farm without a further pump being necessary.
Currently different decanter systems are on the market. By the closed design with peeling disc, foam formation is not an issue.
In the season 2014, Robertson Winery has already processed a total of 2,000 tons red and 3,500 tons white grapes with the HILLER decanter.
2015: Installation of third big HILLER decanter centrifuge for grape pressing
Hiller Decanter DF76 at Robertson Winery
In January 2015, five big tank presses were replaced by a second food decanter model DF76. It is used for pressing white grapes and runs as efficient, stable and with highest yields as expected.
For Robertson, there is no simpler and more economic alternative to the decanter, as they say. It is the perfect technology for extending capacity. Robertson Winery is very happy with the cooperation and the specific and technical support by UDEC and HILLER.
Summary
The HILLER decanter technology will have a big impact for operation of the wine cellars in the future as it enables a continuous and hygienic process at enormous saving of space, less work being required and above all highest yield of best must – compared with conventional pressing systems. In all cases the final product can go completely into the production of premium wines enabling higher returns.