Research highlights Chile’s potential

Research by Chilean producer Viña Casa Silva has yielded results which could see dramatic changes in the country’s vineyard management and wine quality.

The three year study was carried out in partnership with Professor Yerko Moreno, director of grape and wine research at the University of Talca. The aim of the project was to establish why vines grown under apparently similar conditions in the same vineyard were displaying different quality potentials.

In total, the team studied 90 micro-terroir plots, planted with five different varieties at Viña Casa Silva’s estates at Los Lingues in the Andes foothills and Lolol in the coastal shadow. Having vinified these samples separately in 500 litre barrels, the tasting panel then compared the individual characters of these wines with extensive data gathered from each site.

Based on statistical analysis, the team identified the four most important influencing factors in the vineyard: the average January temperature, spring rainfall, root depth and soil moisture content. Soil composition was shown to have a more significant impact on grape quality than either climatic factors or viticultural methods.

As a result of these findings, Viña Casa Silva has now drawn up a blueprint, enabling it to reorganise the layout of the vineyards and re-graft those vines which were under-performing. “For a winemaker this is the holy grail!” commented Mario Geisse, head winemaker at Viña Casa Silva. He added: “We are now able to select precise mini-parcels of each variety for our best wines, adapt our vineyard management according to the needs of each individual plot and micro-vinify to get the best possible quality wines.”

Based on questions raised during this initial reseach, a further two year project is now being carried out to investigate some of the problems posed for winemakers by Carménère. Achieving higher fertility and lower levels of Pyrazine, the chemical responsible for the variety’s characteristic greenness, are both high on the agenda for developing better quality examples of this important Chilean grape.

Mario Pablo Silva, managing director of Viña Casa Silva, highlights the reason for his particular interest in this variety, saying: “Cabernet Sauvignon continues to be important for Chile in terms of volume, but we trust that Carménère will have a very good association with quality wines. The industry is placing Carménère as very important to the future of Chile and the consumer is responding to this.”

Already, its initial findings have led Viña Casa Silva to begin picking its Carménère grapes a whole month ahead of its rather suspicious neighbours. The more usual approach is to leave the grapes longer on the vine to diminish some of its natural green character; however Moreno believes: “You can harvest Carménère early if you treat it properly in the vineyard.” At Viña Casa Silva, this means keeping the vine canopies alive until very late in the growing season and also maintaining irrigation for longer.

Speaking about the motivation behind this pioneering viticultural approach, Silva explains: “We really want to use this as a philosophy and in practice as well; and perhaps other wineries will use it too.”

And that’s not the only pioneering in the pipeline. Viña Casa Silva has just launched its first wine, Culcos, from a new site in Paredones, which represents Colchagua’s first coastal vineyards. Further plans are afoot for the release of Sauvignon Blanc, Pinot Noir and Chardonnay from the exceptionally cool Lago Ranco area of Chilean Patagonia.

The untapped potential of Chile as a wine producer is recognised by many experts, but Viña Casa Silva is certainly pushing the boundaries further than most.

Gabriel Savage, 14.10.2009