South Africa Wine Technical Yearbook 2025

prefermentative stages of the winemaking process, either on the grapes or at tank filling. 5.1 Recurrent grape block contamination In a winery in Columbia Gorge AVA, WA, USA, recurrent Brettanomyces

issues have been identified as coming from grapes grown in a specific block of their vineyard. A trial was done with 50% destemmed bunches of Syrah from this identified block and homogenously filled in 40 hL oak tanks (same provider, same age). As

the elevator moved fruit into tank, 4 g/hL of SO 2 were added in both cases. Then, LEVEL 2 SALVA™ was inoculated in one tank compared to the control tank with no addition. Tanks were not mixed for 24 hours at 14°C, before the Saccharomyces cerevisiae

FIGURE 7. Brettanomyces population in wines after MLF. Winery trial on Tempranillo, Spain. Comparison between LEVEL 2 SALVA™ inoculated by spraying on grapes and a control with no treatment.

FIGURE 6. End MLF analysis. Winery trial, Syrah, Columbia Gorge AVA, United States.

FIGURE 8. Volatile phenol production in Rebo must with and without LEVEL 2 SALVA™ at the end of alcoholic fermentation.

FIGURE 9. Volatile phenols measured in a Cabernet Franc (Università Degli Studi di Udine, Italy) with no SO 2 , with SO 2 addition and without SO 2 but with LEVEL 2 SALVA™.

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TECHNICAL YEARBOOK 2025