Brettanomyces bruxellensis prevalence in wines produced and marketed in Spain

Abstract

The sensory deterioration of wine caused by the formation of volatile phenols (4-ethylphenol and 4-ethylguaiacol) due to the growth of the spoilage yeast Brettanomyces during the winemaking process can cause serious financial loss and problems in export trade barriers. The presence of this microorganism is increasingly common in cellars. Fast, specific and early detection of this yeast during wine production enables the oenologist and producer to take preventive measures before the phenolic aspect appears. Several methods are available for the detection of this yeast species. A new, quick and easy-touse kit based on RT-PCR to detect Brettanomyces has appeared recently on the market. To evaluate the prevalence of this microorganism in our country and the effectiveness of this new technique, we analysed 86 red wines produced and marketed in Spain (commercialised wines or just before being bottled). We compared the results with those obtained with traditional microbial counting on selective medium and with another molecular method based on the amplification of the internal transcribed spacers (ITS1 and ITS2) of the rRNA 5.8S. Fifteen samples (17.4%) were positive for the presence of B. bruxellensis by microbiological plate counting after 5-7 days of incubation and 14 (16.3%) also gave positive results with RT-PCR analysis, after only 7 h. Of 86 wines analysed, 16 (18.6%) were positive with at least one of the methods used.

Detection of Brettanomyces spp. in Red Wines Using Real‐Time PCR

“…In fact, 12 samples resulted to be positive when analyzed by qPCR and negative by plate count. Similar results were obtained by Campolongo and others (2010) and Puig and others (2011) in studies conducted on wine samples from northwestern Italy and Spain: also in these cases Brettanomyces spp. was mainly detected using a culture‐independent approach.…”

Metabolism of Nonesterified and Esterified Hydroxycinnamic Acids in Red Wines by Brettanomyces bruxellensis

“…Brettanomyces has been regarded by some as the most severe microbiological threat to wine quality causing serious financial losses each year . As part of its metabolism, Brettanomyces utilizes hydroxycinnamic acids to produce ethylphenols (i.e., volatile phenols) which have been sensorily described as “barnyard,” “leather,” “horse sweat,” and others. − Biochemically, the hydroxycinnamic acids are first decarboxylated into vinylphenols, which are subsequently reduced to ethylphenols. , Biosynthesis is dependent on many factors including the strain and energy source such as glucose or ethanol. − …”

Effect of kaolin silver complex on the control of populations of Brettanomyces and acetic acid bacteria in wine

“…Nonetheless, a smaller population (between 1 and 1.5 log units) was found on day 24 in treated wines, while the control maintained the same initial population at 24 days. It should be mentioned that it is very difficult to find such high populations of B. bruxellensis in real conditions, in naturally contaminated wines (Puig et al 2011). In these cases, the results indicate that perhaps it would be necessary to treat the wines with doses of KAgC over 1 g/L.…”