Real-time Genetic Detection of Spoilage Organisms in Juice New Capabilities
Targeting Specific Spoilage Microorganisms
- Despite the best practice of modern winemaking methods, microbial contamination often occurs prior to wine production.
- The spoilage microbes are capable of survival and growth in both the juice and wine, potentially producing off-flavors, off-aromas, and turbidity.
- Microbiological contamination is often undetected until related problems in the wine become noticeable by sensory evaluation.
- ETS now offers Scorpions™ assays, based on specific genetic markers, to detect wine and juice spoilage organisms.
- This new, genetic analysis detects microbial populations directly in wine or juice. Results are routinely reported within two business days – giving winemakers the ability to address problems before wine defects occur.
- ETS has developed a series of Scorpions™ assays to provide winemakers a tool for rapid identification and quantitation of spoilage microbes in their wines.
- The assays utilize a combination of gene amplification and hybridization to accurately quantify the total number of viable cells in a sample.
Used separately, or in combination, ETS Scorpions™ Panels enable the winemaker to specifically monitor those organisms that pose a threat to the quality of their individual wines, including: Brettanomyces
is widely distributed in winery environments. They produce high concentrations of volatile acids, esters, and the volatile phenols 4-ethylphenol (4-EP) and 4-ethylguaiacol (4-EG). These volatile phenols are largely responsible for off-flavors or taint associated with Brettanomyces. Zygosaccharomyces
is a spoilage yeast that is tolerant of high sugar concentrations and is resistant to sorbate. It is commonly found throughout the winery environment and is often associated with grape juice concentrates that are used to adjust color and sugar in final wine blends. The yeast can cause turbidity and CO2
gas in bottled wines. Pichia
is a wild yeast that is often present at high levels on incoming fruit. Pichia can initiate fermentation, resulting in production of high levels of volatile acids, including acetic acid and ethyl acetate. These yeast have been associated with films formed in barrels and tanks during storage. Hanseniaspora
Hanseniaspora is a wild apiculate yeast that is often present at high levels on incoming fruit. Hanseniaspora can initiate fermentation in the must and produce high levels of volatile acids, including acetic acid and ethyl acetate. It has been associated with acid rot in grapes infected by Botrytis cinerea
. Population levels usually decline as alcohol concentration increases. Pediococcus
is one of the common malolactic bacteria found in wine. They may produce polysaccharides that cause undesirable texture defects. Pediococcus are unusually adept at generating biogenic amines, such as histamine putrescine and cadaverine. . Although biogenic amines are not currently regulated in the United States, legislation in the European Union, Australia and Switzerland is a forewarning of future export hurdles. Lactobacillus
is another malolactic bacteria commonly found in wine. They may produce high concentrations of diacetyl often causing undesired buttery flavors. Lactobacillus is also notorious for producing acetic acid in a short period of time – often in a matter of a few days. This can occur readily during sluggish or stuck fermentations. These bacteria have also been implicated in the production of mousy flavor. Acetic acid bacteria
are commonly associated with grapes and the winery environment. The two groups of acetic acid bacteria detected are Gluconobacter and Acetobacter. These bacteria can generate acetic acid in the absence of SO2
and in the presence of oxygen. These organisms can cause elevated volatile acidity in wines exposed to air. The presence of acetic acid bacteria indicates that wine conditions may support the growth and activity of other spoilage yeast and bacteria.
What Advantages Does Gene Specific Analysis Offer?
Juice Spoilage Panel
Acetobacter and Gluconobacter
|A.pasteurianus, A.aceti, G.oxydans |
|P.damnosus, P.parvulus |
|L.brevis, L.hilgardii, L plantarum |
|Brettanomyces ||B.bruxellensis, B.anomala |
|Pichia||P.membranifaciens, P.kluyveri, P.fermentans|
|Hanseniaspora (Kloeckera)||H.uvarum, H.valbyensis |
There are several advantages of genetic analysis as compared to traditional plating methods.
Time to results - Standard time to results for Scorpions™ is 2 working days.
Detects Viable but Nonculturable (VNC) organisms - Most wine spoilage microbes can survive in a VNC state under the combined stress of SO2
, pH, and alcohol. As the SO2
levels drop in the bottle, these organisms can resume growth, resulting in wine spoilage.
Specific identification- Scorpions™ technology is highly specific to the target organism, requiring three exact DNA sequences, aligned and spaced properly, to detect the target organism. This enables identification to species for all of the wine spoilage microbes.
Proactive use of Scorpions™ technology enables early detection of wine spoilage microbes. Early detection enables the winemaker to intervene, preventing spoilage and preserving quality. This is especially important in the early stages of the winemaking process where time is critical. This document is a compilation of information and views from various sources provided for the convenience of our clients. Information in this document is provided "as is" without warranty of any kind, either expressed or implied, including but not limited to the warranties of merchantability, fitness for a particular purpose and freedom from infringement. User assumes the entire risk as to the accuracy and the use of this document. This document may be copied and distributed subject to the following conditions: 1) All text must be copied without modification and all pages must be included; 2) All copies must contain ETS's copyright notice and any other notices provided therein; and 3) This document may not be distributed for profit. All trademarks are acknowledged. Copyright ETS Laboratories 2001-2013.