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CO VER S T OR Y fungus, produces enzymes (Laccase) that oxidize phenolic compounds, resulting in premature browning in white wines and color degradation in red wines. Detection is based on the immunological principle of antibodies produced in response to a specific Botrytis antigen and measured on a percentage-rot scale. Certainly the analyses offered by ETS and Enartis Vinquiry for grape, juice and must evaluation are comprehensive and provide well-needed information to the winemaker. What other tests are being ordered by winemakers during harvest? ETS' top five Gordon Burns and staff at ETS Labo- ratories provided Wines & Vines with their top five requested non-juice panel analyses: Laccase, IBMP, grape moisture content, rapid phenolic panel and juice yeast and bacterial spoilage panel. Early detection of Laccase levels in grape juice allows the winemaker to take corrective and protective measures for infected juice. (See "Ignoble Rot in Cali- fornia" in the May 2012 issue of Wines & Vines.) IBMP stands for 3-isobutyl-2-me- thoxypyrazine, an extremely potent flavor compound with the aroma of green bell pepper. IBMP levels decrease in berries as they mature and are often used as an indicator of when to pick. Once the grapes are harvested, the level of IBMP is difficult to alter and will directly influence the final levels in wine. Grape moisture content reflects the hydration conditions of the berries and is used to estimate juice yield as well as providing continued information for vine- yard practices. Dehydration leads to the concentration of compounds and grape- receiving issues for winemakers. Rapid phenolic panels evaluate the potential phenolic composition of ber- ries, clusters or juice including cat- echins, polymeric anthocyanins, total anthocyanins and tannins. Results are reported in 48 hours, allowing wine- makers time for tannin management and other adjustments. The juice yeast and bacterial spoilage panel via the Scorpion genetically identi- fies yeast and bacteria that may cause undesired characteristics, increased VA or compete with Saccharomyces for nu- trients creating problem fermentations. Some of the organisms identified are: Acetobacter, Gluconobacter, Lactobacil- lus, Pediococcus, Brettanomyces, Hanse- niaspora, Pichia and Zygosaccharomyces. The ETS Scorpion Volatile Acidity Juice Panel offers fast identification of bacterial and yeast spoilage organisms such as Acetobacter, Lactobacillus, Botrytis and Brettanomyces. Enartis Vinquiry's analyses Don Frazer, consulting winemaker for En- artis Vinquiry's Technical Services, shared his priorities for harvest-time lab analyses, starting with the fruit on the vine. "Ideally you want to adjust (pH) in the vineyard," he said. In addition to the core juice panel, the Enartis Vinquiry potassium analysis and organic acid profile provide beneficial data for making long-term pH adjustments in the vineyard. Frazer pointed out that to make acid adjust- ments in the winery, using the predictive acid panel will help with additions and estimating the final post-secondary malo- lactic fermentation pH. Some additional analyses Frazer men- tioned were percent solids for white juice (especially machine-picked), which tend to have higher solids levels and a juice evaluation for bacteria and yeast via gene sequencing when performing non-Saccha- romyces-inoculated fermentations. Although Enartis Vinquiry does not perform phenolic analysis on juice or must, Frazer advised that following the data obtained during fermentation and on post-fermentation red wine is a useful tool, especially when the data from a par- ticular varietal can be compared to other results from the same varietal, region or AVA. He was referring to the wine pheno- lic fingerprint panel. The wine phenolic fingerprint panel is a fast, quantitative measurement of pheno- lics that includes total tannin, total phe- nolics, total pigment, free anthocyanins and pigmented tannins. This quantitative measurement was developed by The Aus- tralian Wine Research Institute (AWRI) and is a spectral calibration predictive model using six UV-Vis absorbance read- ings. It is based on the Methyl Cellulose Precipitable Method (MCP), but the re- sults are in line with the common Adams/ Harbertson Assay. The AWRI has opened a web-based application, "The AWRI Tannin Portal," which allows the user to enter absorbance readings from their spectrophotometer into the web interface and returns the results immediately. Users can then benchmark their data against the AWRI database. Contingency analyses Frazer recom- mended include the botrytis risk assess- ment if the fruit is damaged "and if the year calls for it, Laccase and Glucans." "Glucans will need an enzyme (Beta- glucanase) to break them down, but Laccase needs flash pasteurization, which most wineries don't do; instead, us- ing some tannin may work, plus time." Frazer added that proper SO2 and oxygen management is a must. Damaged fruit can often bring in Brettanomyces, and Frazer recommended a yeast evaluation, although he says, "There are two kinds of wineries…wineries that have Brett and those that don't know it yet." Frazer pointed out that with damaged fruit, good sanitation, advanced plan- ning and proper winery practices are paramount in controlling both Botrytis and Brettanomyces. WINES & VINES OCTOBER 2012 27