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July 2016 WINES&VINES 37 PRACTICAL WINERY & VINEYARD WINEMAKING clearly different biochemical characteristics. Producers of wine LAB cultures took advan- tage of "strain typing" to classify the organ- isms in culture collections and control their production. Academic enologists and production winemakers used strain typing to control the implantation of inoculated organisms. Poly- merase chain reaction (PCR) protocols were developed to detect Brettanomyces bruxel- lensis and other spoilage bacteria; they are specific, sensitive, reliable and affordable. Future research into the microbiology of wine will be through the study of microbial genomes in association with physiological and metabolic studies under conditions re- flective of wine parameters. For selected wine LAB starter cultures, the crucial ques- tion deals with their survival after inocula- tion into wine. Research in the 1990s clearly identified the deleterious effects of low pH, alcohol, fatty acids and other toxic molecules on the wine LAB cell membrane, whether initially present as must components or synthesized during alcoholic fermentation. Definitive genetic stud- ies to explain these observations, however, were hampered as the required techniques were not yet available. The early 2000s marked a turning point in the study of Oenococcus oeni, as sequencing of the entire genome became possible. The next step was comparing genomes of various strains and then linking them to known physical char- acteristics of the strains. Today there are 23 listed O. oeni ge- nomes in the international sequencing bank at the National Center for Biotechnology Information. Computer data processing has permitted a better understanding of the genetic origin of properties associated with O. oeni strains. The necessity of compiling culture collec- tions representative of geographic regions or wine types (or both) has gradually become apparent. Enology research centers in wine- growing regions worldwide isolate and geno- type malolactic bacteria strains native to certain environmental conditions and conduct selection programs. Genomic applications to select wine lactic acid bacteria starters Winemakers and producers of wine LAB cultures quickly saw the differences between strains of O. oeni—both in their effectiveness at degrading L-malic acid and in their impact on wine sensory attributes. The observation that the same strain does not behave in the same manner in different wines is not sur- prising, as the growth and survival param- e t e r s a r e d i f f e r e n t a m o n g w i n e s . T h e converse is also true. In the same wine, results will differ accord- ing to the strain, which means different strains have distinct properties, and it is important to understand why. The knowledge of genomes should allow us to identify genes, sets of genes and genetic regions—all of which may be re- sponsible for these differences. The construction of exhaustive microbial strain collections allows for statistically signifi- cant data collection and is critical for such work. An example is the Divoeni collection of 560 O. oeni strains isolated throughout the Get your fermentation moving – Introduce selected bacteria! Together with yeast, our selected bacteria are winemaking tools contributing to wine aromas. VP41™ PN4™ BETA™ ALPHA™ O-MEGA™ 31™ www.lallemandwine.com Scott Laboratories: 707 765-6666 – info@scottlab.com – www.scottlab.com Research on the stress response of wine LAB mainly has targeted the pH, alcohol level and overall composition and variability of wine itself.