IJWR-4567-Identification of Dominant Species of Lactic Acid Bact_060509

© 2009 Saguir et al, publish er and licensee Dove Medical Press Ltd. This is an Open Access article which permits unrestricted noncommercial use, pro vided the original work is properly cited. International Journal of Wine Research 2009:1 175–185 International Journal of Wine Research 175 ORIGINAL RESEARCH Dovepress open access to scientifc and medical research Open Access Full Text Article submit your manuscript | www.dovepress.com Dovepress Identication of dominant lactic acid bacteria isolated from grape juices. Assessment of its biochemical activities relevant to avor dev elopment in wine Fabiana Maria Saguir 1,3 Iris Eleonora Loto Campos 1 Carmen Maturano 1 Maria Cristina Manca de Nadra 1,2,3 1 Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán, Tucumán, Argentina; 2 Centro de Referencia para Lactobacilos (Cerela), Tucumán, Argentina; 3 Career Investigators from Consejo Nacional de Investigaciones Cientícas y Técnicas, Argentina Correspondence: Fabiana Maria Saguir Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán, Ayacuc ho 491, 4000 Tucumán, Argentina T el +54 381 425 1425 Fax +54 381 431 172/400 5600 Email [email protected] Abstract: We investigated the dominant lactic acid bacteria (LAB) rom grape juice and commencement o malolactic ermentation (MLF) samples o a cellar located in Argentina and assessment o its β-glucosidase activity and butter aroma compounds production. LAB number ound in grape juice (approximately log 10 3.3) was lower than that obtained in the MLF samples. Oenococcus oeni was predominant, accounting or 68% o the 81 LAB isolated. Majority o whole cells derived rom O. oeni cultures at the end o the exponential growth showed detect- able β-glucosidase activity. Contraril y, the highest proportion o them did not produce diacetyl, acetoin, and 2,3-butylene glycol. A direct relation between both properties among the O. oeni strains could not be established. In the selected MS25 strain, l-malic acid was compatible with good enzyme activity and was partially able to annul the negative inuence o the low pH (3.8). In dierent conditions, the aroma compounds were lower than 4 mg/ml, especially at pH 3.8 and in presence o l-malic acid (2.5 g/l). This strain could have adequate characteristics or potential use in winemaking. Finally, the assessment o both biochemica l properties in O. oeni should be considered as a quality criterion or selecting starter cultures or the improvement o the wines aroma. Keywords: isolation, lactic acid bacteria, biochemical properties, aroma, wine Introduction Lactic acid bacteria (LAB) are widely used in ood biotechnology and efcient control o these microbiological processes requires an increase in our knowledge about their ecology and biochemical activities. LAB occur naturally on grapes and their ability to grow in wine had been documented. 1,2 LAB associated with the wine making process belongs to the genera Lactobacillus, Leuconostoc, Oenococcus , and Pediococcus. 3–5 Malolactic ermentation (MLF) induced by LAB, ater alcoholic ermentation (AF), is a suitable process or correct wine acidity. It consist s o the l-malic acid decarboxylation to lactic acid, resulting in a wine with a soter mouth eel. At the same time, the MLF provides stabi lity or wines to be aged and the ad dition o avors b y modiying ruit- derived aromas and producing aroma-active compounds. 1,6 One o the most evident avor changes is the development o a ‘buttery’ or ‘butterscotch’ character. Diacetyl has been attributed to being a major contributor to this buttery character in wine. 7,8 This metabolite can be ormed rom citric acid in wine. Saguir and Manca de Nadra 9 demonstrated that l-malic and citric acids avored wine Oenococcus oeni strain growth in nutritional stress conditions and that, Number of times this article has been viewed This article was published in the following Dove Press journal: International Journal of Wine Research 5 June 2009

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IJWR-4567-Identification of Dominant Species of Lactic Acid Bact_060509