AUTHOR=Aponte Maria , Blaiotta Giuseppe 

TITLE=Potential Role of Yeast Strains Isolated from Grapes in the Production of Taurasi DOCG

JOURNAL=Frontiers in Microbiology

VOLUME=7

YEAR=2016

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2016.00809

DOI=10.3389/fmicb.2016.00809

ISSN=1664-302X

ABSTRACT=<p>Twelve samples of Aglianico grapes, collected in different locations of the Taurasi DOCG (Appellation of Controlled and Guaranteed Origin) production area were naturally fermented in sterile containers at room temperature. A total of 70 yeast cultures were isolated from countable WL agar plates: 52 in the middle of the fermentation and 18 at the end. On the basis of ITS-RFLP analysis and ITS sequencing, all cultures collected at the end of fermentations were identified as <italic>Saccharomyces (S.) cerevisiae</italic>; while, the 52 isolates, collected after 1 week, could be referred to the following species: <italic>Metschnikowia</italic> (<italic>M</italic>.) <italic>pulcherrima</italic>; <italic>Starmerella</italic> (<italic>Star</italic>.) <italic>bacillaris</italic>; <italic>Pichia</italic> (<italic>P</italic>.) <italic>kudriavzevii</italic>; <italic>Lachancea</italic> (<italic>L</italic>.) <italic>thermotolerans</italic>; <italic>Hanseniaspora (H.) uvarum</italic>; <italic>Pseudozyma (Pseud.) aphidis</italic>; <italic>S. cerevisiae</italic>. By means of Interdelta analysis, 18 different biotypes of <italic>S. cerevisiae</italic> were retrieved. All strains were characterized for ethanol production, SO<sub>2</sub> resistance, H<sub>2</sub>S development, β-glucosidasic, esterasic and antagonistic activities. Fermentation abilities of selected strains were evaluated in micro-fermentations on Aglianico must. Within non-<italic>Saccharomyces</italic> species, some cultures showed features of technological interest. Antagonistic activity was expressed by some strains of <italic>M. pulcherrima, L. thermotolerans, P. kudriavzevii</italic>, and <italic>S. cerevisiae</italic>. Strains of <italic>M. pulcherrima</italic> showed the highest β-glucosidase activity and proved to be able to produce high concentrations of succinic acid. <italic>L. thermotolerans</italic> produced both succinic and lactic acids. The lowest amount of acetic acid was produced by <italic>M. pulcherrima</italic> and <italic>L. thermotolerans;</italic> while the highest content was recorded for <italic>H. uvarum</italic>. The strain of <italic>Star. bacillaris</italic> produced the highest amount of glycerol and was able to metabolize all fructose and malic acid. Strains of <italic>M. pulcherrima</italic> and <italic>H. uvarum</italic> showed a low fermentation power (about 4%), while, <italic>L. thermotolerans, Star. Bacillaris</italic>, and <italic>P. kudriavzevii</italic> of about 10%. Significant differences were even detected for <italic>S. cerevisiae</italic> biotypes with respect to H<sub>2</sub>S production, antagonistic activity and β-glucosidase activity as well as for the production of acetic acid, glycerol and ethanol in micro-vinification experiments.</p>