caa a22 4500 605499837 CHVBK 20210128100553.0 cr unu---uuuuu 210128e20150501xx s 000 0 eng 10.1007/s00253-014-6321-3 doi (NATIONALLICENCE)springer-10.1007/s00253-014-6321-3 The impact of oxygen on the final alcohol content of wine fermented by a mixed starter culture [Elektronische Daten] [Pilar Morales, Virginia Rojas, Manuel Quirós, Ramon Gonzalez] We have developed a wine fermentation procedure that takes advantage of the metabolic features of a previously characterized Metschnikowia pulcherrima strain in order to reduce ethanol production. It involves the use of M. pulcherrima/Saccharomyces cerevisiae mixed cultures, controlled oxygenation conditions during the first 48h of fermentation, and anaerobic conditions thereafter. The influence of different oxygenation regimes and initial inoculum composition on yeast physiology and final ethanol content was studied. The impact of oxygenation on yeast physiology goes beyond the first aerated step and influences yields and survival rates during the anaerobic stage. The activity of M. pulcherrima in mixed oxygenated cultures resulted in a clear reduction in ethanol yield, as compared to S. cerevisiae. Despite relatively low initial cell numbers, S. cerevisiae always predominated in mixed cultures by the end of the fermentation process. Strain replacement was faster under low oxygenation levels. M. pulcherrima confers an additional advantage in terms of dissolved oxygen, which drops to zero after a few hours of culture, even under highly aerated conditions, and this holds true for mixed cultures. Alcohol reduction values about 3.7% (v/v) were obtained for mixed cultures under high aeration, but they were associated to unacceptable volatile acidity levels. In contrast, under optimized conditions, only 0.35g/L acetic acid was produced, for an alcohol reduction of 2.2% (v/v), and almost null dissolved oxygen during the process. The Author(s), 2015 Low alcohol nationallicence Non- Saccharomyces yeast nationallicence Respiratory quotient nationallicence Dissolved oxygen nationallicence Volatile acidity nationallicence Morales Pilar Instituto de Ciencias de la Vid y del Vino (CSIC, Universidad de la Rioja, Gobierno de La Rioja), Logroño, La Rioja, Spain aut Rojas Virginia Instituto de Ciencias de la Vid y del Vino (CSIC, Universidad de la Rioja, Gobierno de La Rioja), Logroño, La Rioja, Spain aut Quirós Manuel Instituto de Ciencias de la Vid y del Vino (CSIC, Universidad de la Rioja, Gobierno de La Rioja), Logroño, La Rioja, Spain aut Gonzalez Ramon Instituto de Ciencias de la Vid y del Vino (CSIC, Universidad de la Rioja, Gobierno de La Rioja), Logroño, La Rioja, Spain aut Applied Microbiology and Biotechnology Springer Berlin Heidelberg 99/9(2015-05-01), 3993-4003 0175-7598 99:9<3993 2015 99 253 https://doi.org/10.1007/s00253-014-6321-3 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s00253-014-6321-3 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Morales Pilar Instituto de Ciencias de la Vid y del Vino (CSIC, Universidad de la Rioja, Gobierno de La Rioja), Logroño, La Rioja, Spain aut NATIONALLICENCE 700 1- Rojas Virginia Instituto de Ciencias de la Vid y del Vino (CSIC, Universidad de la Rioja, Gobierno de La Rioja), Logroño, La Rioja, Spain aut NATIONALLICENCE 700 1- Quirós Manuel Instituto de Ciencias de la Vid y del Vino (CSIC, Universidad de la Rioja, Gobierno de La Rioja), Logroño, La Rioja, Spain aut NATIONALLICENCE 700 1- Gonzalez Ramon Instituto de Ciencias de la Vid y del Vino (CSIC, Universidad de la Rioja, Gobierno de La Rioja), Logroño, La Rioja, Spain aut NATIONALLICENCE 773 0- Applied Microbiology and Biotechnology Springer Berlin Heidelberg 99/9(2015-05-01), 3993-4003 0175-7598 99:9<3993 2015 99 253