Application of Supercritical CO2 Extraction for the Elimination of Odorant Volatile Compounds from Winemaking Inactive Dry Yeast Preparation

7 páginas, 4 figuras, 4 tablas.A procedure based on the application of supercritical CO2 extraction to reduce and/or to remove odorant volatile compounds from a winemaking inactive dry yeast (IDY) preparation has been set up. By applying a factorial design, a screening of different temperatures and pressure conditions was assayed in order to determine the optimal deodorization conditions, and afterward the effect of several sample pretreatments was investigated. The best extraction conditions were achieved at 200 atm and 60 °C, applying the cryogenic grinding of the sample and using 40% (w/w) ethanol as cosolvent. By using these conditions, it was possible to reduce to approximately 70% of the volatile compounds present in the samples that may be released into the wines and therefore affecting their sensory characteristics. Odorant volatile compounds such as 2-methylhydroxypyrrole, 2-ethyl-6-methylpyrazine, and 2,3,5-trimethylpyrazine completely disappeared from the deodorized sample as verified by GC-O analysis. Additional experiments in model wines confirmed the low release of volatile compounds from the deodorized samples, without provoking any change to their nonvolatile composition (nitrogen compounds and neutral polysaccharides) that is related to the technological properties of these preparations.M.A.P.-B. and I.A.-O. thank the MICIN and CAM for their respective Ram on y Cajal (RYC- 2009-05370) and predoctoral contracts and the Spanish Ministerio de Ciencia e Innovaci on for funding of projects (PET2007_0134 and Consolider-Ingenio CSD2007-00063).Peer reviewe

Application of Supercritical CO2 Extraction for the Elimination of Odorant Volatile Compounds from Winemaking Inactive Dry Yeast Preparation

7 páginas, 4 figuras, 4 tablas.A procedure based on the application of supercritical CO2 extraction to reduce and/or to remove odorant volatile compounds from a winemaking inactive dry yeast (IDY) preparation has been set up. By applying a factorial design, a screening of different temperatures and pressure conditions was assayed in order to determine the optimal deodorization conditions, and afterward the effect of several sample pretreatments was investigated. The best extraction conditions were achieved at 200 atm and 60 °C, applying the cryogenic grinding of the sample and using 40% (w/w) ethanol as cosolvent. By using these conditions, it was possible to reduce to approximately 70% of the volatile compounds present in the samples that may be released into the wines and therefore affecting their sensory characteristics. Odorant volatile compounds such as 2-methylhydroxypyrrole, 2-ethyl-6-methylpyrazine, and 2,3,5-trimethylpyrazine completely disappeared from the deodorized sample as verified by GC-O analysis. Additional experiments in model wines confirmed the low release of volatile compounds from the deodorized samples, without provoking any change to their nonvolatile composition (nitrogen compounds and neutral polysaccharides) that is related to the technological properties of these preparations.M.A.P.-B. and I.A.-O. thank the MICIN and CAM for their respective Ram on y Cajal (RYC- 2009-05370) and predoctoral contracts and the Spanish Ministerio de Ciencia e Innovaci on for funding of projects (PET2007_0134 and Consolider-Ingenio CSD2007-00063).Peer reviewe