AIM: From the beginning of the yeast autolysis process, several interesting intracellular and cell wall constituyents are released to the media providing different characteristics to the wine, being this process extensively studied in sparkling wines due to their important contribution to their properties (1-2). Yeast derived products (YDs) try to emulate the natural yeast autolysis compounds release enhancing the organoleptic characteristics of resulting wines (2-3). This study is a comprehensive evaluation of the impact of the addition of different YDs added to base wine on the chemical, physical and sensory characteristics of the resulting sparkling wines. METHODS: Chardonnay base wine was employed to carry out this study. Three experimental YDs were added at 5 and 10 g/hL to the tirage liqueur: a yeast autolysate (YA), a yeast protein extract (PE) and an inactivated dry yeast from Torulaspora delbrueckii, (TD), and two commercial specific inactivated dry yeast: OPTIMUM WHITE® (OW) and PURE-LONGEVITY®(PL). After second fermentation, measurements were carried out after 3, 6, 9 and 18 months of aging on lees. General enological parameters, proteins, polysaccharides (HPLC-DAD-RID), volatile compounds profile (GC-MS), foaming characteristics (Mosalux), and descriptive sensory analyses were carried out. RESULTS: Esters decreased significantly for all the YDs added along the first 9 months unless for the cases of YE and OW. However, from 9 to 18 months of aging, the total amount of esters increased in all the treatments except YE and OW, specially remarkable was the increase for wines treated with TD. Terpenes diminished significantly from 9 to 18 months of aging exceptuating again the treatment TD, in where the presence of these compounds increased. Hence, for the production of sparkling wines with a short aging period it would be recommended the addition of YE or OW, and for long aging, TD. No significant differences of the total amount of volatile compounds were found among the different dosages of derivatives tested. After 9 months of aging, YA and OW accounted the highest foamability, specially for the highest dose. In general, the addition of YDs decreased significantly the time to reach the maximum high (TM) of the foam (HM) in wines aged 9 months. Moreover, the addition of YA and OW gave rise to the sparkling wines with the highest foam stability (HS). Sensory trials showed that the differences between aging periods (9 and 18 months) were higher than differences among YDs treatments. CONCLUSIONS: Several secondary metabolites and foam characteristecs were positively influenced by YDs addition to the wines. This, join to the expectations of aging time for that wine, will be essential to decide which of the YDs is better to use during the production of sparkling wines by traditional method.
Authors: Cristina Ubeda – Nutrition and Bromatology Department, Faculty of Pharmacy, University of Seville, Spain. ,Rubén DEL BARRIO-GALÁN, Agroindustry and Enology Department, Faculty of Agronomic Sciences, University of Chile, Santiago, Chile. Mª Ignacia LAMBERT-ROYO, Agroindustry and Enology Department, Faculty of Agronomic Sciences, University of Chile, Santiago, Chile. Nathalie SIECZKOWSKI, Lallemand SAS, 19 rue des Briquetiers, BP 59, 31 702 Blagnac, France. Joan Miquel CANALS, Biochemistry and Biotechnology Department, Faculty of Enology, University Rovira I Virgili, Tarragona, Spain. Álvaro PEÑA-NEIRA, Agroindustry and Enology Department, Faculty of Agronomic Sciences, University of Chile, Santiago, Chile. Mariona GIL i CORTIELLA, Applied Chemical Sciences Institute, Autonomous University of Chile, Santiago, Chile.
Keywords: sparkling wine, yeast derived products, aging on lees, foam characteristics, sensory properties, secondary metabolites