Unravelling the Impact of Grape Washing, SO2, and Multi-Starter Inoculation in Lab-Scale Vinification Trials of Withered Black Grapes

Fermentation

Renato L. Binati¹  Sandra Torriani¹  Giovanna E. Felis²  Eleonora Troiano²  Maurizio Ugliano²  Ilaria Checchia² 

[1] Department of Biotechnology, University of Verona, Strada Le Grazie 15, Ca’ Vignal 2, 37134 Verona (VR), Italy;Department of Biotechnology, University of Verona, Villa Lebrecht, Via della Pieve 70, 37029 San Pietro in Cariano (VR), Italy;

关键词: withered grapes;    grape washing;    heavy metals;    grape microbiota;    mixed starter cultures;    fermentations;   

DOI  :  10.3390/fermentation7010043

来源: DOAJ

【 摘 要 】

Wine quality is strongly affected by chemical composition and microbial population of grape must, which, in turn, are influenced by several post-harvest treatments, including grape withering. Different strategies have been suggested to manage the fermenting must microbiota, as it plays a central role in the outcomes of both spontaneous and guided fermentations. This study aimed at evaluating the impact of grape washing, SO₂ addition, and selected starter culture inoculation on population dynamics, fermentation kinetics, and main oenological parameters in lab-scale trials, focusing on withered grapes usually used for Amarone production. Although grape washing treatment was effective in removing heavy metals and undesirable microorganisms from grape berry surface, inoculation of multi-starter cultures impacted more fermentation rates. Further, both grape washing and starter inoculation procedures had a remarkable impact on wine chemical characteristics, while 30 mg/L SO₂ addition did not significantly affect the fermentation process. In summary, the best strategy in terms of limiting off-flavors and potentially reducing the need for SO₂ addition in wine from withered grapes was the use of yeast starters, particularly mixed cultures composed by selected strains of Metschnikowia spp. and Saccharomyces cerevisiae. Application of a washing step before winemaking showed a potential to improve organoleptic characteristics of wine.

【 授权许可】

Unknown