Inoculation with a selected strain of <i>Metschnikowia pulcherrima</i> as a bioprotective alternative to sulphites for preventing browning of white grape must
Marco Bustamante,
Pol Giménez,
Arnau Just-Borràs,
Ignasi Solé-Clua,
Jordi Gombau,
José M. Heras,
Nathalie Sieczkowski,
Mariona Gil,
Joan M. Canals,
Fernando Zamora
Affiliations
Marco Bustamante
Departament de Bioquímica i Biotecnologia, Facultat d’Enologia de Tarragona, Universitat Rovira i Virgili, C/Marcel.li Domingo 1, 43007 Tarragona
Instituto de Ciencias Aplicadas. Facultad de Ingenieria. Universidad Autónoma de Chile. Sede Santiago, Campus Providencia. Av. Pedro de Valdivia 425, Providencia, Santiago
In this study, the effectiveness of a selected strain of Metschnikowia pulcherrima (MP1) was compared to that of sulphur dioxide for preventing white grape must from browning. Sulphur dioxide was found to drastically reduce oxygen consumption rate, protect hydroxycinnamic acids against oxidation and prevent grape must from browning, even in the presence of laccase. By contrast, supplementation with the selected strain of Metschnikowia pulcherrima (MP1) drastically increased oxygen consumption rate, thus reducing the amount of oxygen available for polyphenol oxidases. In the absence of laccase, this resulted in a decrease in browning and a certain degree of protection of the hydroxycinnamic acids, but in the presence of laccase it was not effective enough. Consequently, the selected strain of Metschnikowia pulcherrima (MP1) can be considered an interesting alternative to sulphur dioxide for preventing browning in white grape must, but only in conditions of healthy grapes.