Differential response of Pichia guilliermondii spoilage isolates to biological and physical-chemical factors prevailing in Patagonian wine fermentations

LOPES, CHRISTIAN; SAEZ JULIETA; SANGORRÍN, M.P

CANADIAN JOURNAL OF MICROBIOLOGY

National Research Council Canada

Año: 2008 vol. 55 p. 801 - 809

0008-4166

Pichia guilliermondii could produce volatile phenols at the initial stages of wine fermentations; however, its response to different wine stress conditions has been poorly studied. In this work, we present an analysis of the response of 23 P. guilliermondii indigenous isolates to physical-chemical wine stress factors as well as to indigenous wine killer yeasts. Principal Coordinates Analysis (PCo A) based on data obtained from response patterns was carried out in order to evaluate the relationships among the isolates. Major differences among the isolates were detected in media plates containing 8% ethanol and in those containing 280 g/L glucose. PCoA evidenced three clusters of isolates with different stress response patterns, indicating a relationship between the tolerance to these compounds and the origin of the isolates. P. guilliermondii isolates were sensitive to the toxins produced by the species Hanseniaspora uvarum, Metschnikowia pulcherrima, P. anomala and P. kluyveri; evidencing a maximum level of sensitivity against P. anomala (91% on average). Those isolates obtained from fermenting must proved to be more resistant to killer yeasts than those obtained from grape surfaces. The combined evaluation of the response to physical-chemical and biological factors presented in this work could be a useful standard protocol for the evaluation of the potential spoilage capacity of yeasts in winemaking.