Autochthonous fermentation starters for the industrial production of Negroamaro wines

Abstract

The aim of the present study was to establish a new procedure for the oenological selection of Saccharomyces cerevisiae strains isolated from natural must fermentations of an important Italian grape cultivar, denoted as "Negroamaro". For this purpose, 108 S. cerevisiae strains were selected as they did not produce H(2)S and then assayed by microfermentation tests. The adopted procedure made it possible to identify 10 strains that were low producers of acetic acid and hydrogen sulphide and showed that they completed sugar consumption during fermentation. These strains were characterized for their specific oenological and technological properties and, two of them, strains 6993 and 6920, are good candidates as industrial starter cultures. A novel protocol was set up for their biomass production and they were employed for industrial-scale fermentation in two industrial cellars. The two strains successfully dominated the fermentation process and contributed to increasing the wines' organoleptic quality. The proposed procedure could be very effective for selecting "company-specific" yeast strains, ideal for the production of typical regional wines. "Winery" starter cultures could be produced on request in a small plant just before or during the vintage season and distributed as a fresh liquid concentrate culture.

Improving industrial yeast strains: exploiting natural and artificial diversity

“…Indeed, continuous evolution and adaptation of indigenous yeast strains to their environment have equipped these strains with phenotypes valuable for industry. For example, several research papers have described the isolation, selection, and incorporation of indigenous wine yeasts as starter cultures in the production of wine (Zagorc et al ., 2001; Mannazzu et al ., 2002; Lopes et al ., 2007; Tosi et al ., 2009; Capece et al ., 2010; de Ullivarri et al ., 2011; Scacco et al ., 2012; Tristezza et al ., 2012). Similarly, the application of indigenous yeast strains revolutionized the biofuel industry, where the initially used baker's strains were replaced by ‘contaminating’ strains, which were well adapted to the harsh fermentation environment (Basso et al ., 1993, 2008; da Silva-Filho et al ., 2005).…”

Detailed Analysis of the Microbial Population in Malaysian Spontaneous Cocoa Pulp Fermentations Reveals a Core and Variable Microbiota

“…Therefore, the use of a large-scale culture-dependent approach combined with accurate identification methods such as ribosomal DNA (rDNA) sequencing or DNA fingerprinting [e.g. repetitive DNA sequence-based PCR (rep-PCR), or amplification fragment length polymorphism (AFLP)] will yield both a detailed mapping of the (diversity in the) microbial population and allow isolation of pure cultures that can (after characterization) potentially be applied as starter cultures [21].…”

The vintage effect overcomes the terroir effect: a three year survey on the wine yeast biodiversity in Franciacorta and Oltrepò Pavese, two northern Italian vine-growing areas

“…This assumption is at the base of the Appellation of Origin systems around the globe, with a strong impact on the wine market since they drive consumer choices. Many research groups have explored the opportunity to isolate, select and use indigenous strains with technological properties and quality traits as a strategic asset for wine-makers to unequivocally link a wine with its environment of production (Furdíkova et al, 2014;Martínez et al, 2004;Rodríguez-Palero et al, 2013;Settanni et al, 2012;Tosi et al, 2009;Tristezza et al, 2012). This experimental activity might also be interesting for the manufacturers of starter cultures, because it is the basis for genetic improvement and formulation of new products (Giudici et al, 2005;Mannazzu et al, 2002).…”