Torulaspora delbrueckii Phenotypic and Metabolic Profiling towards Its Biotechnological Exploitation

Abstract

Wine is a particularly complex beverage resulting from the combination of several factors, with yeasts being highlighted due to their fundamental role in its development. For many years, non-Saccharomyces yeasts were believed to be sources of spoilage and contamination, but this idea was challenged, and many of these yeasts are starting to be explored for their beneficial input to wine character. Among this group, Torulaspora delbrueckii is gaining relevance within the wine industry, owing to its low volatile acidity production, increased release of aromatic compounds and enhanced color intensity. In addition, this yeast was also attracting interest in other biotechnological areas, such as bread and beer fermentation. In this work, a set of 40 T. delbrueckii strains, of varied geographical and technological origins, was gathered in order to characterize the phenotypic behavior of this species, focusing on different parameters of biotechnological interest. The fermentative performance of the strains was also evaluated through individual fermentations in synthetic grape must with the isolates’ metabolic profile being assessed by HPLC. Data analysis revealed that T. delbrueckii growth is significantly affected by high temperature (37 °C) and ethanol concentrations (up to 18%), alongside 1.5 mM SO2, showing variable fermentative power and yields. Our computation models suggest that the technological origin of the strains seems to prevail over the geographical origin as regards the influence on yeast properties. The inter-strain variability and profile of the products through the fermentative processes reinforce the potential of T. delbrueckii from a biotechnological point of view.

Molecular and Physiological Diversity of Indigenous Yeasts Isolated from Spontaneously Fermented Wine Wort from Ilfov County, Romania

“…Although the M5 isolate could not be associated with any species using automated systems, its biochemical profile was compared to that of different yeast species that are frequently encountered in wine fermentation. Among them, the T. delbrueckii species proved to be the most suitable since it is characterized by a special metabolic versatility and is strongly influenced by the isolation source of the tested isolates [ 20 , 42 ].…”

“…In the same study, it is presented that some P. kudriavzevii isolates (2 out of 7) or T. delbrueckii isolates (1 out of 12) can tolerate high concentrations of NaCl (up to 1500 mM). Regarding the ability of T. delbrueckii isolates to tolerate saline stress conditions, some papers suggest that this is more of a strain-dependent feature [ 42 , 60 ]. From this point of view, the T. delbrueckii CMGB-M5 shows good potential for industrial use.…”

Predictability of the community-function landscape in wine yeast ecosystems

“…Several previous works have explored in detail the intra-specific phenotypic diversity of some relevant wine yeasts, such as S. cerevisiae (Camarasa et al, 2011), L. thermotolerans (Hranilovic et al, 2018) or T. delbrueckii (Silva-Sousa et al, 2022). Here, looking at the inter-species diversity, we provide information about ecologically and enologically-relevant traits of 60 wine strains belonging to 30 different yeast species.…”

Contributions of Adaptive Laboratory Evolution towards the Enhancement of the Biotechnological Potential of Non-Conventional Yeast Species

“…Recently, Drumonde-Neves et al [ 9 ] reviewed 80 years of literature about wine yeasts, concluding that 293 different yeast species are associated with winemaking, in addition to the traditional S. cerevisiae . For example, Torulaspora delbrueckii stands out today as one of the most interesting so-called non- Saccharomyces yeast species, bringing a wide array of beneficial flavor and aromatic characteristics to wine [ 10 , 11 ]. The ease with which genes can be manipulated also makes yeast diversity attractive as a biological resource to transfer specific metabolic pathways to S. cerevisiae and establish reliable models to predict phenotype–genotype interactions [ 12 , 13 ].…”

“…During the evolutionary process, aliquots of the evolving populations are usually stocked in glycerol (within 10% to 40%, v/v ) and maintained at −80 °C for further phenotypic analysis [ 35 , 36 , 37 ]. The primary advantages are that this strategy is very easy to set up and use, requires low-cost equipment, can usually be executed by a single operator, and can be adapted to massive parallel cultures [ 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 ], as summarized in Table 1 . However, batch cultures are more susceptible to random drift due to certain shortfalls, which include variations in the population density, growth rates, and different nutrient supplementations, together with fluctuations in environmental conditions [ 29 ].…”