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Spanish sparkling wine or cava (Certified Brand of Origin) elaborated following the “champenoise” method undergoes a second fermentation in closed bottles of base wine, followed by aging of wines with lees of at least 9 months. Both processes are considered as important factors contributing to the quality of cava. During the second fermentation, yeasts are subjected to pressure in which the response of the yeast cells have not been still clearly elucidated. The objective of this study is to identify proteins that may participate in the response to pressure. OFFGEL fractionator coupled to LTQ Orbitrap XL MS equipment were used trying to detect the maximum possible number of proteins in yeasts grown in a traditional second fermentation condition and under a reference condition not subjected to pressure. The obtained proteomic profiles show 679 proteins detected under the first condition while 979 under the reference condition. From the total number of proteins identified under the second fermentation with pressure, 251 were just detected under it being mainly ribosomal and extracellular; and involved in biological processes such as ribosome assembly, cytoplasmic translation or organelle assembly. The cellular components and biological processes mentioned in this study may be essential for the fermenting yeast survival in a condition such as second fermentation during sparkling wine elaboration. Genetic experiments are needed to definitively confirm the necessity of these proteins synthesis under pressure.

The training of human resources improves business performance: myth or reality? While the literature has extensively addressed this issue, the transfer that occurs from training to performance still remains unresolved. The present study suggests an empirical solution to this gap, through a multiple mediation model of dynamic capabilities. Accordingly, the study makes a major contribution to the effectiveness of an organizational-level training: the "true" relationship between training and performance is mediated by absorptive and innovative capacities. It is difficult from training to directly affect the results: it must be done through a chain of intermediate variables. Training can be argued to be indirectly related to performance, through absorptive capacity in the first place, and innovative capacity in the second, sequentially in this order (three-path mediated effect). Of all immediate relationships received by performance, its explained variance is achieved partly via absorptive capacity and partly via innovation. The direct relationship through training is not significant and only explains a small percentage of the variance in performance. These results have been corroborated by combining two methods of analysis: PLS-SEM and fsQCA, using data from an online survey. This dual methodology in the study of the same phenomenon allows overcoming the limitations of each method, which would not have been possible with a single methodological approach, and confirming the findings obtained by any of them.

The most important dogma in white-wine production is the preservation of the wine aroma and the limitation of the oxidative action of oxygen. In contrast, the aging of Sherry and Sherry-like wines is an aerobic process that depends on the oxidative activity of flor strains of Saccharomyces cerevisiae. Under depletion of nitrogen and fermentable carbon sources, these yeast produce aggregates of floating cells and form an air-liquid biofilm on the wine surface, which is also known as velum or flor. This behavior is due to genetic and metabolic peculiarities that differentiate flor yeast from other wine yeast. This review will focus first on the most updated data obtained through the analysis of flor yeast with -omic tools. Comparative genomics, proteomics, and metabolomics of flor and wine yeast strains are shedding new light on several features of these special yeast, and in particular, they have revealed the extent of proteome remodeling imposed by the biofilm life-style. Finally, new insights in terms of promotion and inhibition of biofilm formation through small molecules, amino acids, and di/tri-peptides, and novel possibilities for the exploitation of biofilm immobilization within a fungal hyphae framework, will be discussed.