Search results for "sulfites"
showing 6 items of 16 documents
Technological properties of Oenococcus oeni strains isolated from typical southern Italian wines.
2010
Aims: To isolate indigenous Oenococcus oeni strains suitable as starters for malolactic fermentation (MLF), using a reliable polyphasic approach. Methods and Results: Oenococcus oeni strains were isolated from Nero di Troia wines undergoing spontaneous MLF. Samples were taken at the end of alcoholic fermentation and during MLF. Wine samples were diluted in a sterile physiological solution and plated on MRS and on modified FT80. Identification of O. oeni strains was performed by a polymerase chain reaction (PCR) experiment using strain-specific primers. Strains were further grouped using a multiplex RAPD-PCR analysis. Then, six strains were inoculated in two wine-like media with two differe…
A new chromosomal rearrangement improves the adaptation of wine yeasts to sulfite
2019
Sulfite‐generating compounds are widely used during winemaking as preservatives because of its antimicrobial and antioxidant properties. Thus, wine yeast strains have developed different genetic strategies to increase its sulfite resistance. The most efficient sulfite detoxification mechanism in Saccharomyces cerevisiae uses a plasma membrane protein called Ssu1 to efflux sulfite. In wine yeast strains, two chromosomal translocations (VIIItXVI and XVtXVI) involving the SSU1 promoter region have been shown to upregulate SSU1 expression and, as a result, increase sulfite tolerance. In this study, we have identified a novel chromosomal rearrangement that triggers wine yeast sulfite adaptation.…
Characterization of the Viable but Nonculturable (VBNC) State in Saccharomyces cerevisiae
2013
The Viable But Non Culturable (VBNC) state has been thoroughly studied in bacteria. In contrast, it has received much less attention in other microorganisms. However, it has been suggested that various yeast species occurring in wine may enter in VBNC following sulfite stress.In order to provide conclusive evidences for the existence of a VBNC state in yeast, the ability of Saccharomyces cerevisiae to enter into a VBNC state by applying sulfite stress was investigated. Viable populations were monitored by flow cytometry while culturable populations were followed by plating on culture medium. Twenty-four hours after the application of the stress, the comparison between the culturable populat…
A parallel and sensitive software tool for methylation analysis on multicore platforms.
2015
Abstract Motivation: DNA methylation analysis suffers from very long processing time, as the advent of Next-Generation Sequencers has shifted the bottleneck of genomic studies from the sequencers that obtain the DNA samples to the software that performs the analysis of these samples. The existing software for methylation analysis does not seem to scale efficiently neither with the size of the dataset nor with the length of the reads to be analyzed. As it is expected that the sequencers will provide longer and longer reads in the near future, efficient and scalable methylation software should be developed. Results: We present a new software tool, called HPG-Methyl, which efficiently maps bis…
Sulfites and the Wine Metabolome
2017
International audience; In a context of societal concern about food preservation, the reduction of sulfite input plays a major role in the wine industry. To improve the understanding of the chemistry involved in the SO2 protection, a series of bottle aged Chardonnay wines made from the same must, but with different concentrations of SO2 added at pressing were analyzed by ultrahigh resolution mass spectrometry (FT-ICR-MS) and excitation emission matrix fluorescence (EEMF).Metabolic fingerprints from FT-ICR-MS data could discriminate wines according to the added concentration to the must but they also revealed chemistry-related differences according to the type of stopper, providing a wine me…
Effect of different packaging methods on the free amino acid profiles of the deep-water rose shrimp (Parapenaeus longirostris) during frozen storage
2022
The composition of free amino acids (FAAs) in seafood products contributes to characterizing their flavor, as well as freshness and quality during storage. Deep-water rose shrimps (Parapenaues longirostris, Lucas, 1846) (DWRS) are being increasingly harvested in the Mediterranean Sea, and the captured specimens are quickly frozen onboard fishing trawlers to preserve freshness and post-harvest quality. Here, we quantified the FAA profiles of DWRS packaged using five methods: (1) 100% N2; (2) vacuum; (3) 50% N2 + 50% CO2; (4) commercial anhydrous sodium sulfite; and (5) air (control). All samples were quickly frozen at −35°C and stored for 12 months at −18°C. Arginine (661 mg/100 g), proline …