Release of Nucleotides and Nucleosides during Yeast Autolysis:  Kinetics and Potential Impact on Flavor

Abstract

Nucleotides, particularly 5'-nucleotides, are important flavoring agents found in many foods and beverages. Their precise effect on the flavor of wines aged on lees has not been examined previously. In this study nucleotides and nucleosides released by yeast during autolysis in a model wine system and in Champagne wines were identified and quantified, and their impact on wine flavor was determined. Ribonucleotides only were detected in yeast autolysate and in Champagne wines. In wines ribonucleotides were quantified by tandem mass spectrometry coupled to HPLC. The maximum concentration of total nucleotides was very low with a maximum of approximately 3 mg/L in wine aged on yeasts for 9 years. In young wines the most important nucleotide was 5'-UMP, but after 2 years of aging its concentration decreased and the concentration of 5'-GMP slowly increased. The threshold values of the most representative nucleotides in Champagne wines were higher than the concentrations found in the same wines. However, it is known that there is synergism between the different nucleotides and also in the presence of glutamic acid. This phenomenon could explain the difference observed in descriptive profiles of wines spiked with nucleotides.

Biotechnologies in sparkling wine production. Interesting approaches for quality improvement: A review

“…Zhao and Fleet (2005) reported that RNA degradation plays a key role in yeast autolysis, this reaction leads to the release of 3 0 -, 5 0 -and 2 0 -ribonucleotides. Recently, Charpentier et al (2005), have recognised 5 0 -UMP, 5 0 -GMP and 5 0 -IMP in Champagne aged over lees. Even if these compounds are well recognised as flavour compounds, further studies are required to establish their impact on the sensorial properties of sparkling wines .…”

A FTIR microspectroscopy study of autolysis in cells of the wine yeast Saccharomyces cerevisiae

“…It is characterized by the loss of membrane functionality and by the enzymatic degradation of nucleic acids, proteins, lipids and polysaccharides [16,17]. Most researches carried out on autolysis in oenology aimed at analyzing the products released into the medium [18][19][20][21], although morphological changes during autolysis have been studied in cells at the ultra structural level using microscopy techniques [22]. Moreover, in these studies only the determination of a single family of compounds was achieved using time consuming conventional chemical and biochemical techniques such as gas chromatography and high-performance liquid chromatography.…”

“…To this aim, we induced autolysis in cells of Saccharomyces cerevisiae EC1118, a commercial wine yeast previously well characterized for its autolytic behaviour [18,19,21,22], both in a model wine medium and in a base wine. Measurements were carried out on yeast cells before and after 5 days of induced autolysis, when all major biochemical events are completed [18][19][20][21].…”

Impact of yeast and bacteria on beer appearance and flavour

“…Limited evidence suggests that nucleotides could have an effect on wine taste (Charpentier et al, 2005). glutamic acid, Glu), nucleotides (e.g.…”