Macrowine 2021
IVES 9 IVES Conference Series 9 Improvement of non-Saccharomyces yeast dominance during must fermentation by using spontaneous mutants resistant to SO2, EtOH and high pressure of CO2

Improvement of non-Saccharomyces yeast dominance during must fermentation by using spontaneous mutants resistant to SO2, EtOH and high pressure of CO2

Abstract

AIM: A genetic study of four wine T. delbrueckii strains was done. Spore clones free of possible recessive growth‐retarding alleles with enhanced resistance to winemaking stressing conditions were obtained from these yeasts.

METHODS: The genetic marker of resistance to cycloheximide (cyhR) allows easy monitoring of the new mutants obtained from these yeasts. Identity of the high pressure resistant (HPR) mutants was verified by analysis of cell morphology, killer phenotype, cyhR marker, presence of viral dsRNA, RFLPs of mtDNA, and sequencing of Internal Transcribed Spacer ofribosomal DNA (ITS).

RESULTS: T. Delbrueckii mutants were isolated from some spore clones. Papillae resistant to SO2 were isolated. Subsequently, new spontaneous mutants capable of growing on YEPD plates with 10% ethanol were isolated. Rosé sparkling wine (cava) was made using these mutants. Two mutants, with the best fermentation kinetics and closest to the reference yeast Sc 85R4, were isolated from some bottles with high CO2 pressure and some were selected there after (Td MutHP41 and Td MutHP42). They had better fermentation kinetics and dominance than their parental yeast. Td MutHP41 showed great improvement for industrial base wine fermentation with respect to its parental yeast. Re-isolation and selection procedure to obtain new reinforced HPR mutants from previously selected HPR mutants was not a sound strategy to continue improving the fermentative capability of T. delbrueckii under high CO2 pressure. Continuous shaking during inocula preparation further improved the fermentative capability of T. delbrueckii yeasts.

CONCLUSIONS: Isolation of spontaneous mutants resistant to SO2 and ethanol seems to be a good strategy to slightly improve the fermentative efficiency of T. delbrueckii in must and base wine. The new mutants were genetically stable enough to be considered for industrial production, and their fermentative capability was further improved by continuously supplying oxygen during the conditioning stage before yeast culture inoculation in base wine.

DOI:

Publication date: September 10, 2021

Issue: Macrowine 2021

Type: Article

Authors

Alberto Martínez Brígido 1, Rocío Velázquez 1, Joaquín Bautista-Gallego 1, Emiliano Zamora 2, Manuel Ramírez 1

1 Departamento de Ciencias Biomédicas, Universidad de Extremadura, 06006 Badajoz, Spain.
2 Estación Enológica, Junta de Extremadura. 

Contact the author

Keywords

Torulaspora delbrueckii; wine fermentation, sporeclone; sparkling wine; ethanol resistance; SO2 resistance; pressure resistance

Citation

Related articles…

Pedoclimatic comparison of three viticultural areas of Italy devoted to high-quality Aglianico and Cabernet Sauvignon production

Aim: The study aims to show how different pedo-climatic conditions (past, present, and future) in three Italian sites at different latitudes (from center to southern), affect the adaptation of two red grapevine cultivars: Aglianico and Cabernet Sauvignon.

Read More

Toward an automatic way to identify red blotch infected vines from hyperspectral images acquired in the field

Vineyards are affected by different virus diseases, which can lower yield and affect the quality of grapes. Grapevine red blotch disease is one of them, and no curative solution exists. Once infected, a vine must be removed and replaced with a virus-free vine (aka roguing). Screening vineyards to look for symptoms can be time-consuming and needs well-trained experts. To improve this process, we conducted an experiment identifying infected vines using a hyperspectral camera in the field.

Read More

Determination of secondary metabolites as quality and typicalness tracers in autochthonous vitis vinifera grapes and wines from Ischia isle

[lwp_divi_breadcrumbs home_text="IVES" use_before_icon="on" before_icon="||divi||400" module_id="publication-ariane" _builder_version="4.19.4" _module_preset="default" module_text_align="center" module_font_size="16px" text_orientation="center"...
Read More

Lamp – a modern tool for the detection of fungal infections in the vineyard

AIM: Loop-mediated isothermal amplification (LAMP) [1] is a modern technology for fast and sensitive amplification of specific DNA sequences under isothermal conditions. Its simple handling and no need for dedicated equipment together with an evaluation of the amplification event by in-tube detection make this method advantageous and economically affordable for on-site investigations in the industry.

Read More

Impact of the non-volatile matrix composition on red wine aroma release and perception of olfactory and oral cues

Aroma and mouthfeel cues are the main characteristics defining red wine quality. During wine tasting, perceptual and physical-chemical phenomena leading to mutual interactions between volatiles and non-volatiles sensory active compounds, can occur. Aroma perception depends on the release of volatiles from wine, that is affected by wine constituents present in the medium (Pittari et al. 2021; Lyu et al. 2021). Our aim was to evaluate the effect of the non-volatile wine matrix composition (polyphenols, PPh) on the release and perception of red wine aromas by an experiment of matrix enrichment.

Read More