Macrowine 2021
IVES 9 IVES Conference Series 9 Aroma profile of Oenococcus oeni strains in different life styles

Aroma profile of Oenococcus oeni strains in different life styles

Abstract

AIM: Three Oenococcus oeni strains previously isolated from spontaneous malolactic fermentation were characterized for their surface properties. Planktonic and sessile cells were investigated for aroma compounds production and the expression of genes involved in citrate and malate metabolism (citE and mleA, respectively), glycoside-hydrolase (dsrO), fructansucrase (levO), rhamnosyl-transferase (wobB), glycosyltransferase (wobO).

METHODS: Bacterial adhesion on polystyrene was evaluated using 96-well plates in MRS and must. Planktonic and sessile cells were numbered by plate count. Biofilm formation was also visualized by confocal laser scanning microscopy (CLSM, Nikon A1R) using hoechst fluorescent dye. Aroma compounds produced by sessile and planktonic cells were determined by solid phase microextraction coupled with gas chromatography (GC/MS SPME). RNA was extracted using using the Tri-reagent method (Sigma-Aldrich) according to the manufacturer’s instructions. Real-time analysis was performed using an iCycler IQ realtime PCR Detection System (Bio-Rad). ldhD and gyrA were used as reference genes. Fold changes were determined using the 2-ΔΔCT method.

RESULTS: The strains adhered to polystyrene in presence of MRS and must. In any case all strains preferred the planktonic state. CSLM was used to visualize cells distribution and their aggregation and confirmed that strains were able to form biofilm in must and MRS in a strain specific way. Quantitative and qualitative differences on aromatic compounds production were also detected. Higher alcohols and esters were mainly produced in the planktonic state, while organic acids in the sessile one. A strain specific behaviour was observed also for gene expression.

CONCLUSIONS: Biofilm formation can modulate aroma compounds production and probably the organoleptic characteristics of wine. Gene expression analysis revealed that aggregation state can influence malate and citrate metabolism. Further investigations are necessary to evaluate the interaction between Saccharomyces cerevisiae/non-Saccharomyces strains and O. oeni in biofilm formation in order to modulate wine characteristics.

DOI:

Publication date: September 3, 2021

Issue: Macrowine 2021

Type: Article

Authors

Rosanna Tofalo, Giorgia PERPETUINI,  Alessio Pio  ROSSETTI, Carlo PERLA

Faculty of Bioscience and Technology for Food, Agriculture and Environment, University of Teramo, Via R. Balzarini 1, 64100 Teramo, (TE), Italy, Faculty of Bioscience and Technology for Food, Agriculture and Environment, University of Teramo, Via R. Balzarini 1, 64100 Teramo, (TE), Italy Noemi BATTISTELLI, Faculty of Bioscience and Technology for Food, Agriculture and Environment, University of Teramo, Via R. Balzarini 1, 64100 Teramo, (TE), Italy  Luca VALBONETTI,  Faculty of Bioscience and Technology for Food, Agriculture and Environment, University of TeramoVia R. Balzarini 1, 64100 Teramo, (TE), Italy,  Faculty of Bioscience and Technology for Food, Agriculture and Environment, University of Teramo, Via R. Balzarini 1, 64100 Teramo, (TE), Italy Giuseppe ARFELLI,  Faculty of Bioscience and Technology for Food, Agriculture and Environment, University of Teramo, Via R. Balzarini 1, 64100 Teramo, (TE), Italy , Dalton Biotecnologie S.R.L., Spoltore, PE, Italy Rosanna TOFALO Faculty of Bioscience and Technology for Food, Agriculture and Environment, University of Teramo, Via R. Balzarini 1, 64100 Teramo, (TE), Italy

Contact the author

Keywords

oenococcus oeni, gene expression, aroma profile, biofilm

Citation

Related articles…

Influence Of Phytosterols And Ergosterol On Wine Alcoholic Fermentation For Saccharomyces Cerevisiae Strains

Sterols are a fraction of the eukaryotic lipidome that is essential for the maintenance of the cell membrane integrity and their good functionality. During alcoholic fermentation, they ensure yeast growth, metabolism and viability, as well as resistance to osmotic stress and ethanol inhibition. Two sterol sources can support yeasts to adapt to fermentation stress conditions: ergosterol, produced by yeast in aerobic conditions, and phytosterols, plant sterols found in grape musts imported by yeasts in anaerobiosis. Little is known about the physiological impact of the assimilation of phytosterols in comparison to ergosterol and the influence of sterol type on fermentation kinetics parameters.

An overview of the impact of clone, environmental factors and viticultural techniques on rotundone concentration in red wines

Rotundone is the main aroma compound responsible for peppery notes in red wine. This positive and very potent molecule has an odor threshold of 8 ng/L in water and 16 ng/L in red wine. It has been detected in several grape varieties with some of the highest concentrations recorded in Syrah, Duras, Tardif and Noiret, an interspecific hybrid grown in the North-East of the USA. If several winemaking practices have been identified to lower rotundone in wine, up to date, no enological solution has proved its efficiency to maximize it. This means that efforts to produce high rotundone wines must be undertaken in vineyards. This work provides practical ways that can be used by winegrowers to modulate rotundone levels in their wines.

The Soil Component of Terroir

Evidence for a specific effect of soil mineral composition on wine character is largely anecdotal. However, soil potassium supply to the vine must be properly balanced between deficiency and excess for good fruit quality.

Shading grapevines with dynamic agrivoltaics address the challenge of early ripening and wine quality related with climate change

Context and purpose of the study. Climate change accelerates grapevine’s phenology, advancing harvests by 2–3 weeks over the past 40 years negatively affecting wine style due to a lack of acidity and too much alcohol.

Waste valorization in winery and distillery industry by producing biofertilizers and organic amendments

The winery and distilling spirits industry generate a remarkable amount of by-products and wasted, that are not properly managed, posing socioeconomic problems and environmental risks, due to its seasonal and polluting characteristics.