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Novel methods to manipulate autolysis in sparkling wine: effects on yeast


Gnoinski, GB and Schmidt, SA and Close, DC and Goemann, K and Pinfold, TL and Kerslake, FL, Novel methods to manipulate autolysis in sparkling wine: effects on yeast, Molecules, 26, (2) Article 387. ISSN 1420-3049 (2021) [Refereed Article]

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DOI: doi:10.3390/molecules26020387


Sparkling wine made by the traditional method (Méthode Traditionelle) develops a distinct and desirable flavour and aroma profile attributed to proteolytic processes during prolonged ageing on lees. Microwave, ultrasound and addition of β-glucanase enzymes were applied to accelerate the disruption of Saccharomyces cerevisiae, and added to the tirage solution for secondary fermentation in traditional sparkling winemaking. Scanning electron microscopy and flow cytometry analyses were used to observe and describe yeast whole-cell anatomy, and cell integrity and structure via propidium iodide (PI) permeability after 6-, 12- and 18-months post-tirage. Treatments applied produced features on lees that were distinct from that of the untreated control yeast. Whilst control yeast displayed budding cells (growth features) with smooth, cavitated and flat external cell appearances; microwave treated yeast cells exhibited modifications like ‘doughnut’ shapes immediately after treatment (time 0). Similar ‘doughnut’-shaped and ‘pitted/porous’ cell features were observed on progressively older lees from the control. Flow cytometry was used to discriminate yeast populations; features consistent with cell disruption were observed in the microwave, ultrasound and enzyme treatments, as evidenced by up to 4-fold increase in PI signal in the microwave treatment. Forward and side scatter signals reflected changes in size and structure of yeast cells, in all treatments applied. When flow cytometry was interpreted alongside the scanning electron microscopy images, bimodal populations of yeast cells with low and high PI intensities were revealed and distinctive ‘doughnut’-shaped cell features observed in association with the microwave treatment only at tirage, that were not observed until 12 months wine ageing in older lees from the control. This work offers both a rapid approach to visualise alterations to yeast cell surfaces and a better understanding of the mechanisms of yeast lysis. Microwave, ultrasound or β-glucanase enzymes are tools that could potentially initiate the release of yeast cell compounds into wine. Further investigation into the impact of such treatments on the flavour and aroma profiles of the wines through sensory evaluation is warranted.

Item Details

Item Type:Refereed Article
Keywords:sparkling wine production, autolysis, microwave, ultrasound, beta-glucanase enzymes, scanning electron microscopy, flow cytometry
Research Division:Agricultural, Veterinary and Food Sciences
Research Group:Food sciences
Research Field:Beverage chemistry and beverage sensory science
Objective Division:Plant Production and Plant Primary Products
Objective Group:Industrial crops
Objective Field:Wine grapes
UTAS Author:Gnoinski, GB (Mrs Gail Gnoinski)
UTAS Author:Close, DC (Professor Dugald Close)
UTAS Author:Goemann, K (Dr Karsten Goemann)
UTAS Author:Pinfold, TL (Dr Terry Pinfold)
UTAS Author:Kerslake, FL (Dr Fiona Kerslake)
ID Code:142392
Year Published:2021
Deposited By:TIA - Research Institute
Deposited On:2021-01-14
Last Modified:2021-03-11

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