• Login
    View Item 
    •   Home
    • Brock Theses
    • Doctoral Theses
    • Ph.D. Biotechnology
    • View Item
    •   Home
    • Brock Theses
    • Doctoral Theses
    • Ph.D. Biotechnology
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    Browse

    All of BrockUCommunitiesPublication DateAuthorsTitlesSubjectsThis CollectionPublication DateAuthorsTitlesSubjectsProfilesView

    My Account

    LoginRegister

    Statistics

    Display statistics

    Considerations for the Development and Optimization of Wine made from Partially Dehydrated Grapes in Ontario, Canada

    • CSV
    • RefMan
    • EndNote
    • BibTex
    • RefWorks
    Thumbnail
    Name:
    Brock_Kelly_Jennifer_2019
    Size:
    11.24Mb
    Format:
    PDF
    Download
    Author
    Kelly, Jennifer
    Keyword
    winemaking
    yeast
    sensory science
    partially dehydrated grapes
    Ontario wine
    
    Metadata
    Show full item record
    URI
    http://hdl.handle.net/10464/14396
    Abstract
    The appassimento process for making wine can mitigate climatic challenges associated with cool climate winemaking, as fruit is dried post-harvest, reducing vintage-to-vintage variation due to varying fruit quality. Resultant wines fermented from dried grapes are high in ethanol and described as rich and intensely flavoured. One of the quality challenges facing wine made from partially dehydrated grapes is elevated levels of undesirable oxidation compounds, such as ethyl acetate, acetic acid and acetaldehyde. In this study we aim to characterize wines made from a local yeast isolate, Saccharomyces bayanus CN1, which demonstrates limited osmotolerance and may have application to this wine style, as it is a lower producer of such compounds. Wines made with the yeast of interest were compared to wines made with the accepted commercial yeast, Saccharomyces cerevisiae, EC1118. Fermentations were established over two vintages at one and three target starting sugar concentrations and a control, respectively. Wines were chemically (enzymatic) and sensorially analyzed. Wines (year two) were subject to volatile organic compound (VOC) and volatile fatty acid (VFA) measurements via Gas Chromatography-Mass Spectrometry. Another consideration for the development of this wine style is the inclusion of Botrytis cinerea, a pathogenic fungus that commonly develops during grape drying, and may impart favourable sensorial characteristics. Grapes were dried to 28.0°Brix and were fermented with EC1118 at 0 and 10% B. cinerea infection. A consumer preference test (n=153) that measured liking of wines (CN1 and 0% and10% B. cinerea infection) was conducted. Results indicate that CN1’s upper limit for fermentation to dryness is 27.5°Brix. All CN1 wines had significantly lower concentrations (p<0.05) of oxidation compounds than the commercial yeast, and oppositely, higher glycerol levels, along with comparable ethanol concentration to EC1118 wines. Significant differences in the concentrations of VOCs and VFAs, such as 2-phenylethanol and hexanoic acid were observed both within °Brix treatments and amongst yeast strains. Sensorially, the wines differed in intensity for a number of attributes. The consumer study revealed no preference between wines vinified with the different yeast strains. This work will contribute to the optimization of this wine style in cool climate winemaking regions and beyond.
    Collections
    Ph.D. Biotechnology

    entitlement

     
    DSpace software (copyright © 2002 - 2022)  DuraSpace
    Quick Guide | Contact Us
    Open Repository is a service operated by 
    Atmire NV
     

    Export search results

    The export option will allow you to export the current search results of the entered query to a file. Different formats are available for download. To export the items, click on the button corresponding with the preferred download format.

    By default, clicking on the export buttons will result in a download of the allowed maximum amount of items.

    To select a subset of the search results, click "Selective Export" button and make a selection of the items you want to export. The amount of items that can be exported at once is similarly restricted as the full export.

    After making a selection, click one of the export format buttons. The amount of items that will be exported is indicated in the bubble next to export format.