Heat-Dependent Desorption of Proanthocyanidins from Grape-Derived Cell Wall Material under Variable Ethanol Concentrations in Model Wine Systems

Jordan W Beaver; Konrad V Miller; Cristina Medina-Plaza; Nicolas Dokoozlian; Ravi Ponangi; Thomas Blair; David Block; Anita Oberholster

doi:10.3390/molecules24193561

Heat-Dependent Desorption of Proanthocyanidins from Grape-Derived Cell Wall Material under Variable Ethanol Concentrations in Model Wine Systems

Molecules. 2019 Oct 1;24(19):3561. doi: 10.3390/molecules24193561.

Authors

Jordan W Beaver^{1

2}, Konrad V Miller³, Cristina Medina-Plaza⁴, Nicolas Dokoozlian⁵, Ravi Ponangi⁶, Thomas Blair⁷, David Block⁸, Anita Oberholster⁹

Affiliations

¹ Department of Chemistry and Biochemistry, University of Texas at Tyler, 3900 University Blvd, Tyler, TX 75707, USA. jbeaver@uttyler.edu.
² Department of Viticulture and Enology, University of California, One Shields Avenue, Davis, CA 95616, USA. jbeaver@uttyler.edu.
³ Department of Viticulture and Enology, University of California, One Shields Avenue, Davis, CA 95616, USA. vonmiller@ucdavis.edu.
⁴ Department of Viticulture and Enology, University of California, One Shields Avenue, Davis, CA 95616, USA. cmedinaplaza@ucdavis.edu.
⁵ E&J Gallo Winery, 600 Yosemite Blvd, Modesto, CA 95354, USA. nick.dokoozlian@ejgallo.com.
⁶ E&J Gallo Winery, 600 Yosemite Blvd, Modesto, CA 95354, USA. ravi.ponangi@ejgallo.com.
⁷ E&J Gallo Winery, 600 Yosemite Blvd, Modesto, CA 95354, USA. tom.blair@ejgallo.com.
⁸ Department of Viticulture and Enology, University of California, One Shields Avenue, Davis, CA 95616, USA. deblock@ucdavis.edu.
⁹ Department of Viticulture and Enology, University of California, One Shields Avenue, Davis, CA 95616, USA. aoberholster@ucdavis.edu.

Abstract

Desorption of proanthocyanidins (PA) from grape cell wall material (CWM) was investigated in solutions of varying ethanol concentrations and increasing temperature. The results reveal the reversibility of PA-CWM interactions and the role that temperature and ethanol concentration play in the extent of PA desorption. Sequentially raising temperature from 15 to 35 °C resulted in desorption of up to 48% of the initial adsorbed PA. A comparison to a phenolic extraction model showed significant differences between the predicted and actual amount of PA that desorbed from the CWM. This suggests that the initial conditions of temperature and ethanol concentration must be considered when estimating PA extraction in red wine production. Under typical winemaking conditions, a significant amount of PA may be irreversibly adsorbed if exposed to CWM at low temperature (i.e., cold soak). A compositional analysis suggests the selective desorption of large molecular weight PA from CWM under all experimental conditions. Additionally, a preferential desorption of skin-derived PA over seed-derived PA was noted in the absence of ethanol.

Keywords: cell wall material; desorption; ethanol; fermentation; grape; modeling; proanthocyanidins; temperature; wine.

MeSH terms

Cell Wall / chemistry*
Ethanol / chemistry
Hot Temperature
Molecular Weight
Proanthocyanidins / chemistry*
Vitis / chemistry
Wine / analysis*

Substances

Proanthocyanidins
Ethanol