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Updated: May 31, 2026
05:57
Quantitative 31P NMR Analysis of Lignins and Tannins
Published on: August 2, 2021
Relationship between red wine grade and phenolics. 2. Tannin composition and size
Stella Kassara1, James A Kennedy
1The Australian Wine Research Institute, Glen Osmond, SA, Australia.
Journal of Agricultural and Food Chemistry
|June 28, 2011
Summary
Higher concentrations of skin-derived tannins in red wines (Vitis vinifera L. cv. Shiraz) correlate with increased projected bottle price. This suggests optimizing skin tannin levels can enhance wine value.
Area of Science:
- Enology and Viticulture
- Food Chemistry
- Agricultural Economics
Background:
- Commercial red wines, specifically Vitis vinifera L. cv. Shiraz from the 2009 vintage, were assessed for quality grading.
- Phenolic compounds, crucial for wine color and structure, were analyzed.
Purpose of the Study:
- To investigate the relationship between phenolic composition, particularly tannins, and the projected market value of red wines.
- To determine if specific tannin characteristics influence wine grade and price.
Main Methods:
- Winemaker assessment for allocation grade.
- Phenolic analysis including total anthocyanins, non-bleachable pigment (SO(2)), and wine color density.
- Tannin analysis focusing on concentration, composition, and average degree of polymerization.
Main Results:
- A positive correlation was observed between overall wine phenolic concentration and projected bottle price.
- Skin-derived tannins were specifically linked to wine grade.
- Higher concentrations or proportions of skin tannins were associated with increased projected wine price.
Conclusions:
- Wine phenolic content, especially tannins derived from grape skins, is a significant factor in determining wine value.
- Maximizing skin tannin concentration and/or proportion may lead to higher projected bottle prices for Shiraz red wines.
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