Related Experiment Video
Updated: Feb 12, 2026
07:05
Author Spotlight: Eco-Friendly Extraction of Bioactive Compounds Using Polyol-Based Microwave-Assisted Techniques
Published on: August 23, 2024
2.9K
Characterization of Phenolic Compounds in Wine Lees
Ye Zhijing1,2, Amin Shavandi3, Roland Harrison4
1Department of Food Sciences, University of Otago, Dunedin 9054, New Zealand. Victor.Ye@lincolnuni.ac.nz.
Antioxidants (Basel, Switzerland)
|March 29, 2018
Summary
Wine lees, rich in tannins, exhibit significant antioxidant activity influenced by winemaking methods. Red wine lees, particularly Pinot Noir, show higher antioxidant capacity, suggesting potential health applications.
Area of Science:
- Enology
- Food Chemistry
- Natural Products
Background:
- Wine lees, a byproduct of winemaking, contain valuable phenolic compounds.
- Understanding the impact of vinification on lees' properties is crucial for valorization.
- Antioxidant activity of wine lees is not fully characterized.
Purpose of the Study:
- To investigate the effect of vinification techniques on phenolic compounds and antioxidant activity of wine lees.
- To compare antioxidant properties of white and red wine lees.
- To identify key phenolic compounds responsible for antioxidant activity.
Main Methods:
- Determined total phenol content (TPC), total tannin content (TTC), and mean degree of polymerization (mDP).
- Analyzed predominant terminal and extension units of polymeric proanthocyanidins.
- Assessed antioxidant activity using ORAC and DPPH assays.
Main Results:
- Vinification techniques significantly impacted TPC and TTC (p < 0.05).
- White wine lees exhibited higher mDP than red wine lees.
- Red wine lees demonstrated stronger antioxidant activities (ORAC/DPPH correlation).
- Catechin and epicatechin were predominant units; epigallocatechin in white lees, epicatechin in red lees.
Conclusions:
- Tannins are major phenolic compounds in wine lees with significant antioxidant potential.
- Red wine lees, especially Pinot Noir, possess high antioxidant capacity.
- Wine lees can be a valuable source for human and animal health applications.
More Related Videos
Related Concept Videos
01:17Oxidation of Phenols to Quinones
4.8K
In the presence of oxidizing agents, phenols are oxidized to quinones. Quinones can be easily reduced back to phenols using mild reducing agents. The electron-donating hydroxyl group enhances the reactivity of the aromatic ring, enabling oxidation of the ring even in the absence of an α hydrogen.
o-hydroxy phenols are oxidized to o-quinones and p-hydroxy phenols to p-quinones. Such redox reactions involve the transfer of two electrons and two protons. The reversible redox...
o-hydroxy phenols are oxidized to o-quinones and p-hydroxy phenols to p-quinones. Such redox reactions involve the transfer of two electrons and two protons. The reversible redox...
4.8K
02:38Molecules and Compounds
69.4K
Atoms and Molecules
69.4K
02:23Structure and Nomenclature of Alcohols and Phenols
22.5K
Overview
Alcohols are one of the most important functional groups in organic chemistry. The name of alcohol comes from the hydrocarbon from which it is derived. Alcohols are organic molecules containing the functional hydroxyl or –OH group directly bonded to carbon. Phenols have an OH group directly attached to a benzene ring. While alcohols are colorless, phenol is a white crystalline compound with a characteristic "hospital smell" odor.
As with other organic compounds, alcohols and...
Alcohols are one of the most important functional groups in organic chemistry. The name of alcohol comes from the hydrocarbon from which it is derived. Alcohols are organic molecules containing the functional hydroxyl or –OH group directly bonded to carbon. Phenols have an OH group directly attached to a benzene ring. While alcohols are colorless, phenol is a white crystalline compound with a characteristic "hospital smell" odor.
As with other organic compounds, alcohols and...
22.5K
02:32Physical Properties of Alcohols and Phenols
16.8K
Alcohols are organic compounds in which a hydroxy group is attached to a saturated carbon. Phenols are a class of alcohols containing a hydroxy group attached to an aromatic ring. The physical properties of the alcohols and phenols are influenced by hydrogen bonding due to the oxygen–hydrogen dipole in the hydroxy functional group and dispersion forces between alkyl or aryl regions of alcohol and phenol molecules.
Alcohols possess a higher boiling point than aliphatic hydrocarbons of similar...
Alcohols possess a higher boiling point than aliphatic hydrocarbons of similar...
16.8K
03:02Organic Compounds
57.6K
All living things are formed mostly of carbon compounds called organic compounds. The category of organic compounds includes both natural and synthetic compounds that contain carbon. Although a single, precise definition has yet to be identified by the chemistry community, most agree that a defining trait of organic molecules is the presence of carbon as the principal element, bonded to hydrogen and other carbon atoms. However, some carbon-containing compounds such as carbonates, cyanides, and...
57.6K
02:36Acidity and Basicity of Alcohols and Phenols
22.2K
Like water, alcohols are weak acids and bases. This is attributed to the polarization of the O–H bond making the hydrogen partially positive. Moreover, the electron pairs on the oxygen atom of alcohol make it both basic and nucleophilic. Protonation of an alcohol converts hydroxide, a poor leaving group, into water—a good one. The two acid–base equilibria corresponding to ethanol are depicted below.
22.2K