Antioxidant activities, sensory and anti-influenza activity of grape skin tea infusion

Alaa El-Din A Bekhit; Vern Jou Cheng; Michelle McConnell; Jenny H Zhao; Richard Sedcole; Roland Harrison

doi:10.1016/j.foodchem.2011.05.032

Antioxidant activities, sensory and anti-influenza activity of grape skin tea infusion

Food Chem. 2011 Dec 1;129(3):837-45. doi: 10.1016/j.foodchem.2011.05.032. Epub 2011 May 14.

Authors

Alaa El-Din A Bekhit¹, Vern Jou Cheng², Michelle McConnell³, Jenny H Zhao⁴, Richard Sedcole⁴, Roland Harrison⁴

Affiliations

¹ Department of Food Science, Division of Sciences, University of Otago, P.O. Box 56, Dunedin, New Zealand. Electronic address: bekhita2@lincoln.ac.nz.
² Department of Food Science, Division of Sciences, University of Otago, P.O. Box 56, Dunedin, New Zealand.
³ Department of Microbiology and Immunology, Division of Health Sciences, University of Otago, P.O. Box 56, Dunedin, New Zealand.
⁴ Agriculture and Life Sciences Division, Lincoln University, P.O. Box 84, Canterbury, New Zealand.

PMID: 25212307
DOI: 10.1016/j.foodchem.2011.05.032

Abstract

Grape skin extracts from pinot noir and pinot gris exhibited significant in vitro antiviral (influenza virus) activity. Five tea infusions from grape skins (Vitis vinifera var. pinot noir and pinot gris) without any additives (control pinot noir and control pinot gris) or by adding variable amounts of green tea and hibiscus were investigated as a means to utilise wine wastes. The antioxidant activities (DPPH scavenging capacity and superoxide anion radical scavenging capacity), total phenolics, the polyphenolics profile and objective colour measurements (CIELab) were determined on freeze-dried water extracts of all five tea infusions, hibiscus and green tea. The colour parameters, L(∗) and a(∗) values, varied widely (P<0.05) for all the infusions as a result of having different levels and variety of pigments. The tea infusions exhibited weak antioxidant activity and the antiviral activity in grape skin appears not related to phenolics contents.

Keywords: Antioxidant; Antiviral; Grape skin; Sensory; Tea.