With growing evidence that links antioxidant-rich diets with better long-term health, and further evidence that oxidative stress is a factor in age-related declines, more consumers are seeking foods that are naturally rich in antioxidants.
A newly published study in the Journal of Agriculture and Food Chemistry suggests grape juice made from Concord grapes may be an outstanding source among popular juices and juice drinks.
According to the study, Welch’s Purple Grape Juice delivered the highest antioxidant capacity and contained the highest total and broadest range of polyphenol antioxidants among 13 popular U.K. juices and juice drinks tested.
Researchers at the University of Glasgow Scotland used High Performance Liquid Chromatography (HPLC) and Mass Spectrometry (MS) to identify and quantify individual phenolic compounds in the fruit juices and juice drinks.
Additional analysis included the Folin-Ciocalteu assay to measure the phenolic content of the juices and the Oxygen Radical Absorbance Capacity (ORAC) assay to measure the antioxidant capacity. Antioxidant capacity and variety of polyphenol antioxidant compounds varied by flavor.
This is the second study in less than a year that demonstrates the superior antioxidant capacity of Concord grape juice. In July 2006, an independent study published in the American Journal of Clinical Nutrition ranked Welch’s 100% Grape Juice made from Concord grapes as the number one beverage for antioxidant capacity per serving among over 1,000 U.S. foods and beverages tested.
“Antioxidants are bioactive compounds in foods that play an active role in the human body,” explained Professor Alan Crozier, Professor of Plant Biochemistry and Human Nutrition at the University of Glasgow.
“By quenching free radicals, they help maintain oxidative balance and may very well be responsible for improving and maintaining health. Polyphenols are a potent natural group of antioxidants, which are believed to play a role in protecting against chronic diseases.”
“While there is growing awareness of the importance of antioxidants, and in turn polyphenols, this research highlights the importance of also considering the individual type of compounds you are consuming, because each has different health benefits,” continued Crozier.
The University of Glasgow researchers suggest that the health benefits of polyphenols may be best achieved by consumption of a range of juices, consisting of purple grape juice in combination with grapefruit, cranberry and cloudy apple juice. This is because purple grape juice is a rich source of a wide variety of polyphenols, and particularly high in powerful flavanols and anthocyanins, while grapefruit, cranberry and cloudy apple juice are high in other specific polyphenols.