Interesting comparisons emerged between the two beetroot juices
following FRAP analysis. The first beetroot juice, Eden organic, is
produced by combining pure beetroot juice with lactic acid fermented
beetroot juice and ascorbic acid as a preservative. The second, James
White organic beetroot juice (‘Beet it’), is made from 90% pressed
beetroots and 10% pressed apple juice. Initially Eden organic beetroot
juice displayed a higher FRAP value (9500 μmol/L) than the JamesWhite
juice (8355 μmol/L). Principally due to the higher beetroot content,
since beetroot has a higher FRAP value compared to apple juice (Ryan &
Prescott, 2010), and perhaps in part to the addition of ascorbic acid, a
powerful reducing agent in itself. This trend is continued after the gastric
phase where the Eden organic juice increased almost 2 fold to
18,639 μmol/L and the James White juice, similar in magnitude,
increased to 15,014 μmol/L. Following the duodenal phase of digestion
where the pH is first adjusted to 5.3 and then to 7.4 following the
addition of bile salts and pancreatin, both juices show a decrease in
FRAP. The James White beverage remains well above pre-digestion at
12,397 μmol/L. The Eden beverage however, displayed a reducing
capacity that fell below even its pre-digestion value (8890 μmol/L).