Orange juice showed a higher vitamin C content than
gazpacho in both cases, HIPEF-treated and untreated. In
addition, orange juice also exhibited greater vitamin C
retention than did gazpacho (p < 0.05) (Figs. 1–4). These
differences may be due to the lower pH of orange juice
(3.58) than gazpacho (4.36), as more acidic conditions are
known to stabilize ascorbic acid (Tannebaum, Archer, &
Young, 1985). In addition, Gregory (1996) reported that
the degradation of ascorbic acid seems to be influenced
by many compounds which are involved in the oxidation
reaction of vitamin C. Therefore, the influence of HIPEF
on other orange juice and gazpacho compounds could
affect the degradation of vitamin C and, thus, the levels
of vitamin C retention.