The difference in
the results of these studies could be attributed to variations in
the temperature and time combinations used. In general, when
the thermal treatment was short (in the order of seconds) the
ascorbic acid content was maintained and the vitamin decay was
higher for the high-pressure treated samples. In the present study,
milk treatment at 62.5 C for a long time (30 min) led to higher
vitamin C decay than after the short pressurisation treatment
(5 min) at lower temperature (12 C). The total vitamin C and
ascorbic acid retentions were the same in the three HPP treatments
tested. According to the reviewed literature, temperature and time
seem to determine the degree of vitamin C loss in HPP processed
food, while pressure level does not exert a significant effect (Houska
et al., 2006).