HHP processing constitutes an alternative method to
conventional thermal pasteurisation for the preservation
of refrigerated reconstituted orange juice. In order to
select the most suitable processing conditions, not only
microbiological stability, but also sensory characteristics
must be taken into account, since overpressurisation can
lead to an organoleptically unaccepted product. A high
pressure treatment of 500 MPa at 35 C for 5 min led
to a better retention of ascorbic acid during post processing
storage of orange juice at 0–15 C compared
to conventional thermal pasteurisation (80 C, 30 s).
Ascorbic acid loss of high pressurised juice was found to
have higher temperature dependence than thermally
treated one. Regardless the type of packaging used (intermediate
or high oxygen barrier packages), an extension
of shelf life was achieved for high pressure treated
orange juice compared to thermally pasteurised one.
Immediately after processing, high pressurised orange
juice retained better the flavour of untreated reconstituted
juice, while its sensory characteristics were also
judged superior during storage, compared to thermally
pasteurised juice.