found total inactivation of PG and contradictory behaviour of PME
at some pressure/temperature conditions (500–800 MPa/20–90 °C).
Colour retention is also very important quality attribute of tomato
juice. It is established that pH has an important effect on pigments and
responsible for the colour of fruits and vegetables during processing
(Andres-Bello, Barreto-Palacios, Garcıa-Segovia, Mir-Bel, & Martinez-
Monzo, 2013), but the impact of reducing pH on the maintenance of
tomato juice quality has not been widely investigated.