There was a decrease in L of the control, 1 min steam-blanched
sample and 1% ascorbic acid, compared to 3, 5 and 7 min steam-
blanched slices, which showed similar values. This situation can
be explained by the fact that PPO and POD are very active initially,
compared to their inactivation as a result of steam blanching. Heat
inactivation of PPO is feasible by applying temperatures over 50 C
but may produce undesirable colours and/or flavours, as well as
undesirable changes in texture