Given the higher concentration of pigments in the outer layers of avocado tissue ( ashton et al.,2006), it is perhaps surprising that the effects of HPP on colour were greater on colour were greater on the inside of the slices (yellow tissue) than the back (green tissue). A possible reason for this might be the higher dry matter of the outer tissues (Schroeder, 1985), which with the higher oil content might make it more tolerant to high pressure.