Em. Odonoghue et al., DEVELOPMENTAL AND RIPENING-RELATED EFFECTS ON THE CELL-WALL OF PEPINO(SOLANUM-MURICATUM) FRUIT, Journal of the Science of Food and Agriculture, 73(4), 1997, pp. 455-463
Several cell wall components in ripening pepino fruit have been quanti
tatively and qualitatively characterised, with the aim of identifying
their contributions to the loss of tissue firmness. Pepinos were grade
d into nine groups based on progressive, characteristic skin colour ch
anges, previously shown to correspond with decreasing fruit firmness.
While fruit softening began when the pepinos were still green but with
newly acquired purple stripes, the first significant quantitative sig
ns of cell wall modification (total pectin and hemicellulose content d
eclining and CDTA-soluble pectin content increasing, on a fresh weight
basis) were detectable later in ripening, when the fruit began to acq
uire yellow skin pigmentation. Gel fractionation studies demonstrated
that there were increased levels of low-molecular-weight pectin and xy
loglucan during pepino ripening. The change in molecular weight distri
bution of CDTA-soluble pectin occurred as fruit started to acquire yel
low pigmentation, while xyloglucan polymers were modified at an earlie
r stage that coincided with the initial loss of firmness.