'EariiGrande' peach (Prunus peTSiea L.) fruits were harvested at the firm ripe
stage from a private farm In Ismallla Govemorate. Fresh-cut slices and whole peach
fruits were exposed to 0,5,10,15,20, and 25 min UV·B (310 nm) exposure time in
two successive seasons (2000 and 2001). A 30 min UVexposure time was added to
the treatments in the second season. Slices and whole fruits were stored at 2·C after
badting. The objectives were to detennine the optimum UV exposure time for fresh-
cut slices and whole peach fruits and its effect on quality, storabillty, and decay ('Yo) of
the slices and the whole fruits. In both seasons, ultraviolate (W·B) treatments (15 - 25 min) revealed a
maintenance In peach fresn.eut slices 'L', 'a', and 'b' colour values relative to the
control. This means that W suppressed the onset of ripening process in respect to
colour. However, during storage at 2·C, 'L' and 'a' colour values increased especially
after 8-day of storage while 'b' value did not change in the first season and decreased
in the second one. For the whole fruits, 'L' and 'a' colour values were maintained as a result of
the UV treatments relative to the control. However, 'b' value decreased by the 10 - 20
min treatments. Duling storage, 'L' (brightness indicator) value maintained similar to
the control up to 30 days then decreased. However, 'a' and 'b' values of the whole
peach fruits were decreased. UV-B exposure time 15, 20, and 25 min reSlJlted in the lowest decay percent. In addition, 10 - 25 min UV treatments revealed a reduction in the fresh-cut slices
firmness while 5 min exposure time had no effect on the firmness. Also, no changes
were observed in the whole fruit lIrmness as a resuft of the W treatments. Both fresh-
cut and whole fruit firmness was decreased during storage in both seasons. Acidity In the juice of the fresh-eut peach slices and whole fruits did not
change by the UV treatments relative to the control. Although SSC of the fresh-cut
slices did not change by the treatments, sse of the whole fruits increased relative to
the control. Acidity and SSC increased during storage of the slices and the whole
peach fruits. In addition to that, UV treatments resulted in an increase in weight loss of
the whole peach fruits during storage in both seasons. Sweetness and overall flavour of peach slices were improved by the
treatments while crispness and astringency did not change significantly relative to the
control. During storage, sweetness and overall flavour improved while crispness and
astringency decreased.