Late season cherry (
Prunus avium
[L.] L.) cultivars have
turned of important relevance in production systems of the
south of Chile with a continuous increase in exports. Cherries
reach final markets after long distance ocean shipping
and pitting damage continues to be the main postharvest
detrimental quality loss during this period. Different factors
affect pitting expression responses during harvest and
postharvest fruit management. The aim of this study was
to determine the influence of postharvest factors in pitting
development of two late cherry ‘Regina’ and ‘Sweetheart’
using an impact energy method. Maturity stage (red and
dark red), impact energy (0.00342 and 0.0107 J) and storage
time (0, 7, 14, 21, 28 d) were evaluated. Fruit composition
(soluble solids, pH, and titratable acidity), weight loss (%)
and firmness were measured. Induced pitting was determined
after allocating a known impact energy level and obtaining an
imprint of the damaged area. Pit diameter, depth and volume
were determined by light microscopy techniques and image
analysis. Pitting damage that occurred naturally on fruit picked
at commercial maturity stage was determined at harvest and
during cold storage. The induced pitting device allowed for the
application of a mechanical injury of known impact energy,
useful to determine pitting susceptibility differences among
cultivars. The coefficient of variation of the method was 0.18
for pit diameter, 0.37 for pit depth and 0.6 for pit volume,
indicating repeatability of results independent of the impact
energy applied or the variety studied. ‘Sweetheart’ showed
higher incidence of induced pitting during storage, with an
average 2.8 pit volume increase compared to a 2.2 increase in
‘Regina’ during the same period. Naturally occurring damage
of commercial fruit verified results obtained with the induced
pitting device, with ‘Sweetheart’ more susceptible than
‘Regina’ (P < 0.05).
