The rate of loss of moisture from fresh fruits is largely
dependent on the humidity and temperature of the
surrounding air, as well as on the heat and mass transfer
properties of the fruit. Grape berries don’t show
symptoms of water loss until the damage is quite evident
on the stems. At about 4-5% mass loss, berries feel soft
and above 5% loss in mass the wrinkles start to appear.
However, despite good temperature control during
postharvest storage, table grapes continue to lose mass
mainly due to the micro-climatic conditions that were
created within the enclosed fruit packages. After 75 days
of cold storage the maximum mass loss of berries was
less than10%, while the maximum mass loss of stems
was in the range of 49.2± 4.66% Ngcobo et al., 2012.
Results of this experiment support previous findings that
ethanol treated grapes have beneficial effects in
suppressing decay during the storage time.