In the second series of experiments, entire clusters
of grapes were harvested, treated, dried, and stored in
ventilated polyethylene (VPE) bags containing about
800–1000 g of grapes each. The clusters were placed
on metal racks as a single layer (out of VPE bags)
and inoculated as described previously. A volume of
100 ml of inoculum was sprayed on to 40 kg clusters.
Inoculated clusters were immersed for 30 s in 10 and
20% (v/v) ethanol solutions alone or in combination
with 0.5 and 1.0% (w/v) potassium sorbate. The fruit
were immersed in the solutions while contained within
the VPE bags. A volume of 5 l of each solution was
used to immerse 4 kg fruit. After treatment, the fruit
were removed from the bags, air dried for about 1 h,
and placed into new VPE bags, placed in fiberboard
boxes, stored at 0–1 ◦C(RH > 90%) for 24 h to facilitate
rapid cooling, then wrapped with polyethylene stretch
film (20m) to minimize weight loss and stem desiccation
and stored for 30 days at 0–1 ◦C (RH > 90%).
SO2 treatment consisted of dual-release generator pads
containing 7 g of sodium metabisulfite (Uvas, Santiago,
Chile). Two generator pads were placed on top
and two beneath the grapes within each box and then,
boxes were enclosed within plastic bags just prior to
storage. The number of decayed berries per kg of fruit
was recorded after storage. Each replicate consisted
four VPE bags containing about 900 g of grapes each.
The experiment was performed twice.