Introduction. Sweet cherries are susceptible to postharvest decay.
The use of synthetic fungicides is discouraged in postharvest handling because they
can leave a residue and present a safety risk. Therefore, naturally occurring compounds
have been considered as an alternative. Fumigation of short-chain organic acids and
essential oils has shown promise in controlling fungal activities. This study reports
their effects on sweet cherries. Materials and method. `Hedelfingen' sweet cherries
(Prunus avium L.) were inoculated with conidia of Monilinia fructicola and
Penicillium expansum, then fumigated with three levels of thymol or acetic
acid for 10 min before cold storage. Results and discussion. After 13 d at 10°C,
sweet cherries fumigated with 10 mg × L-1 of thymol significantly reduced brown rot
from 21% to 12%, but had no effect on reducing blue mold rot. Fumigation with 6
or 10 mg × L-1 acetic acid significantly reduced blue mold rot from 16% to 2%,
but had no effect on reducing brown rot. Fumigation did not have any effect on the
firmness, total soluble solids and titratable acid of the sweet cherries. Fumigation
with 2 or 6 mg × L-1 of thymol did not accelerate stem browning compared with the
control, but fumigation with 10 mg Yen L-1 of thymol caused almost total stem browning.
Fumigation with acetic acid showed no impact on discoloration of the stems. Conclusion.
Thus, fumigation with acetic acid or thymol at low concentrations has a potential use
for postharvest decay control without adverse effects on fruit quality.