The European chestnut (Castanea sativa Mill.) is a typical seasonal product with high importance in Portugal. Due to the difficulty in finding labour to harvest this fruit, machines have been used that perform the harvesting mechanically. However, during the nut's mechanical collection, small stones or other materials can also be sucked, damaging the nut's surface. These damages may affect the quality of the fruit and possibly lead to the appearance of a more significant number of rotten fruits. Currently, the presence of chestnut rot caused by the fungus Gnomoniopsis smithogilvyi (Gnomoniaceae, Diaporthales) has been reported. This study aimed to evaluate the effect on the quality of chestnuts manually and mechanically harvested during industrial cold storage for three months. Parameters such as the presence of bruises and minor cuts, the number of rotted fruits, loss of weight, total soluble solids (TSS), titratable acidity (TA) and reducing sugars were determined. The mechanical harvesting increased the frequency of bruises and small visible cuts. Moreover, in many fruits, it was observed the removal of the tuft. The number of rotted fruits did not increase along the storage time. During the three months of storage, the weight loss was never more than 10%, but it increased over time. Between manual and mechanical harvesting, no significant differences in the weight loss, TSS and TA were observed in almost all situations. The reducing sugars were less than 0.65 g glucose / 100 g d.m., being fluctuations observed over time but without a definite trend. In conclusion, mechanical harvesting cause minor damages to the chestnut surface. Still, in the physicochemical parameters evaluated, there were no significant differences between the two types of harvesting in the majority of the situations.
