INTRODUCTION:
Food waste in canteens includes food served but not consumed (plate waste, PW) and leftovers on the counter after service (counter food waste, CFW). The study aim was to characterize PW in terms of weight, energy, environmental indicators, and food categories, and to quantify CFW in three hospital canteens in the province of Udine (northeastern Italy).

METHODS:
During a reference week in September 2023, user trays in three hospital canteens (C1, C2 and C3) were photographed before and after lunch. A modified Comstock visual scale was used to assess PW, and the SU-EATABLE Life database was used to estimate its environmental indicators. To evaluate CFW, leftover dishes on the canteen counter were weighed at the end of service.

RESULTS:
A total of 1,624 trays were analyzed, of which 1,005 were in C1, 348 in C2, and 271 in C3. Of these, 59%, 79%, and 75% were fully consumed (zero PW), respectively. Side dishes were the main wasted food category in all canteens, accounting for 20-37% of total PW. The largest canteen (C1) reported the highest values of PW (44.3 g/tray, 58.7 kcal/tray) and the worst sustainability values, with a carbon footprint of 93.4 g CO2 eq./tray and a water footprint of 83.7 L H2O/tray. Considering the analysed trays, the PW accounts for approximately 113 kg of CO2 and 80,245 wasted kcal. Approximately 66 kg of CFW were weighed in C1, 101 kg in C2, and 8 kg in C3.

CONCLUSIONS:
The environmental impact of PW and CFW in hospital canteens should be considered in addition to energy and nutrients waste. In line with the European Green Deal, improvement strategies should address the 3 Rs of food waste: Reducing plate waste, Reusing leftovers or donating surplus food, and Recycling by composting or sending scraps for energy recovery or feed production.