What is the carbon footprint of food waste? results from an analysis in a hospital canteen in northeast Italy

Background and Objective: Attention to economically and environmentally sustainable development has increased in recent years. Fundamental, in pursuing these goals, is attention to reducing food waste, which accounts for about one third of global production. The aim of this study was to evaluate the food waste generated by consumers in a hospital canteen in Italy. Methods: We analyzed the meals of workers who accessed a northeastern Italian hospital canteen. We photographed trays before and after the consumption for five days in September 2022. We used a modified Comstock visual scale to estimate remaining food, and we estimated the carbon (CF) and water footprints (WF) of food waste using Barilla’s SU-EATABLE LIFE database. Results: We took before and after meal photos of 240 meals. A total of 188 meals (78%) were completely consumed, while 52 of them had waste left over. Food waste accounted for 2% of the total foods served. The average food waste per tray of leftovers was 10% and consisted mainly of salad. On average, 14 g CO2eq./ tray (CF) and 15 LH2O/tray (WF) were generated by the wasted portion of the meal. The median value was 0(0–0) for both CF and WF. A total of 3.3 kg CO2eq. was generated for the production of discarded foods, which is approximately equivalent to a 16.5 km car trip. Conclusion: This study was able to establish that, despite the virtuous behavior of most of the consumers, waste in the observed hospital canteen was limited but not negligible. The degree of personalization of the portions offered by the canteen staff in addition to the standard portion could justify the small amount of food waste. In the future, it would be interesting to consider not only the waste generated by users, but also that one generated during preparation and serving.