Management of Food Waste Produced in Food Service Units in the City of São Paulo

Background: Food Service Units (FSUs) play a key role in large-scale meal provision but face significant challenges related to food waste management and environmental sustainability. Objective: To evaluate food waste generation in FSUs and investigate its association with operational factors and nutritionists’ knowledge of sustainability practices. Methods: A cross-sectional observational study was conducted in 30 FSUs belonging to a single food service company in São Paulo, Brazil. Data were collected through a structured questionnaire administered to unit nutritionists and through direct measurement of food waste. Waste was categorized into pre-preparation, overproduction, expired food, and plate waste. Measurements were performed using calibrated digital scales. Descriptive and inferential statistical analyses were conducted using non-parametric tests, with correlations assessed via Spearman’s coefficient. Results: Median total waste was 54,718 units (IQR: 32,891–81,502). Strong correlations were observed between total waste and overproduction (ρ = 0.93; p < 0.001) and pre-preparation waste (ρ = 0.85; p < 0.001). Moderate correlations were found with number of meals served and number of employees. No statistically significant association was observed between nutritionists’ knowledge and total waste. Conclusions: Operational factors, particularly production-related waste, are the main contributors to total food waste in FSUs. Although no direct association with nutritionists’ knowledge was observed, improving management practices and production planning may significantly reduce waste.