Life-Cycle Assessments of Meat-Free and Meat-Containing Diets by Integrating Sustainability and Lean: Meat-Free Dishes Are Sustainable

Nowadays, sustainable food choices are taking on an increasingly central role. This paper assesses the environmental loads and energy resources of meat-free (vegan and pescovegetarian) and meat-containing (traditional) restaurant soups and main dishes. The applied life-cycle assessment focuses on determining environmental loads and energy resources in restaurant products’ preparation, cooking, and end-of-life phases. Mann–Whitney and Kruskal–Wallis statistical methods were applied to investigate restaurant products’ distribution and carbon footprints. Furthermore, a sustainability assessment model was developed by integrating green-lean and life-cycle assessment approaches called “GreenCycLEAN”. Based on the analysis results, the whole life cycle of meat-free dishes has a lower environmental impact. However, the primary energy requirement of a vegetable soup is less favorable than that of a meat-containing soup. The preparation phase has higher burdens, and the cooking phase is the most energy intensive. Research results are helpful for the sustainability of catering establishments.