Environmental impact of a traditional cooked dish at four different manufacturing scales: from ready meal industry and catering company to traditional restaurant and homemade

The environmental burdens of the same dish (a traditional hot stew with pulses and pieces of pork sausages and ham) cooked at four different production scales was analyzed by life cycle assessment (LCA): (a) canned, industrially manufactured and consumed at home; (b) catering company, serving the product for schools; (c) restaurant, cooked in a traditional way and served; and (d) homemade, cooked, and consumed at household level. The LCA methodology was applied following the ISO 14044:2006 guidelines. For the inventory analysis, industrial data were obtained from a ready meals factory. Other primary data were directly obtained from the systems analyzed (catering, restaurant and homemade levels). Databases (Ecoinvent, LCA Food DK, BUWAL250, IDEMAT 2001, ETH-ESU 96) were used together with the SimaPro v7.3.3. For the impact assessment, the Eco-indicator 99 method and the CML 2 baseline method were used. In cases (c) and (d), different scenarios for the origin of raw materials and source of energy for cooking were considered. In level (a), an additional scenario considering a 50% reduction of food wastes was also investigated. The main contribution was meat ingredients, followed by energy consumption. Despite the higher environmental loads in transportation, the factory showed an environmental performance similar to cooking at home with gas. These results can be explained by the implementation of heat recovery systems at industrial scale. The restaurant showed the worst environmental performance. The main reason was that all the energy consumed in the restaurant (even not directly related to cooking) was attributed to the exclusive purpose of serving the food, since no other activities were carried out in the business. Consumer's choices such as the preference for eating in a restaurant or the energy used for cooking turned out to be important differentiating factors. LCA allowed critical aspects to be identified in order to improve sustainable food production and consumption patterns. Electricity consumption and the amount of wastes sent to landfill turned out to be critical control points. In the case of complex dishes such as stews, the higher scale systems in the study (the factory and catering company), with proper energy and environmental practices, can have lower environmental burdens than small-scale systems, such as homemade cooking using a ceramic-glass cooktop or consumption in traditional restaurants. To reinforce the role of education, specific programs on the need to save food and the environmental impact of dietary choices must be implemented at schools.