Life cycle assessment of the production of an extruded dog food in Brazil

Sustainability is the current focus of the scientific community, governments, and companies in various market segments, such as pet food. Pet food production has increased rapidly in recent years, with a trend toward the development of environmentally friendly products and processes. The first step in creating strategies for mitigating environmental impacts is to assess key points in manufacturing processes. Given this, this study aimed to perform a life cycle assessment (LCA) to estimate the environmental impacts associated with the formulation, production, and distribution phases of an extruded dog food produced in Brazil. System boundaries were from cradle-to-gate, encompassing extraction of raw materials, transportation, processing, production, packaging, and distribution. Estimates were based on the amount of food required to meet the energy requirements for maintenance of a 10 kg dog (functional unit = 2.59 MJ day- 1, reference flow = 177.3 g day- 1). Environmental impacts were calculated by the environmental footprint method (EF 3.0 v. 1.00) using SimaPro software (v. 9.1.1.1). Product ingredients and packaging materials were modeled under Brazilian conditions using ecoinvent 3.7.1 and Agri-footprint 5.0 databases. Data regarding transportation, processing, distribution, electric and thermal power generation, water usage, and waste generation were obtained from the company's records (2019-2020). In this study, as expected, formulation was the most relevant factor, accounting for 70%-90% of the total environmental impacts. The main impact categories were terrestrial and marine eutrophication, acidification, particulate matter, and climate change (80% of total impacts). Production of the evaluated dog food was associated with the emission of 88.73 kg CO2 eq year- 1 or 1.37 kg CO2 eq kg- 1 distributed food. The use of animal meals (poultry by-product meal and meat and bone meal) and vegetable by-products (wheat bran and rice bran) contributed to reducing environmental impacts. Therefore, in this study, ingredient selection was considered the most important factor in mitigating the environmental impacts of pet foods. As the overall impact of the formulation depends on data on the use stage, such as nutrient excretion after consumption, future studies should adopt a cradle-to-grave approach for a better comprehension of the feasibility of applying animal and vegetable by-products in the eco-design of pet food products.