## 4 Environmental Footprint and Life Cycle Assessment in Cheese Production
The standards ISO 14040:2006 (LCA-Principles and framework) and ISO 14044:2006 (LCA-Requirements and guidelines) are internationally validated methodologies that provide the necessary guidelines for applying LCA to a wide range of processes and products. The main difference between the two standards is that ISO 14040:2006 outlines the principles and framework of an LCA study, while ISO 14044:2006 provides the guidelines and requirements for conducting the assessment [38]. According to these standards, LCA is structured into four main phases: (i) the definition of the objective and scope; (ii) the inventory analysis (LCI); (iii) the impact assessment (LCIA); and (iv) the interpretation of the results. In defining the objective and scope, the boundaries of the system and the processes included are established. LCI involves collecting quantitative data on input and output flows, with modelling in specific software. When there is co-production, it is necessary to apply criteria for allocating environmental impacts, preferably avoiding allocation through subdivision or the expansion of the system. As the use of the LCA method became more widespread, the need for a complementary technique arose to ensure data robustness and the reliability of the conclusions. The study by [PERSON] et al. [39] applied LCA to cheese and whey production, following ISO 14040 and ISO 14044. The system covered all stages, from milk production to final disposal, and, in the case of whey, up to its delivery to the first customer. Whey was treated as a co-product, requiring the allocation of impacts based on ISO guidance. The main method used was mass allocation, considering milk solids as the relevant basis. When more detailed data were available, allocation was conducted by engineering estimates or by revenue, depending on the nature of the input. These choices affect the share of environmental impact assigned to whey and, by extension, to cheese, particularly in categories such as energy demand and eutrophication. Selecting appropriate allocation criteria, as defined by ISO 14044, helps to improve consistency and comparability in LCA studies involving dairy products. Another important element of these methodologies is the use of databases such as \"Ecoinvent\", a comprehensive source that provides inventory and input-output data for a variety of processes and services. Although access to its content requires a license, \"Ecoinvent\" is adopted by academic institutions and private companies, allowing the comparison of data and facilitating the rapid calculation of components belonging to the study being analyzed [38]. However, it should be noted that part of the datasets are based on generalized European conditions, which may not fully include regional variations in production processes, energy sources, or the lower production scales typical of artisanal production, thus influencing the accuracy and transferability of the results when applying the database outside its primary context. As environmental analysis has become increasingly necessary, specific indicators for each resource have emerged, such as the energy footprint, carbon footprint, and water footprint. These indicators now complement LCA and are also supported by alternative tools, such as environmentally extended input-output (EEIO) analysis, expanding the analytical scope of environmental assessments in the cheese sector [40].