## 6 Carbon Footprint  
Like other environmental metrics, the carbon footprint is a specific indicator used to quantify the emission of greenhouse gases (GHGs). According to [PERSON] et al. [47], carbon dioxide (CO\({}_{2}\)), primarily originating from the burning of fossil fuels and industrial activities, is the largest contributor to global warming, followed by methane (CH\({}_{4}\)), which is largely emitted by agriculture and livestock. Another important group of GHGs includes nitrogen oxides (NOOx), which, although emitted in smaller quantities, also contribute to the increase in atmospheric temperature [48]. These indicators have been developed to achieve more reliable results, despite the complexity and variability of GHG emissions. They can be applied to processes and products, and can even be used to determine the amount of GHGs emitted by a nation, providing greater accuracy in the implementation of strategies to mitigate environmental impacts. In the context of cheese production, the carbon footprint is most significant during the milk production stage, accounting for 86% of the emissions [33]. Enteric methane (CH\({}_{4}\)) emissions from ruminants are a major contributor to the carbon footprint of milk production. According to [PERSON] et al. [49], dietary modifications-such as replacing conventional forages with high-sugar grasses-can help to reduce CH\({}_{4}\) emissions. These strategies act on the fermentation process in the rumen, influencing microbial activity, thus reducing methane output. This type of intervention complements broader sustainability measures at the farm level, contributing to the reduction of the GHG emissions associated with dairy supply chains. In the context of the cheese industry, refrigeration is responsible for a significant portion of the emissions associated with the product's life cycle. According to [PERSON] et al. [33], energy consumption during storage and distribution can account for up to 6% of the total CO\({}_{2}\) eq. emissions related to cheese production. Moreover, as noted by [PERSON] et al. [49], the refrigeration systems used in the stages following milk production are electricity-dependent, which further increases emissions when non-renewable energy sources are utilized. The discussions around climate change and its causes have raised concerns across various industrial sectors, including the food industry, leading to increased research into technologies that reduce GHG emissions. Several LCA studies have been carried out with the objective of quantifying GHG emissions across diverse geographical and technological contexts. Table 3 summarizes some of the results from different case studies, expressed in kilograms of CO\({}_{2}\) equivalent per kilogram of product. However, the studies used in Tables 2 and 3 adopted different LCA boundaries and analytical frameworks, which can influence the reported values and should be considered when comparing results across sources. Similarly to what was observed in the analysis of energy consumption, the GHG values associated with cheese production vary depending on factors such as the type of product, the complexity of the production process, the definition of system boundaries (LCA), and the technological and geographical characteristics of the units analyzed. In addition, in the case of emissions, the origin of the energy used, the inclusion of credits for co-products (such as the use of whey), and the specific methodologies adopted in each study also have an influence. The variations observed between the cases reflect both structural differences in the production systems and methodological choices in the design of the inventories and borders, which is why the results reported are only comparable when contextualized from this perspective. In summary, applying the LCA methodology to the cheese industry provides a detailed and structured framework for assessing the environmental impacts of each stage of the production process.