Life Cycle Assessment of Amiata Donkey Milk

Donkey milk production is an emerging livestock sector in Europe. However, information on its environmental sustainability remains limited. The present study aimed to quantify the potential environmental impacts of donkey milk production through a life cycle assessment (LCA) and to identify the main processes contributing to its environmental burden. We evaluated the influence of the methodological choice on the environmental performance of donkey milk by three allocation approaches: mass, economic, and reference allocation. The assessment followed ISO 14040 and ISO 14044 standards using a cradle-to-farm-gate approach, with 1 kg of raw donkey milk as the functional unit. Primary data were collected during the 2021–2022 production season, while secondary data were obtained from the Ecoinvent 3.9.1 database. Environmental impacts were calculated in OpenLCA (version 1.11) using the EPD (2018) method, considering global warming potential (GWP), acidification potential (ACP) and eutrophication potential (EUP). The results highlight that feed supply and the number of co-products considered are notable issues that influence environmental performance and assessment. The contribution analysis indicated that purchased feed was an important contributor to GWP and EUP, whereas emissions associated with manure management contributed substantially to ACP and EUP of the farm.