In cooperation with the Sardinian Regional Breeders Association (ARA Sardegna), a total of 250 sheep milk samples was collected from several breeding farms in Northern, Central and Southern areas of Sardinia, covering a period of time ranging from January 2011 to April 2013. In this way it was possible to gather up samples that included variability due to different factors such as geographical areas, season, different herd management and feeding system. In particular, 118 individual sheep milk samples were collected weekly from a sheep breed reared at the experimental farm of AGRIS Sardegna (Northern Sardinia) from January to May 2011, 26 individual samples were collected from the same breed in March and April 2013, 60 bulk sheep milk samples were collected from sheep breeding farms in the central area of Sardinia from February to April 2012, 20 bulk milk samples were collected in the central area of Sardinia in November 2012 and 26 bulk milk samples were collected from as many breeding farms in the Southern area of Sardinia from May to June 2012. All samples were divided into two homogeneous sub-samples and stored at 4 °C. Whereas an aliquot was used to acquire MIR spectrum, the other one was destined to fatty acid analysis and processed to separate milk fat cream within 4 h.