Barbaresca sheep milk: lipid and mineral composition under the influence of grazing in the Nebrodi mountains

Francesca Aragona; Vincenzo Nava; Angela Giorgia Potortí; Federica Litrenta; Antonino Costa; Francesco Fazio; Vincenzo Lo Turco

Francesca Aragona Department of Veterinary Science, University of Messina, 98168 Messina, Italy
Vincenzo Nava Department of Biomedical and Dental Sciences and of Morphological and Functional Images, University of Messina, 98168 Messina, Italy
Angela Giorgia Potortí Department of Biomedical and Dental Sciences and of Morphological and Functional Images, University of Messina, 98168 Messina, Italy
Federica Litrenta Department of Chemical, Biological, Pharmaceutical, and Environmental Sciences, 98168 Messina, Italy
Antonino Costa Department of Veterinary Science, University of Messina, 98168 Messina, Italy
Francesco Fazio Department of Veterinary Science, University of Messina, 98168 Messina, Italy
Vincenzo Lo Turco Department of Biomedical and Dental Sciences and of Morphological and Functional Images, University of Messina, 98168 Messina, Italy

Keywords: Barbaresca sheep milk; Essential minerals elements; Toxic elements; Fatty acid profile; Nutritional value

Abstract

Sheep milk is a crucial food source in many Mediterranean cultures and is a significant economic resource in the hilly and mountainous regions of Sicily. This study evaluated the milk composition of Barbaresca sheep, an indigenous Sicilian breed considered at high risk of extinction, known for its rusticity and adaptability to harsh environments. This research specifically focuses on the fatty acid profile and the presence of essential and toxic mineral elements, linking these characteristics to the Nebrodi pasture where the sheep graze. The experimental design involved collecting milk samples from Barbaresca sheep on a family-run farm located in a non-industrialized region of Sicily surrounded by the Nebrodi mountains. The sheep were managed under a semi-extensive farming system, grazing freely on pastures characterized by diverse flora, including Graminaceae, Asteraceae, Leguminosae, and various tree species like olive and chestnut. The collected milk samples were analyzed for mineral elements using ICP-MS and DMA for mercury, and for fatty acid composition using GC-FID. The main findings highlight the high content of essential minerals in Barbaresca sheep milk. Specifically, it significantly contributes to the recommended daily intake of essential minerals such as calcium and zinc. Other macroelements like potassium, sodium, and magnesium were also found in high concentrations. Essential trace elements like iron, manganese, copper, chromium, and molybdenum were also detected. The study also found limited health risk from toxic elements due to grazing in an environment far from sources of pollution. The milk has a rich and complex lipid profile, with a significant content of beneficial fatty acids such as linoleic and linolenic acids, and a balance between omega-6 and omega-3. The presence of short-chain fatty acids (SCFA) contributes to the typical flavor of the milk and its products. The lipid quality indices were favorable for a product of animal origin and suggest potential positive effects on cardiovascular health. This beneficial fatty acid composition is likely influenced by the inclusion of pasture in the sheep diet, particularly the diverse endemic vegetation of the Nebrodi Mountains.

In conclusion, the milk of the Barbaresca sheep can be considered safe and healthy due to the grazing in the varied vegetation endemic to the Nebrodi Mountains. This study contributes to the valorization of Barbaresca sheep milk as a high-quality product linked to the Nebrodi territory, promoting the sustainability of the grazing system and local biodiversity.