Caracterização do leite ovino em função do período de lactação

Abstract

Sheep milk is produced in Brazil mainly in the South and Southeast regions and, because it has a higher content of solids than cow milk, it is usually processed into dairy products, especially cheese and yogurt. In this sense, the reduced number of studies in the area, associated to the lack of scientific information related to dairy products from ovine culture, stimulated the creation of the present study that aims to evaluate the physicochemical composition and to determine and analyze the content of mineral elements and the profile of fatty acids of sheep milk, related to the period of lactation. Two treatments were used: treatment 1 with milk of ½ Laucane blood sheep and treatment 2 with milk of Ile de France x Texel crossbred sheep, which were milked from the 1st to the 10th week of lactation. The progress in the lactation period of ½ blood and crossbred sheep showed an increase in fat content, with 7.37 and 6.47% in the first week passing to 7.54 and 7.62% in the last week, respectively. The values of protein were 4.75% for ½ Laucane blood sheep and 4.97% for Ile de France x Texel crossbred sheep in the beginning of the lactation reaching the tenth week with values of 4.67 and 4.61%, respectively. There is a higher concentration of saturated fatty acids for the Ile de France x Texel crossbred sheep with values oscillating between 67.09 and 74.65%. Regarding the concentrations of mono and polyunsaturated fatty acids, a superiority for ½ Laucane blood sheep was observed, with values of monounsaturated fatty acids ranging from 22.50 to 28.50% and polyunsaturated from 4.52 to 5.20%. The mineral elements Ca, S, P, Mg, K and Na present in ovine milk did not show a pattern of variation during the evaluated lactation period for both genetic groups. The Ca content was higher for the milk of ½ Laucane blood sheep, demonstrating a variation between 131.63 and 218.49 mg/100 mL. The amount of P obtained in ovine milk was lower than that of Ca, where ½ Laucane blood sheep showed higher values, presenting the same behavior that the element Ca. The Na and K content was higher in the milk of ½ Laucane blood sheep, not differing significantly in the fourth and fifth weeks for the two genetic groups evaluated, in the same way that K did not differ in the third week of lactation either. Similar to the other minerals, S and Mg content was lower for Ile de France x Texel crossbred sheep.