Abstract:The visceral fat of Tibetan sheep fat was used as the raw material. Tibetan sheep fat was prepared by five different extraction methods, i.e. dry simmering, wet simmering, water enzymatic method, ultrasonic-assisted enzymatic hydrolysis and Soxhlet extraction. The effects of the five extraction methods on the quality of Tibetan sheep fat were investigated by taking the physicochemical properties, fatty acid composition and oxidative stability as the indexes. The results showed that the peroxide value of the Tibetan sheep fat extracted by the ultrasonic enzyme-assisted method was the lowest (0.02 g/100 g), and the saponification value was the highest (227.08 mg/g); the oxidative stability of the Tibetan sheep fat obtained by the ultrasonic-assisted enzyme hydrolysis method was superior to that of the Tibetan sheep fat extracted by the other four methods; the results of fatty acid analysis showed that a total of 36 fatty acids were detected in the Tibetan sheep fats obtained by the five different extraction methods , among which stearic acid (34.75%), palmitic acid (34.03%), and oleic acid (63.88%) were the fatty acids with the highest content percentages in the Tibetan sheep fats prepared by the five different extraction methods. Among the fat-soluble vitamins, the content of VA was the highest in the five types of Tibetan sheep fats, with an average content as high as (131 389±17 903.49) ng/g, and the contents of VE were higher (P<0.05) in the Tibetan sheep fats obtained by the dry simmering (5 079.79 ng/g) and ultrasound-assisted enzymatic hydrolysis (4 911.25 ng/g) methods. Based on the comprehensive comparison, the ultrasound-assisted enzymatic hydrolysis method led to a Tibetan sheep fat product with a higher yield and the best fat quality, which laid a theoretical foundation for the development and utilization of Tibetan sheep fat.
