五种不同方法提取的藏羊油脂品质比较

Comparison on the Quality of Tibetan Sheep Fat Extracted by Five Different Methods

摘要:

以藏羊油脂内脏脂肪为原料，通过五种不同提取方法，即干法熬制、湿法熬制、水酶法、超声波辅助酶解法和索氏抽提法制备得到藏羊油脂，并以其理化性质、脂肪酸组成和氧化稳定性等为指标，研究了五种提取方法对藏羊油脂品质的影响。结果表明：超声波酶辅助法提取藏羊油脂过氧化值最低，为0.02 g/100 g，皂化值最高为227.08 mg/g；超声辅助酶解法所得藏羊油脂的氧化稳定性优于其他四种方法提取的藏羊油脂；脂肪酸结果显示，五种不同提取方法对藏羊油脂中共检测到36种脂肪酸，其中，硬脂酸（34.75%）、棕榈酸（34.03%）、油酸（63.88%）是这五种不同提取方法藏羊油脂种含量占比最高的脂肪酸。脂溶性维生素中VA的含量在五种藏羊油脂种最高，平均高达（131 389±17 903.49）ng/g，VE含量在干法熬制（5 079.79 ng/g）和超声辅助酶解法（4 911.25 ng/g）所得藏羊油脂中较高（P<0.05）。综合比较，超声辅助酶解法提取藏羊油脂得率较高，油脂品质最佳，为藏羊油脂的开发与利用奠定了理论基础。

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.