Detection of milk fat adulteration with admixture of foreign oils and fats using a fractionation technique and the apparent solidification time test

Abstract

A fractionation technique followed by the apparent solidification time (AST) test was adopted for detecting the admixture of foreign oils and fats in milk fat. The AST values of the solid fraction obtained at 20°C, and solid and liquid fractions obtained at 18°C for pure cow milk fat, were 2 min 30 s, and 3 min 21 s and 3 min 31 s, while for buffalo milk fat they were 1 min 58 s, and 2 min 47 s and 3 min 10 s respectively. This new approach can detect some mixtures of foreign oils and fats in cow milk fat but not in buffalo milk fat.

Complete liquification time test coupled with solvent fractionation technique to detect adulteration of foreign fats in ghee

“…Kumar et al . (, ) also developed a test recently based on the physical property of milk fat, namely the AST test at 18 °C in which the apparent solidification behaviour in terms of the time taken at a given temperature for the melted fat to appear solid is noted. This study used a 1:1 ratio of goat body fat and vegetable oil as adulterant.…”

“…Moreover, the opacity test suffers from another drawback in that it fails to detect the animal body fats in ghee in the presence of vegetable oils. Kumar et al (2009Kumar et al ( , 2010 also developed a test recently based on the physical property of milk fat, namely the AST test at 18°C in which the apparent solidification behaviour in terms of the time taken at a given temperature for the melted fat to appear solid is noted. This study used a 1:1 ratio of goat body fat and vegetable oil as adulterant.…”

“…In the past, tests based on the partial solidification behaviour of milk fat such as an opacity test (Singhal ; Sharma and Singhal ; Panda and Bindal ), or the apparent solidification time (AST) test (Kumar et al . , ) have been employed as criteria for detecting adulteration in ghee with animal body fat. However, limited information is available on the liquification behaviour of milk fat (Kumar , ).…”

“…Short-chain fatty acids and unsaturated fatty acids can decrease the time required for liquifying the presolidified fat, while the reverse will be true for long-chain saturated fatty acids. In the past, tests based on the partial solidification behaviour of milk fat such as an opacity test (Singhal 1980;Sharma and Singhal 1996;Panda and Bindal 1998), or the apparent solidification time (AST) test (Kumar et al 2009(Kumar et al , 2010 have been employed as criteria for detecting adulteration in ghee with animal body fat. However, limited information is available on the liquification behaviour of milk fat (Kumar 2008(Kumar , 2013.…”

Development of a method employing reversed‐phase thin‐layer chromatography for establishing milk fat purity with respect to adulteration with vegetable oils

“…Milk fat is an important food component and plays a significant role in the economics, nutrition and physical and chemical properties of milk and milk-derived products; it is a good source of fat-soluble vitamins and essential fatty acids (Kumar et al 2010). Nutritional aspects of milk fat (ghee) have gained increasing importance, in particular short chain saturated, polyunsaturated and conjugated fatty acids, which are potentially identified as positive predisposing factors for human health (Wolff 1995;Williams 2000).…”