Apparent solidification time test for detection of foreign oils and fats adulterated in clarified milk fat, as affected by season and storage

An apparent solidification time (AST) test was developed for the detection of foreign fats and oils in milk fat. AST values at 18°C for buffalo and cow milk fats ranged from 2 min 30 s to 2 min 48 s and 2 min 56 s to 3 min 26 s, while for pig body fat, goat body fat and hydrogenated vegetable oils, AST values were 1 min 30 s, 0 min 40 s and 1 min 50 s, respectively. Vegetable oils yielded no AST values, suggesting that adulteration can be detected using the AST method in the case of some but not all possible adulterants.