Effect of temperature on performance of qualitative tests for detection of common adulterants and preservatives in milk

摘要

Effect of milk temperature on the performance of the tests for detection of adulterants was evaluated at four different temperatures. Urease test for urea showed 40°C as optimum temperature for distinguishing control from spiked samples. Nessler's test for ammonium salts, methylene blue test for detergents and p-phenylenediamine test for hydrogen peroxide gave best results at 20 °C, while, Hehner's test for formaldehyde gave best results at 30°C. However, no effect of milk temperature was observedon p-dimethyl aminobenzaldehyde (DMAB) test for detection of urea, iodine test for detection of maltodextrin and rosolic acid test for detection of neutralizers.