New test to detect detergents in milk developed

Though there is no official figures on how big is the problem of presence of detergents in milk, unofficial estimates show that almost 50%of total milk produced in India has shown the presence of harm

The state-run National Dairy Research Institute (NDRI) in Karnal has developed a new test to detect the presence of harmful detergents in milk.

The test, which can be performed by just mixing a chemical in a small sample of milk, has been sold commercially to Mother Dairy, whose officials said they would soon sell it in the market in the form of a kit.

According to NDRI director A K Srivastava, the test is colour-based and the results are available just after the mixing of reagents and milk sample. If the lower layer turns blue, there are detergents in the milk. But if the milk is pure, the lower layer would be pink.

“The method does not require the use of any instrument and is sensitive enough to detect the presence of up to 20 mg laboratory grade detergent in 100 ml of milk, implying that even two litres of synthetic milk added to 100 litres of milk could be easily detected,” Srivastava told Business Standard. A patent application too has been filed for the test.

But he warned that as the test involved the usage of harmful chemicals, it was not advisable for houesholds to conduct such a test on their milk sample. Large aggrerators of milk like the dairy industry or even big hotels, though, could use this simple test to ascertain the presence of detergents in milk.

Though there are no official figures on how big the problem of presence of detergents in milk is, unofficial estimates show that almost 50 per cent of the total milk produced in India has shown the presence of harmful detergents.

India annually produces over 125 million litres of milk. The detergents are added both, during primary extraction of milk and also during secondary processing. Srivastava said that more than 700 dairy plants across the country and 15 state cooperative societies could benefit from this simple chemical test.

“The cost of testing per sample is around Rs. 1.60. The test could detect all brands of commercial detergents available in the market,” he said, adding that there was no other rapid test to detect detergents available in the market at present.

“The test requires just 400 microlitres of milk sample,” Srivastava said. That's not all, NDRI is also working on a simpler test for detection of other common adulterants in milk. These tests are strip/paper type and based on the concept of "dry chemistry" and might be used at the house-hold level as well.