Eyebrows were raised in September when a member of the Animal Welfare Board disclosed that over 68 per cent of milk and milk products sold in the country don't meet the standards laid down by the Food Safety and Standards Authority of India (FSSAI). Here's more bad news: According to the World Health Organisation (WHO), if such adulteration is not checked immediately, 87 per cent of citizens would be suffering from serious diseases like cancer by 2025.
Thankfully, researchers from Indian Institute of Technology (IIT) Hyderabad seem to have found a way to help you detect adulteration using your smartphone. The research, undertaken by a team led by Professor Shiv Govind Singh, department of electrical engineering, has been published in the November 2018 issue of Food Analytical Methods journal.
So how does the new system work? As a first step, the team behind the project have developed a detector system to measure the acidity of milk through an indicator paper that changes colour depending on the level. The researchers have also developed algorithms that can be incorporated into a mobile phone to accurately detect the colour change. On testing with milk spiked with various combinations of contaminants, the team found near-perfect classification with accuracy of 99.71 per cent.
"While techniques such as chromatography and spectroscopy can be used to detect adulteration, such techniques generally require expensive setup and are not amenable to miniaturisation into low-cost easy-to-use devices. Hence, they do not appeal to the vast majority of milk consumers in the developing world," Singh said in a statement. "It should be possible to make milk adulteration detection failsafe by monitoring all of these parameters at the same time, without the need for expensive equipment."
The research team, comprising associate professors Soumya Jana and Siva Rama Krishna Vanjari, used a process called 'electrospinning' to produce paper-like material made of nano-sized (~10-9 m diameter) fibres of nylon, The Times of India reported. The material, loaded with a combination of three dyes, is "halochromic". That means that it changes colour in response to changes in acidity.
In other words, the prototype smartphone-based algorithm analyses the colour of the sensor strips that are dipped in milk and then captured using the phone's camera. This data is then converted into pH (acidity) ranges. The team reportedly used three machine-learning algorithms and compared their detection efficiencies in classifying the colour of the indicator strips.
Singh and his team are now looking to extend the research to study the effects of mobile phone cameras and lighting on detection efficiency. In the long run, the researchers hope to develop sensors for other physical properties such as conductivity and refractive index, and integrate it with the pH detection unit to obtain comprehensive milk quality check systems that can be easily deployed by consumers.
With PTI inputs
(Edited by Sushmita Choudhury Agarwal)