CEERI’s cost-effective handheld tester can help dairy businesses stay more informed about the milk they provide
Under-test prototype of the milk fat tester
Food adulteration is a serious problem in the food processing industry today. Adulteration involves the introduction of chemical substances to food and beverages to improve their appearance or volume, and increase sales appeal. These chemicals are often hazardous to health, detrimental to food quality and can lead to severe complications for consumers.
Moreover, distributed food products that remain unevaluated for adulteration before reaching buyers lead to health complications. This directly affects brand reputation and, eventually, business of the food manufacturer. To help food business owners as well as consumers be cautious about the quality of the food being sold, CSIR-CEERI has developed a technology that acts as an electronic tongue.
Challenges in dairy adulteration
Milk adulteration has been one of the most prevalent nuisances in the food industry. At the time, chemical tests were the popular choice when it came to adulteration detection. Popular milk adulterants in India include urea, salt, detergent, caustic soda, ammonium sulphate, boric acid and hydrogen peroxide, among others.
Chemical test processes are time-, resource- and effort-heavy, as a specific adulterant can be detected with a specific reaction only. A single reaction takes at least four to five minutes to generate a post-reaction colour. Users have to conduct multiple tests to find out the right adulterant.
Outcomes of the tests are also difficult to pinpoint as colour changes are often hard to distinguish. There is also an environmental constraint when using chemicals.
In the market, a strip test facility is also available, which changes colour if dipped in adulterated milk for about five minutes. However, the strips are expensive and not practical for real-life situations, like in rural areas where there are long queues for milk collection, or in households where packaged milk is directly used.
Later, electronic devices were imported for dairy testing. But these had a big form factor, and each unit’s cost was ₹ 10 million or above, with maintenance costs of ₹ 5000 to ₹ 10,000 every three to four months. Sensors malfunctioned due to lack of cleaning. Looking at all these constraints, CEERI got to work to find a compact and cost-effective alternative.
Benefits of the portable tester
In an initial project of developing automated tea quality test technology, the team at CEERI designed a system mimicking a human being testing tea—through colour, smell and taste. Starting from that project, the team developed a system using a computer vision-enabled camera for colour identification, an electronic nose for odour identification and, finally, an electronic tongue to test taste. The design prompted the application of these technologies further into milk and other beverages like tea, juice and wine.
The system works on a simple electrochemical principle. A metal alloy electrode, when dipped in a liquid, measures the electrochemical signature of the sample. Pure milk has an electrochemical signature that changes with the introduction of adulterants. The electrode detects if there is a change in the electrochemical signature due to reaction by ions of the adulterant.
This allowes users to know if the milk is adulterated. The system can be Wi-Fi-enabled with cloud connectivity, to store data remotely. It may also be connected to a smartphone through cables. A 9V lithium-ion battery powers the system.
This technology can be highly beneficial for dairy businesses to ensure quality of milk they are selling. Usually, milk is procured from a collection centre and is sent to a chilling centre for preservation at proper temperature. From there, it reaches the dairy outlet in the market.
Having a device at all locations can help businesses stay informed about the quantity, quality and preservation of milk at each stage. Whenever any deviation is noted at any location, remedial actions can be taken immediately. This way, outlet owners can stop adulterated milk from reaching the market.
Alternatively, the technology developed by CEERI is economical enough to be purchased by end consumers, who can test a sample of the milk they purchase before consumption.
Commercial use
The team at CEERI estimates that the bill of material of the technology will be around ₹ 5000. So far, it has collaborated with Rajasthan Electronics Instruments in Jaipur and some other product developers, whom they are transferring the technology to, for manufacturing the product.
CEERI provides one year of hand-holding, starting with providing design documents, hex files, programs, as well as guidance in terms of manufacturing, test and debugging of the first 25 products being manufactured, all without any charge.
CEERI researchers recall miniaturising the device, formulating the circuit design, component selection and fitting the program in an 8-bit controller as challenging tasks.
The system, once commercialised, has the potential to save consumers from adulterated dairy-driven health issues. At the same time, it can enable dairy providers to be more cautious about their product quality, thus saving their market reputation, as well as major expenses from wastage by enabling quick root-cause analysis.
