Milk adulteration remains an endemic problem in many regions of the world. Police action, consumer illness and even fatalities are reported regularly from countries such as India and Pakistan. There is a need for simple, low-tech, cheap, tests that can be used by either business customers or by the public.
This paper (purchase required) describes a low-cost hybrid paper/plastic strip test for the simultaneous detection of seven potential adulterants in cow milk: urea, hydrogen peroxide, starch, formaldehyde, antioxidants, sodium hypochlorite, and neutralisers/detergent. It uses pH-based colorimetric sensing without sample pretreatment. The device was fabricated using a craft cutter and combined paper and plastic substrates, allowing multiplexed detection on a single strip.
The authors report that the test strips remained stable for up to 30 days under refrigeration (2–5 °C). In a case study of 50 milk samples, the device accurately identified adulterants with minimal interference, and results showed no significant deviation from reference methods.
Fabrication costs are around $0.25 per unit. The authors conclude that the proposed platform provides a reliable, affordable, and scalable solution for routine milk quality monitoring, representing a promising tool for enhancing quality control in the dairy industry.
[image from the publication]
