Research by the Global Good Fund into the emerging availability of very low-cost milk-adulteration detection systems for farms, dairies and governments in developing nations, has highlighted that mid-IR and Raman-IR spectroscopic devices “hold promise for use in low resource settings.”  Mid-IR and raman-IR were found to meet market sensitivity requirements and to offer “dramatically lower cost” with efforts underway to lower system prices below $2,000.  The paper re-iterates the well-known examples of chronic adulteration and of mass hospitalisations in specific cases.  Examples in India and China are quoted[1]. There are several established methods for identifying adulterants accurately enough, but “they are too expensive and/or lack field portability for use in low income countries”.  The advent of significantly lower cost devices will allow much more widespread control of this public health issue.

The Global Good Fund is part of Bill Gates’ and Nathan Myhrvold’s Intellectual Ventures, which seeks to develop and commercialise technology that transforms industries in the developed and developing world. Food security, including adulteration detection in food and feed, is a key area of the organisation’s research and innovation funding.

The research – published in the journal Proc. SPIE – highlights that adulteration of milk for economic gains is a widespread issue throughout the developing world with far-reaching health and nutritional impacts, citing ammonium sulfate, melamine, sodium bicarbonate, sucrose, and urea as the most common adulterants.

And while several milk analysis technologies can screen for adulteration, they are too expensive to use in low resource settings. The research identified two technologies with potential to provide lower cost analysis.  These were mid-IR spectroscopy and Raman techniques. Their effectiveness was assessed by evaluating performance in detecting and quantifying the presence of the five most common milk adulterants.

Collected MIR and Raman spectra were analysed and both systems achieved detection for each adulterant at target levels of sensitivity set by industry, with the limit of detection (LOD) for each adulterant determined to be in the range of 100 to 4000 ppm (0.01% – 0.4%).  MIR showed more even LODs across the adulterant classes.

The paper concludes that “overall, the LODs were comparable to other spectroscopic milk analyzers on the market, and they were within the economically relevant concentration range of 100 to 4000 ppm. These lower cost spectroscopic devices therefore appear to hold promise for use in low resource settings without complicated sample preparation and at a very low cost per test.”

Andrew Wallace, CEO of Pyreos, which manufactures mid-IR spectroscopy technologies welcomed the research and conclusions. “The research highlights the importance of low-cost detection systems. There is a significant economic benefit for counterfeiters, and this will only increase as climate change disrupts food production. As a result, there is a growing need for portable, low-cost analysers, such as those built by our customers that can quickly and easily detect a large range of contaminants for most food products. Pyreos sensors enable these analysers by being low cost, instant switch-on, low power and robust.  We’re delighted that such a key organisation recognises the need for these technologies and we will make further announcements in the near future demonstrating how Pyreos is driving accessibility of lower cost food testing worldwide.”

In a national survey on milk adulteration in 2011 by the Food Safety and Standards Authority of India, only 31.5 % of samples conformed to the standards. In some states, 100 % of the samples failed to meet the standards. When adulterated, the milk becomes not only inferior in nutrition, but could also be hazardous for consumers. Milk adulterated with melamine killed six infants and hospitalised over 50,000 others in China in 2008.