On a global scale, milk is the second most commonly adulterated food (after olive oil). The sources might be due to deliberate or accidental contamination in the dairy supply chain. For instance, in some developing areas of the world the criminal practice of adding substances to gain higher payment for milk deliveries is a constant threat. Meanwhile, accidental contamination, for example, from fluids used to clean storage equipment is a risk for even the most well-developed supply chain.
To help combat the problem, FOSS has released a new adulteration screening package for MilkoScan™ 7 RM and MilkoScan™ FT+ analysers which are widely used by milk testing centers around the world. The new capability makes perfect sense as a convenient and cost-effective way to check the integrity of milk samples from the dairy farm.
Practical solution exploiting existing infrared analytical technology
The screening test is based on a powerful form of infrared analysis called Fourier Transform Infrared (FTIR) already used in the MilkoScan™ 7 RM and MilkoScan™ FT+ analysers for multi-parameter tests. The adulteration screening is done using the infrared spectrum involved in the FTIR test. Spectra from a sample are compared against a so-called infrared ‘spectral fingerprint’ for normal milk programed into the instrument. In this way, a warning about general adulteration is given if a mismatch occurs. The milk spectra is checked further for similarities of spectral signatures against specific sources of adulteration and warnings are given in case of a match. All this occurs simultaneously in as little as 6 six seconds with the routine tests so that no additional time or sample handling is involved.
16 known food safety and quality threats can be identified from a single test
A screening test that identifies if something is wrong with a sample (untargeted adulteration screening) has been available for several years. The release of targeted-adulteration screening models allows known sources of milk adulteration to be identified as well. Accordingly, milk-testing centers can now screen for possible adulteration and use the targeted tests to zoom-in on specific sources. Examples include sodium hydroxide that can occur due to insufficient rinsing after cleaning of equipment or melamine added to increase the apparent protein content with the intention of gaining higher payment for milk deliveries.
Rationalising the use of resource-heavy methods
Another aspect of the screening tests is that they are far less time-consuming and expensive compared, for example, to chemical reference methods. They also use a tiny fraction of the consumables compared to reference methods. While these methods will remain the ultimate ‘go to’ reference, the screening approach can provide a valuable supplement that saves time and resources.
Because the screening can be performed repeatedly at no extra cost and as little as six seconds per test, it is quick to check whether a positive result is something random or something worth investigating further with a reference test. The identified source of contamination then helps to select the appropriate reference method to use for confirmation of the screening.
Simple to implement test with significant boost for laboratory service offerings
The tests are straightforward to implement in a few hours, for instance with adjustment to local climate, feeding and seasonal aspects affecting the characteristics of the raw milk samples which will be screened. This relatively small step then opens up a convenient way for laboratories to join in on the growing international focus on food safety.
Farmers can get vital information about unintended adulteration in production systems allowing them to improve quality and avoid financial penalties for sub-standard deliveries. Dairies can use the tests to ensure the quality of processed products while milk testing laboratories can extend their food safety testing services without having to invest in new test equipment.
Logical solution for protecting the global supply chain
The working lifetime of MilkoScan™ instruments is proven to be long with many units still in operation after ten years. With a testing capacity of up to 600 samples an hour, units can easily perform around 5000 tests per daily shift. Further, on a global level, the instruments are easily the most widely-used raw milk testing equipment with thousands of units in operation at milk-testing centers around the globe.
Given that the targeted screening can be effectively rolled-out across existing analytical equipment and that it is performed as part of normal testing routines with no extra resources or infrastructure involved, the screening is clearly a highly cost-effective option. In short, the new targeted adulteration models offer a straightforward and logical solution for protecting against accidental or deliberate adulteration of the raw milk supply chain.