FOOD & DRINK TECHNOLOGY 93
or production method, and check for food quality in general. But these profiling tools come with the ability to drill down into the data to identify the chemical substance(s) that cause any deviation from normality. And a pre-requisite is also to know what constitutes a ‘normal’ sample. Tis can reveal information on the detailed chemical composition of food and feed that was hitherto unknown – and we need to be prepared for the unexpected.
Te issue of detection limits has been faced already. As the analytical sensitivity increases, the default position of zero tolerance – ‘should not be detected at the detection limit of the analytical method’ – becomes untenable for prohibited additives, contaminants and residues of food production chemicals. If we can (now, or in the future) detect ‘just a few molecules’ then we will detect everything in everything – rather simplistically, all chemicals in all samples. In the majority of cases, the presence of a few parts- per-billion or parts-per-trillion of a chemical would present no real concerns with regards to adulteration or consumer safety, and so a non-zero threshold limit must be accepted for pragmatic reasons.
Similarly, in terms of analytical coverage, we will surely find that even normal food samples contain chemicals that we do not yet know about. Te best recent example is acrylamide. Acrylamide may be a ‘normal’ product of some cooking processes, but nonetheless being normal – and therefore present in all of the affected food types – is not (and was not) a cause or even an excuse for complacency and inaction. Another example could be as-yet unknown bioactive substances present in plant products such as fruits, vegetables, herbs and spices. Some may be beneficial,
“We do need to lift the stone and look under, or open Pandora’s box (to mix metaphors) but we also need to be prepared to interpret, understand and act upon what is found.”
some may be detrimental. Some may be both, depending on the intake, since ‘the dose makes the poison’. As we apply profiling techniques more widely, we will indeed find more and more of less and less. So many analytical chemistry instruments, such as LC-MS, GC-MS and NMR, will give ‘straight out of the box’ data and information on a sample. But we can agree with Stoll: ‘Data is not information, Information is not knowledge, Knowledge is not understanding’.
Te findings from the analytical lab must eventually lead to risk management or quality management decisions, and vice-versa. Such decisions should initiate and guide the analytical work to be conducted. For the consideration of food safety and risk, analytical thresholds can be entirely consistent with modern risk assessment principles, such as thresholds of toxicological concern.
For quality management decisions, it is a contract between the supplier and the customer. An agreement from both sides is required, as to what exactly constitutes the principle that food should be of the nature and quality expected by the consumer. It should be safe, wholesome, nutritious and authentic – not subject to adulteration and fraud.
When does ‘a few molecules’, a practically zero but not actually zero concentration, become unacceptable? We do need to lift the stone and look under, or open Pandora’s box (to mix metaphors) but we also need to be prepared to interpret, understand and act upon what is found. Tese are the opportunities – and particularly the challenges – offered by our advances in analytical chemistry.
Laurence Castle is a principal scientist at The Food and Environment Research Agency (Fera) in York, UK.
www.fera.defra.gov.uk
www.scientistlive.com
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