Food traceability is becoming increasingly necessary in order to fight food fraud. Newly developed analytical techniques can detect both known and unknown contaminants and are essential for monitoring food safety.
by Prof. Reiner Wittkowski

The globalisation of the world’s food supply has brought about new challenges in food safety. While the inherent benefits of globalisation include a larger market for producers as well as greater variety and lower prices for consumers, the move towards a global supply model has inevitably brought about increased risks of widely distributed food contamination crises. Recent incidents such as dioxins found in Irish pork and melamine found in infant milk formula in China both highlight how globalisation has opened the possibilities for food contamination on a much larger scale. Naturally, the goal of every nation is a food supply that is safefor consumption consumed by its population; the food industry reflects this goal in its quest to bring safe foods to the market.

Food safety
Regulation (EC) No. 178/2002, article 14, of the European Parliament defines food safety as folows: “a food shall not be placed on the market if it is unsafe, and it is deemed to be unsafe if it is considered to be injurious to health or unfit for human consumption. Determining if a food product is safe requires the determination of probable effects on human health (by short- or long-term exposure) and the possible cumulative toxic effects, as well as identifying population groups with special sensitivities”.
While this sounds fairly obvious and relatively straightforward, it is important to understand that the safety of our food begins with the basic materials used for growing crops and raising food animals. In essence, overall food safety is affected not only by the raw ingredients but also by the technology, hygiene practices and packaging used in the production process. At the level of the final product, it is not necessarily clear which processes have been used in its production.

Challenges
One of the big challenges in the food industry is its dynamic nature: thus, new technologies can result in newpackaging materials and processes that could affect food safety. Because of the constant introduction of new substances, additives and technical innovations there is always the danger that new products and processes can give rise to a risk of previously unknown contaminants and food fraud In addition to all this, there are also predictable trends such as climate change, population increases and other demographic trends, as well as evolving energy policies that all affect food producers and suppliers.
 
One major issue is the false or erroneous description of food. In simple terms, “misdescription” means that the label on the food does not satisfy the legal requirements for describing the particular food. This is typically the case when manufacturers substitute cheaper, but similar, ingredients in their production processes. Sometimes this practice may involve increasing the amount of a food using an adulterant such as water or starch, or it may be an undeclared process such as irradiation or freezing. Misdescription of food may also involve specifying an incorrect origin (be it geographic, species of origin or method of production) or incorrectly specifying the quantitative amount of a particular ingredient.
From a regulatory standpoint, it is necessary not only to define the product and to develop standards and legal policies but also to determine ways of identifying and labelling food using appropriate terminology. Analytical control testing of food imports and exports, however, usually consists of a targetted analysis that focusses  on specific target analytes

Solutions
In order to fight food fraud, regulatory agencies are increasingly insisting upon total traceability, which is the ability to verify the history, location or application of a particular product by means of complete documentation and records.
Consequences of the availability of complete traceability of food products are that food crises can be avoided, rapid reactions can be initiated in the case of a crisis and regional markets and products can be protected and fair trade rules can be guaranteed. Through their use of traceability systems, regulatory agencies can thus verify geographic, production and species origin.

Traceability involves the documentation of the methods used in the analysis of the food, including classical analysis, wet chemistry, chromatography, spectroscopy and other techniques. Such methods can for example be used to detect non-natural food components through the analysis of stable isotopes and chemical elements. As shown in Figure 1, identifying the composition of a food can establish its authenticity, and verify its geographical origin and correct labelling. It can also reveal the presence of illegal additives or other adulterating substances.

It is more scientifically challenging to identify unknown components. The recent scandal of melamine-contaminated milk, highlighted the importance of the detection of abnormalities by fingerprinting profiling techniques [Figure 2]. Melamine in milk products had not been identified previously, simply because no control laboratory was acftually analysing for it. However, if, for example, screening using nuclear magnetic resource (NMR) spectroscopy had been carried out, non-compliance with the normal constituents of milk would have been easily detected. Fast screening techniques such as Fourier transform infrared spectroscopy (FT-IR) or high-resolution mass spectrometry coupled with liquid chromatography (LC/MS) can be used for non-targeted analysis of food. Such techniques require very little or no sample preparation; they can not only detect known adulterants, but they can also detect unknown adulterants that typically create new signals in the spectrum
being measured.

Conclusion
Newly developed analytical techniques, particularly those that have the advantage of universal detection, have been shown to be suitbable for the detection of both known and unknown components, which is a key element in monitoring the food supply and excluding contaminants from the food chain. Non-targeted analysis techniques, such as fingerprinting and profiling approaches, will become essential as screening tools in food control and safety assessment in order to highlight abnormalities. The industry’s efforts to correctly identify foodstuffs can help contain costly and life-threatening food contamination crises.

The author
Prof. Reiner Wittkowski,
Vice President,
Federal Institute for Risk Assessment (bfr),
Thielallee 88, Berlin, Germany
Fax: +49-30-18412-4970