Ensuring Food Authenticity and Quality

Protection of consumer rights, the prevention of fraudulent or deceptive practices, and the adulteration of food are important challenging issues facing the food industry.  Consumers today are becoming increasingly interested in information regarding the origin of their food. Regulators are also demanding that food manufacturers confirm the authenticity and  point of origin of their products and components. As a result,  more stringent legislation reflecting these demands is now being imposed upon the global food supply.

Verifying the authenticity of foods can prevent false description, substitution with cheaper ingredients, adulteration, and incorrect origin labeling. Food manufacturers are increasingly aware of and are affected by reports of food adulteration. Some adulterants are unknown and, as such, are difficult to recognize using the targeted screening methods typically used in food laboratories. Therefore, methods and solutions for nontargeted screening of food samples are urgently needed to provide proof of origin and prevent deliberate or accidental, undeclared admixture of foods. This article provides an overview of food authentication challenges and highlights the need for rapid development of analytical methods to enable reliable authentication of food.

Food authentication challenges

Consumers and producers place a high value on accurate and defensible labeling. As a result, manufacturers are taking proactive steps to provide consumers with clear labeling, traceability, and transparency. In doing so, producers must manage a supply chain in which they source ingredients from around the world and convert them into a finished product that is then distributed globally. Food producers, therefore, not only face the challenge of complying with international, national, and local traceability rules, but the challenge of maintaining responsibility for the authenticity of ingredients.

The growing variety and complexity of available foods also poses a challenge within the food industry. Consumers are demanding information about and proof of the quality and safety of “new” food items and preservatives that prevent deterioration. Meanwhile, rapid population growth has resulted in shortages of raw materials, which in turn has forced some producers to “bulk up” their products with questionable fillers, thus introducing additional ingredients of unknown origin.

Regulatory framework

Regulators around the world have been tasked with developing standards and legal policies to determine ways to identify and label food using appropriate terminology. Regulatory agencies now require food testing laboratories to meet higher standards of detection and analysis. They are also requiring laboratories to have the capacity to detect extremely low concentrations of potential contaminants. In addition, new and unknown compounds and matrices are continually being added to food, necessitating the requirement for both targeted and nontargeted analysis. In order to prevent excessive levels of contaminants from entering the food chain, but it is also vital that food laboratories are equipped with robust instrumentation that can meet not only today’s threats but that is also advanced enough to address tomorrow’s challenges.

European controls on food labeling were introduced with Directive 79/112 of the European Parliament in 1979, and additional controls and amendments have since been added, creating an array of labeling requirements. In 2000, the original 1979 directive and its amendments were consolidated into a single new directive, The Council Directive 2000/13/EC of The European Parliament and of the Council of 20 March 2001,1 which focuses on preventing fraudulent or deceptive practices and adulteration of food that may mislead consumers.

Directive 2000/13/EC requires detailed food labeling to include the exact nature and characteristics of a product, enabling an informed consumer choice. It also requires that the ingredients list include all raw materials in descending order by weight, using their specific name.

European law also provides labeling for protected designation of origin (PDO), protected geographical indication (PGI), and traditional specialty guaranteed (TSG) to ensure the authenticity of regional foods and specialties. These laws, enforced within the EU, ensure that only products genuinely originating in that region are allowed to be sold as such, eliminating unfair competition and misleading products that may be of inferior quality or of different components.

Techniques

Figure 1 - Techniques used to test food authenticity.

Table 1  -  Food authenticity testing techniques

Reliable analytical tools must be available along the food chain to verify the nature of food. Typically, the selection of techniques is driven by several factors, including method detection limits, sample preparation, cost, and throughput. Such tools should permit rapid, nondestructive, and inexpensive analysis. There are a variety of techniques to test food authenticity, including methods based on ultraviolet (UV), near-infrared (NIR), midinfrared (MIR), and Raman spectroscopy (see Figure 1 and Table 1). All of these are routinely used to control both raw materials and finished food products for specific production standards.

When monitoring for multiple chemical contaminants in food, it is common to test a variety of matrices that require multiple sample preparation techniques. Issues must be addressed, however, including the costs of purchasing and running the analytical instruments as well as the specificity of the measurements.

Food safety analysts are also turning to mass spectrometry instruments and software to run multiresidue analytical methods. Stable isotope ratio mass spectrometry (SIRMS) is most often used to assess sample origin by looking for the changes in the characteristic isotopic profiles of stable isotopes of common elements such as hydrogen, oxygen, carbon, and nitrogen. SIRMS provides high-quality selectivity and achieves very low detection limits, even in complex food samples.

Chromatography is being increasingly employed in food science and technology because of its high separation capacity. Chromatographic techniques exist for rapid, reliable separation of molecules with extremely similar chemical characteristics even in complex matrices. Gas chromatography is most frequently used for the quantitative analysis of numerous molecules such as normal constituents of foods, legal or illegal additives, and pollutants.

There is room for development in the area of evaluation and processing to speed data analysis of large food sample batches screened for hundreds of compounds. The development and evaluation of software tools that permit screening for the presence of unknown contaminants is crucial for easy identification and confirmation. This process is complicated, however, due to the complexity of food samples. Since a typical food extract can contain thousands of compounds in a broad range of concentrations, software tools must differentiate between “normal” and contaminated samples, even at low concentration.