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Addressing Food Authenticity Challenges
Analytical methods are critical for reliable food authentication
by Gerry Broski
Consumers around the world are increasingly demanding information on and reassurance of the origin and content of their food. In addition, food manufacturers must provide and confirm the authenticity and point of origin of food products and their components. These increased demands come amid legislative and regulatory pushes that increase the complexity and level of regulation imposed on the food supply worldwide. Protecting consumer rights and preventing fraudulent or deceptive practices such as food adulteration are important and challenging issues facing the food industry.
Food adulteration reports are a growing challenge for food manufacturers. Because most adulterants are unknown, they are difficult to recognize using the targeted screening methods typically used in food laboratories. The industry urgently needs methods that will screen non-targeted food samples for contaminants to provide proof of origin and prevent deliberate or accidental undeclared admixture to food samples.
Determining the authenticity of foods can prevent false description, substitution of cheaper ingredients, and adulteration, as well as incorrect origin labeling. This article will provide an overview of food authentication challenges and will highlight the need for rapid development of analytical methods to enable reliable food authentication.
Food Authentication Challenges
Consumers and producers alike place a high value on accurate and defensible labeling, and providers are now proactively providing consumers with clear labeling, traceability, and transparency. These producers must convert ingredients received from around the world into a finished product that is then distributed globally. The challenge for food producers lies in complying with international, national, and local traceability rules that apply both to what comes in and what goes out.
The growing variety and complexity of available foods is one challenge within the food industry. Consumers demand information about, and proof of, the quality and safety of “new” food items and preservatives. Meanwhile, rapid population growth results in raw material shortages, which in turn forces some producers to bulk up their products with questionable fillers, a strategy that, in itself, introduces additional ingredients of unknown origin.
Regulators worldwide must develop standards and legal policies to determine ways to identify and label food using appropriate terminology. Regulatory agencies now require food testing laboratories to meet lower detection levels for potential contaminants and continually add compounds and matrices to those that must be analyzed. Keeping contaminants out of the food chain requires robust instrumentation that can meet today’s threats while being advanced enough to address tomorrow’s challenges.
In 1979, European controls on food labeling were introduced with the European Parliament’s Directive 79/112/EEC. 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 Directive 2000/13/EC of the European Parliament and of the Council of 20 March 2000, which focuses on preventing fraudulent or deceptive practices and food adulteration.1
Directive 2000/13/EC requires detailed food labeling that includes the exact nature and characteristics of a product, enabling an informed consumer choice. It also requires that the ingredients list include the specific names of all raw materials in descending order by weight.
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 and specialty foods. These laws, enforced within the European Union, ensure that only those products genuinely originating in that region can be sold as such, eliminating unfair competition and misleading products that may be of inferior quality or made of different components.
Reliable analytical tools must be available along the food chain to verify the nature of food. Typically, several factors drive technique selection, including method detection limits, sample preparation, cost, and throughput. Such tools should permit rapid, nondestructive, and inexpensive analysis. The various techniques available for testing food authenticity include ultraviolet, near infrared, mid-infrared, and Raman spectroscopy methods. All of these are routinely used to control both raw materials and finished food products for specific production standards.
When monitoring for multiple chemical food contaminants, it is common to test various matrices that require multiple sample preparation techniques. The costs of purchasing and running the analytical instruments, as well as the specificity of the measurements, are among the issues that must be addressed.
Food safety analysts are also turning to mass spectrometry instruments and software to run multi-residue analytical methods. Stable isotope ratio mass spectrometry (SIRMS) is most often used to assess sample origin. SIRMS looks for changes in the characteristic isotopic profiles of stable isotopes of common elements such as hydrogen, oxygen, carbon, or nitrogen. The method provides high quality selectivity and achieves very low detection limits even in complex food samples.
Chromatography is used more often in food science and technology now because of its high separation capacity, and chromatographic techniques exist for rapid, reliable molecule separation with extremely similar chemical characteristics even in complex matrices. Gas chromatography is used most frequently for the quantitative analysis of numerous molecules such as normal constituents of foods, legal or illegal additives, and pollutants.
There is, however, room for development, especially in accelerating data evaluation of large food sample batches screened for hundreds of compounds. The development and evaluation of software tools that enable screening for the presence of unknown contaminants is crucial for easy identification and confirmation. The complexity of food samples complicates this process. 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.
Adulterated food has serious health ramifications for consumers, and chemical contamination can originate anywhere along the global food chain. Development efforts have sought to detect and quantify contamination in food samples, with special consideration for the most accurate and reliable analytical instrumentation that can rapidly test samples and safeguard the food supply.
Food authenticity testing encompasses multiple approaches and techniques that are constantly evolving to meet emerging challenges. Tremendous progress in establishing and proving food authenticity has been made. Chromatography and spectroscopy in their various formats, stable isotope ratio analysis, and immunochemical methods are widely used in food authentication. Increased reliance on these and other techniques will expand food testing professionals’ ability to address the current and emerging challenges in all aspects of food authentication.
- European Commission. Directive 2000/13/EC of the European Parliament and of the Council. Available at http://eur-lex.europa.eu/pri/ en/oj/dat/2000/l_109/l_10920000506en00290042.pdf . Accessed August 16, 2010.