The term ‘food provenance’, as outlined in Chapter 15, relates to not only the geographic elements of where the ingredients and the final food are grown processed and finally manufactured but also how that food is produced and whether the methods of production comply with certain standards and protocols. Authentic products are those that demonstrate a given connection to a recipe, location or social characteristic. Product integrity refers to the wholeness, completeness or soundness of a food product. This chapter considers the emerging testing procedures that are being used to test and verify either product integrity or provenance characteristics that are attributed to the product.
36.1 Authenticity is the innate quality of being authentic, genuine and of undisputed origin. Concerns with regard to food authenticity and the potential for substitution and adulteration in the food supply chain mean that increasingly food manufacturers are developing verification activities to determine the provenance and integrity of food. These tests are expensive and need to be completed using sophisticated and expensive equipment, but purchasing this equipment is often outside of the financial resources of many food manufacturers. The quality manager or designate, on behalf of the food manufacturer, needs to undertake a risk assessment to determine which foods are most at risk of food fraud (see Chapter 6) using approaches such as threat analysis critical control point (TACCP). The contract analysis laboratory, if used, must comply with established principles of good control laboratory practice (see Chapter 38). Verification schedules need to be developed, implemented and reviewed to ensure that they are effective. In the event of identification of non‐compliance, appropriate corrective action procedures need to be implemented and if necessary a product withdrawal or recall instigated.
36.2 Food authenticity testing uses a range of techniques, including gas chromatography (GC), ultraviolet (UV) spectroscopy, high‐performance liquid chromatography (HPLC), liquid chromatography, nuclear magnetic resonance (NMR), mass spectrometry (MS), deoxyribonucleic acid (DNA) fingerprinting and infrared spectrometry techniques such as near infrared (NIR) or mid infrared (MIR). Physiochemical techniques include fluorescence spectroscopy, nuclear magnetic resonance coupled with mass spectrometry of isotopic ratio (NMR/MSIR), ion exchange chromatography/atomic absorption spectrometry (AAS), site‐specific natural isotope fractionation by nuclear magnetic resonance (SNIF‐NMR), mid‐ and near‐infrared spectroscopy (MIRS–NIRS), Fourier transform mid‐infrared spectroscopy (FT‐MIRS), Curie point pyrolysis coupled to mass spectrometry (Cp–PyMS) and electronic NOSE coupled with mass spectrometry.
36.3 Genetic fingerprinting can provide a unique DNA profile for a given food by identifying selected genetic markers. DNA profiling requires methods such as polymerase chain reaction (PCR) to identify a given species, e.g. with fish or meat. PCR has also been used to determine the livestock origin of cheese and types of cereal. Identification of variety, breed or cultivar can be determined through the use of single nucleotide polymorphism (SNP) or PCR‐length polymorphism (PCR‐LP). Methods such as SNP and short tandem repeats (STR) can be used to verify breed and species.
36.4 PCR has been used to authenticate designated origin products such as those associated with Protected Geographic Indication (PGI) or Protected Designation of Origin (PDO). NIR has been used to determine geographic origin of fish, fish speciation, adulteration of honey with sugar and whether water has been injected into meat, and to differentiate between grape varieties, geographic origin and designation of wines. Chemical composition analysis through the use of isotope or trace element analysis identifies a ‘fingerprint’ that is specific to a given location. High‐resolution mass spectroscopy (HR‐MS) determines the isotope ratio, which can be used as a marker for the food. Comparison of isotope ratios can be undertaken using isotope ratio mass spectrometry (IRMS) or by determining the correlation of single or multiple elements in a food, sometimes called multi‐element profiling. Isotope profiles and the associated isotope mapping of supply chains has developed rapidly as a tool to verify provenance, product integrity and the authenticity of materials and products. NMR has been used to identify the country of origin or region of production of a range of products, including coffee.