Food Authenticity Assessment Research Articles

Oil Adulteration Evaluation Using High Performance Thin Layer Chromatography

Assessment of food authenticity from upstream in the supply chain is critical for the food industry. Environmental challenges and geo-political situations are causing shortages of raw materials resulting in a potential risk for food fraud. An example of this issue is the adulteration of edible oils by the addition of low-price oil, frying oil, or even non-edible grade oils mixtures threatening foods industries, consumer safety, and trust. Reliable screening tools to assess raw materials authenticity are therefore needed. Assessment of an improved alternative approach using high performance thin layer chromatography (HPTLC) is shown as a tool to evaluate edible oil authenticity and adulteration. Two methods were tested including an untargeted method based on fingerprints profiling for detection of adulteration with vegetable oil and a targeted method for mineral oil adulteration detection (e.g., paraffin wax). Statistical analysis was applied to determine acceptance criteria range to assess variability, limit of adulteration detection, and reproducibility. The robustness of the method was tested within an interlaboratory study using palm oil. Detection of adulteration with edible oils was achieved at levels from 5 to 25% while < 5% was predicted for mineral oils adulteration. Both methods showed promising results in terms of adulteration detection capability making this approach a reliable, and efficient tool to assess and monitor edible oils quality with added value in the field.

Rapid Non-Contact Detection of Chemical Warfare Agents by Laser Photoacoustic Spectroscopy.

Nerve agents have recently been used in battlefield operations, espionage wars, and terrorist attacks. These compounds, like some pesticides, cause organophosphate poisoning. The rapid, noncontact detection of a sarin simulant in the liquid phase has been demonstrated at the Diagnostics and Metrology Laboratory of the Italian National Agency for New Technologies, Energy and Sustainable Economic Development using laser photoacoustic spectroscopy, an infrared absorption technology. The first measurements, carried out with an experimental system based on a quantum cascade laser and developed for the assessment of food authenticity in the "fingerprint region", show that a detection limit of one nanolitre is within the reach of the instrument when chemometric analysis is applied.

Food Fraud Detection: The Role of Spectroscopy Coupled with Chemometrics

Food fraud is a concern for both consumers and business operators, but can simply be controlled by food industries ensuring compliance with food laws as a moral duty for authentic food quality and safety. Intentional tampering with food content at any stage of production, processing and trade, may have far reaching implication as it may constitute a risk to human, animal, plant and environmental health. Therefore, there is need for quality of a foods to be genuine and undisputed in its nature, origin, identity, and claims, and meet expected properties (i.e., authentic). Ensuring food authenticity necessitates efficient and effective tracing and tracking of food products, particularly those with low production levels visà-vis demand, coupled with high nutritional, medicinal and or economic values. Detection of food fraud remains complex when considering the complex nature of foods. Besides discussing food fraud and related terminologies, this paper focuses on the combined spectroscopy and chemometrics approach for assessment of food authenticity Understanding of the nature of fraud, gathering the appropriate datasets, establishing global partnerships (where need be), predicting vulnerability, while employing food management systems, may facilitate management and or prevention of food fraud. Viewing the complex nature of food, and then with intentional tampering with its nature, detecting fraud associated with any given food and or food product remains complex. Spectroscopy coupled with chemometrics, although sophisticated, have revealed a good fit for the job, and hand held tools such as Scio (consumer physics, which is used to scan foods in the IR range) have been made to surpass the challenge.

A Contribution to the Harmonization of Non-targeted NMR Methods for Data-Driven Food Authenticity Assessment

Spectroscopic non-targeted methods are gaining ever-growing importance in quality control and authenticity assessment of food products because of their strong potential for identification of specific features of the products by data-driven classifiers. One of the factors hampering the diffusion of spectroscopic non-targeted methods and data-driven classifiers is the lack of harmonized guidelines for their development and validation. In particular, to date, neither conditions to directly compare spectra recorded by different spectrometers nor studies demonstrating the statistical equivalence of the spectra are available. Among the spectroscopic analytical techniques suitable for the development of non-targeted methods, nuclear magnetic resonance (NMR) offers the unique opportunity to generate statistically equivalent signals. In this paper, the feasibility of NMR spectroscopy to generate statistically equivalent NMR signals from a number of different spectrometers was demonstrated for complex mixtures (aqueous extracts of wheat and flour) by organizing an inter-laboratory comparison involving 36 NMR spectrometers. Univariate statistics along with multivariate analysis were exploited to establish unbiased criteria for assessing the statistical equivalence of the NMR signals. The aspects affecting the signal equivalence were investigated, and possible solutions to reduce the extent of the human error were proposed and applied with satisfactory results. This study furnishes the scientific community with an appropriate and easy procedure to validate non-targeted NMR methods and provides error values to be used as a reference for future studies.

Mass Spectrometry-Based Untargeted Proteomics for the Assessment of Food Authenticity: The Case of Farmed Versus Wild-Type Salmon

Abstract Background: Omics technologies have been widely applied in different fields, among which, proteomics is gaining increasing interest for its application to the authenticity of food products. MS, typically coupled with LC, represents a key technique for proteomics-related studies dedicated to fish and other seafood products by using a bottom-up approach. Objective and Methods: In this paper, the optimization of an untargeted proteomics-based method using LC separation and MS detection relying on a quadrupole time-of-flight mass spectrometer is described and applied to the analysis of Canadian farmed and wild-type salmon, followed by statistical analysis based on principal component (PC) analysis. Results and Conclusions: This untargeted approach, using a data-independent acquisition MS scheme, demonstrated the ability to effectively discriminate salmon belonging to the two classes. Furthermore, selected peptides showing high loadings on PC1 could represent potential candidate peptide markers able to discriminate farmed from wild-type salmon samples in the future.

Assessing consumer attitudes and perceptions towards food authenticity

PurposeThe purpose of this paper is to identify and assess the factors that consumers evaluate significant in the assessment of food authenticity and guide them to make safe food choices.Design/methodology/approachIn this respect, a mixture model for consumer preferences, namely CUB, was employed due to the ability of discriminate features that are rated similarly allowing the detection of significant similarities and differences in consumers’ judgments. Moreover, introducing covariates in CUB models allow studying the influence that consumers’ socio-demographic characteristics have on the importance of the attributes used in the assessment of food authenticity.FindingsThe results demonstrate that organic certificate, traditional and homemade production practices, origin certificate as well as information about product’s origin country and raw materials production region are significant quality cues enable consumers to judge food authenticity. In addition, consumers further segmentation according to socio-demographic characteristics indicate that country of origin information are mainly used by middle-aged consumers, highly educated and paid, whereas production techniques and organic certification constitute the most effective indicators for judging food authenticity by older consumers.Originality/valueThe paper confirms that consumers can use extrinsic and intrinsic quality cues to judge food’s authenticity.

Mass Spectrometry-Based Untargeted Proteomics for the Assessment of Food Authenticity: The Case of Farmed Versus Wild-Type Salmon.

Background: Omics technologies have been widely applied in different fields, among which, proteomics is gaining increasing interest for its application to the authenticity of food products. MS, typically coupled with LC, represents a key technique for proteomics-related studies dedicated to fish and other seafood products by using a bottom-up approach. Objective and Methods: In this paper, the optimization of an untargeted proteomics-based method using LC separation and MS detection relying on a quadrupole time-of-flight mass spectrometer is described and applied to the analysis of Canadian farmed and wild-type salmon, followed by statistical analysis based on principal component (PC) analysis. Results and Conclusions: This untargeted approach, using a data-independent acquisition MS scheme, demonstrated the ability to effectively discriminate salmon belonging to the two classes. Furthermore, selected peptides showing high loadings on PC1 could represent potential candidate peptide markers able to discriminate farmed from wild-type salmon samples in the future.

HS-GC-IMS and chemometric data treatment for food authenticity assessment: Olive oil mapping and classification through two different devices as an example

There is a lack of official analytical methods to classify olive oil samples according to its organoleptic quality. For that, headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS) was applied and two devices with different technical configurations were compared; a commercial isothermal HS-GC-IMS with a 5 cm drift tube and a new HS-GC-IMS prototype, which works at ramped temperature and presents a 10 cm drift tube. Both devices were compared in terms of resolution, precision and classification rates (CRs) using a 30 m non-polar capillary column. Our results suggested that the resolution in the chromatographic separation was improved using the device in which a ramped temperature can be performed in a shorter analysis time and the resolution in the ion mobility separation was also better. The repeatability values (RSD) for the standards quality control were lower than 10% in both cases. Moreover, as revealed in the olive oil 2D-maps, a higher number of markers were detected by the isothermal HS-GC-IMS (91) than that for the ramped temperature device (76), probably explained by the different sensitivity of both devices. These markers were used to build chemometric models based on orthogonal partial least squares-discriminant analysis. The olive oil samples in the validation set could be classified into extra virgin, virgin and lampante, defective and non-defective, as well as edible and non-edible with CRs ranging from 83 to 100%. In order to improve the resolution, a 60 m non-polar column was used in the ramped temperature HS-GC-IMS and enabled an increase in the visualized markers to 128, but it required a longer analysis time. The repeatability values were also lower than 10% and the CRs were improved (94–100%). Finally, 21, 22 and 25 olive oil aroma compounds were identified using the isothermal (30 m column) and the ramped temperature HS-GC-IMS with 30 and 60 m columns, respectively. Although some of these markers may give clues about the olive oil category, the chemometrics processing approach offers an objective tool for a robust classification and it is easily transferable to the industry.

Novel analytical method for detection of orange juice adulteration based on ultra-fast gas chromatography

The food authenticity assessment is an increasingly important issue in food quality and safety. The application of an electronic nose based on ultra-fast gas chromatography technique enables rapid analysis of the volatile compounds from food samples. Due to the fact that this technique provides chemical profiling of natural products, it can be a powerful tool for authentication in combination with chemometrics. In this article, a methodology for classification of Not From Concentrate (NFC) juices was presented. During research samples of 100% orange juice, 100% apple juice, as well as mixtures of these juices with known percentage of base juices were tested. Classification of juice samples was carried out using unsupervised and supervised statistical methods. As chemometric methods, Hierarchical Cluster Analysis, Classification Tree, Naïve Bayes, Neural Network, and Random Forest classifiers were used. The ultra-fast GC technique coupled with supervised statistical methods allowed to distinguish juice samples containing only 1.0% of impurities. The developed methodology is a promising analytical tool to ensure the authenticity and good quality of juices.Graphical abstract

Organic food online shopping in Poland

PurposeThe purpose of this paper is to analyse selected characteristics, attitudes and opinions of organic food e-consumers (online shoppers) in Poland.Design/methodology/approachA survey was conducted among 1,000 inhabitants of Poland aged 15-65. The sample resembled the general population, regarding: age, sex, education and the size of the city of origin. In total, 63 respondents reported buying organic food online. This segment was compared with the rest of the sample with the use of two-tailed t-tests. A logistic regression model was applied to identify the determinants of organic food online shopping in Poland.FindingsIn a logistic regression model, age, income, willingness to pay (WTP) a premium price for organic food, importance attached to product appearance and to quality signs turned out to be statistically significant determinants of online shopping behaviour for organic food in Poland. Higher income, importance attached to quality signs and higher WTP increase the likelihood of being an organic e-consumer, while higher age and importance attached to product appearance decrease it.Research limitations/implicationsFirst, some determinants of organic online shopping have been identified. Second, this study has provided some frameworks to analyse organic food selection motives, barriers to the development of the market, food authenticity assessment criteria, distribution channels, and product characteristics.Practical implicationsThe findings may be useful for the industry due to the identification of the role of quality signs in online food purchases and of the importance of selected organic food consumption motives.Originality/valueTo the best of the author’s knowledge, this is the first study of organic food online shopping in Poland.

Analysis of DNA isolated from different oil sources: problems and solution

Background: One of the major aspects of traceability in food authenticity assessment is to explore practical methods to find the origin of food. Objective: The aim of the present study was to find a DNA based method for authentication and traceability of food, which are of great importance in health management. Methods: Four different DNA extraction methods were applied to obtain high pure DNA in some oil samples including olive oil, sunflower, canola and soybean oil to improve the traceability. The isolated DNA was analyzed by PCR using common primer pair, derived from the region harboring 18S rRNA/5.8S rRNA genes. Extraction methods were developed based on specific binding of DNA molecules to the silica membrane (column) or resin. Results: Our results showed that amplifiable DNA could only be extracted from olive oil in method 1, whereas the isolated DNA from other samples needed to be purified. In method 2, by pre-treating of oil with PBS and subsequent precipitation with Isopropanol, the amplification of isolated DNA was observed in sunflower, crude canola and olive oil. To remove more effectively the contaminants, method 2 was combined with chloroform and resin/Isoporopanol precipitation as method 3. Interestingly, the extracted DNA from all examined oil samples could be amplified with mentioned primers. For elimination the disadvantages of chloroform, method 4 was set up by direct usage of lysis and binding buffer. The extracted DNA from all refined oil samples could be amplified successfully. Conclusion: Based on our findings, the major problem in DNA extraction from oils is the PCR inhibitors in extracted DNA, which can be resolved by the presented methods 3 and 4.

Locally Grown, Natural Ingredients? The Isotope Ratio Can Reveal a Lot!

This communication gives an overview of selected isotope analyses applied to food authenticity assessment. Different isotope ratio detection technologies such as isotope ratio mass spectrometry (IRMS) and cavity ring down spectroscopy (CRDS) are briefly described. It will be explained how δ(18)O of water contained in fruits and vegetables can be used to assess their country of production. It will be explained why asparagus grown in Valais, in the centre of the Alps carries much less heavy water than asparagus grown closer to the sea coast. On the other hand, the use of δ(13)C can reveal whether a product is natural or adulterated. Applications including honey or sparkling wine adulteration detection will be briefly presented.

Quantitative Bioluminometric Method for DNA-Based Species/Varietal Identification in Food Authenticity Assessment

A method is reported for species quantification by exploiting single-nucleotide polymorphisms (SNPs). These single-base changes in DNA are particularly useful because they enable discrimination of closely related species and/or varieties. As a model, quantitative authentication studies were performed on coffee. These involved the determination of the percentage of Arabica and Robusta species based on a SNP in the chloroplastic trnL(UAA)-trnF(GAA) intraspacer region. Following polymerase chain reaction (PCR), the Robusta-specific and Arabica-specific fragments were subjected to 15 min extension reactions by DNA polymerase using species-specific primers carrying oligo(dA) tags. Biotin was incorporated into the extended strands. The products were captured in streptavidin-coated microtiter wells and quantified by using oligo(dT)-conjugated photoprotein aequorin. Aequorin was measured within 3 s via its characteristic flash-type bioluminescent reaction that was triggered by the addition of Ca(2+). Because of the close resemblance between the two DNA fragments, during PCR one species serves as an internal standard for the other. The percentage of the total luminescence signal obtained from a certain species was linearly related to the percent content of the sample with respect to this species. The method is accurate and reproducible. The microtiter well-based assay configuration allows high sample throughput and facilitates greatly the automation.

Food authenticity assessment: ensuring compliance with food legislation and traceability requirements

Introduction The globalisation of food markets implies that consumers come into contact with a great variety of foods, therefore European and worldwide consumers are very concerned about the origin of the food they eat. Moreover, recent food scares have added to public sensitivity regarding the origin of food and its authenticity. The objective assessment of food authenticity has thus become of paramount importance. Methods The MoniQA Network of Excellence has set up a working group on food authenticity which gathers experts from different backgrounds to address this topic, to identify any gaps and needs, and to offer legislators, control authorities and all interested parties objective, validated and harmonised means to measure food authenticity attributes. Results and conclusions In this paper, an overview of all the work done by the Food Authenticity working group during the first year of the activities of the NoE is presented. It has emerged that there are already rapid chemical and biochemical techniques that, when combined with statistical treatment of the data, have shown a degree of success. However, some basic problems remain, which need to be addressed for the successful determination of food authenticity such as sampling, method performance and uncertainty. The MoniQA Food Authenticity Working Group is working at the development of methods to authenticate foods taking into account the need of robust markers, rapid and reliable validated methods, appropriate statistical treatment of analytical data, as well as comprehensive and up-to-date databases of authenticity markers.