NMR approach for the authentication of 10 cinnamon spice accessions analyzed via chemometric tools

Food authentication, current issues, analytical techniques, and future challenges: A comprehensive review

Food authentication and contamination are significant concerns, especially for consumers with unique nutritional, cultural, lifestyle, and religious needs. Food authenticity involves identifying food contamination for many purposes, such as adherence to religious beliefs, safeguarding health, and consuming sanitary and organic food products. This review article examines the issues related to food authentication and food fraud in recent periods. Furthermore, the development and innovations in analytical techniques employed to authenticate various food products are comprehensively focused. Food products derived from animals are susceptible to deceptive practices, which can undermine customer confidence and pose potential health hazards due to the transmission of diseases from animals to humans. Therefore, it is necessary to employ suitable and robust analytical techniques for complex and high-risk animal-derived goods, in which molecular biomarker-based (genomics, proteomics, and metabolomics) techniques are covered. Various analytical methods have been employed to ascertain the geographical provenance of food items that exhibit rapid response times, low cost, nondestructiveness, and condensability.

Application of HPLC-UV combined with chemometrics for the detection and quantification of 'true cinnamon' adulteration

Cinnamon is one of the most popular spices used in cuisines worldwide. Among its different species, Ceylon cinnamon ("true cinnamon") is the one with the most health benefits due to its high concentration in the antioxidant eugenol and the ultra-low content of the hepatotoxic compound coumarin. However, the higher price of Ceylon cinnamon makes it vulnerable to fraudulent adulteration with more economic species of cinnamon, such as Cassia and Saigon. Thus, for the detection of frauds in cinnamon samples, a HPLC-UV method was developed for the determination of 4 characteristic cinnamon compounds: eugenol, cinnamaldehyde, coumarin and cinnamic acid. The obtained data were analyzed by PLS to attain not only the authentication of cinnamon species but also the detection and quantification of partial adulterations. Several mixtures prepared in the laboratory using different cinnamon powder samples considered 'pure' Ceylon, Cassia or Saigon were tested, concluding that the proposed approach allows a clear identification of Ceylon cinnamon and a suitable quantification of the Ceylon: non-Ceylon ratio regardless of the commercial sample selected (RMSE <0.06 for both training and test sets).

Nuclear Magnetic Resonance Fingerprints and Mini DNA Markers for the Authentication of Cinnamon Species Ingredients Used in Food and Natural Health Products

Cinnamomum verum (syn C. zeylanicum) is considered 'true' cinnamon. However, it is reported that less expensive sources of cinnamon from C. cassia (syn C. aromaticum), C. loureiroi, and C. burmannii (toxic coumarin) may be used in the place of C. verum. We lack the quality assurance tools that are required to differentiate C. verum from other cinnamon species when verifying that the correct species is sourced from ingredient suppliers. The current research on cinnamon species authentication using DNA tools is limited to a few species and the use of high-quality DNA extracted from raw leaf materials. The cinnamon bark traded in the supply chain contains much less DNA and poorer-quality DNA than leaves. Our research advances DNA methods to authenticate cinnamon, as we utilized full-length chloroplast genomes via a genome skimming approach for C. burmannii and C. cassia to facilitate the design of optimal mini DNA markers. Furthermore, we developed and validated the use of NMR fingerprints for several commercial cinnamon species, including the quantification of 16 molecules. NMR fingerprints provided additional data that were useful for quality assessment in cinnamon extract powders and product consistency. Both the new mini DNA markers and NMR fingerprints were tested on commercial cinnamon products.

Selenium speciation and volatile flavor compound profiles in the edible flowers, stems, and leaves of selenium-hyperaccumulating vegetable Cardamine violifolia

Cardamine violifolia is a unique selenium (Se)-hyperaccumulating vegetable in China. The total Se content and Se speciation of three edible parts, including flowers, stems, and leaves were detected by HPLC-ICP-MS. Volatile organic compounds (VOCs) greatly impact food flavor. The VOCs of three samples were analyzed by E-nose, HS-GC-IMS, and HS-SPME-GC-MS. The results showed that the total Se content in flowers was significantly higher than that in leaves and was the lowest in stems. Organic Se accounts for more than 98% of the total Se content, primarily selenocystine, followed by methyl selenocysteine. A total of 102 VOCs were identified from C. violifolia, mainly esters, aldehydes, alcohols, and ketones. Flowers contained abundant VOCs, while stems and leaves contained fewer but similar profiles. Moreover, multivariate statistical analysis was applied to investigate the VOC variations and marker VOCs. This work can provide useful knowledge for understanding the Se characteristics and flavor of C. violifolia.

Discrimination of four Cinnamomum species by proximate, antioxidant, and chemical profiling: towards quality assessment and authenticity

Cinnamon (genus Cinnamomum) is a worldwide used spice. The highly valued, non-hepatotoxic C. verum (CV) is frequently adulterated with the cheaper hepatotoxic substitutes (C. burmannii (CB), C. cassia (CC), and C. loureiroi (CL)). Therefore, this study evaluated four major Cinnamomum species by proximate composition, antioxidant properties, and chemical analysis. The results showed that CB contained more ash and crude protein content. CC exhibited more moisture, crude fat, and nutritive value, while CV had more crude fiber and total carbohydrate content. The 80% methanol extracts of four Cinnamomum species exhibited the highest total phenolic contents (42.16 to 182.85 mg GAE/g), total flavonoid contents (0.80 to 1.07 mg QE/g), DPPH radical scavenging activities (EC50, 0.94 to 3.98 mg/mL), and ABTS radical scavenging activities (EC50, 0.09 to 0.33 mg/mL). The GC-MS based chemical profiling of CV was markedly different to those of CB, CC, and CL. Compared to the other three species, CV presented the highest eugenol content (5.77%) and the lowest coumarin content (1.90%). Principal component analysis (PCA) accounted for 94.91% of the variability, completely separating CV in quadrant I. Overall, nutritional and chemical profiles in combination with PCA could be effectively applied for monitoring Cinnamomum species, thereby ensuring food safety.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13197-023-05788-y.

Differentiating True and False Cinnamon: Exploring Multiple Approaches for Discrimination

This study presents a comprehensive literature review that investigates the distinctions between true and false cinnamon. Given the intricate compositions of essential oils (EOs), various discrimination approaches were explored to ensure quality, safety, and authenticity, thereby establishing consumer confidence. Through the utilization of physical-chemical and instrumental analyses, the purity of EOs was evaluated via qualitative and quantitative assessments, enabling the identification of constituents or compounds within the oils. Consequently, a diverse array of techniques has been documented, encompassing organoleptic, physical, chemical, and instrumental methodologies, such as spectroscopic and chromatographic methods. Electronic noses (e-noses) exhibit significant potential for identifying cinnamon adulteration, presenting a rapid, non-destructive, and cost-effective approach. Leveraging their capability to detect and analyze volatile organic compound (VOC) profiles, e-noses can contribute to ensuring authenticity and quality in the food and fragrance industries. Continued research and development efforts in this domain will assuredly augment the capacities of this promising avenue, which is the utilization of Artificial Intelligence (AI) and Machine Learning (ML) algorithms in conjunction with spectroscopic data to combat cinnamon adulteration.

Use of elemental profiles determined by energy-dispersive X-ray fluorescence and multivariate analyses to detect adulteration in Ceylon cinnamon

The price of Cinnamomum verum (Ceylon cinnamon) is around twice as high as that of the other cinnamon varieties commonly grouped under the name cassia cinnamon, making the former spice an attractive target for fraudsters. This work demonstrates that elemental profiles obtained by energy-dispersive X-ray fluorescence in combination with multivariate analyses can be used as a screening method to detect Ceylon cinnamon adulteration. Thirty-six elements were analysed in 52 commercially available cinnamon samples, 29 Ceylon, 8 cassia, and 15 for which no indication about variety was provided. Fifty-eight percent of the samples were either adulterated or did not meet international quality criteria. Four of the ground cinnamon samples labelled as Ceylon cinnamon were found to be pure cassia or a mixture with a high cassia content, and 26 samples were suspected of other types of adulteration including replacement of bark with other parts of the cinnamon tree. Headspace gas chromatography-mass spectrometry and ash determination by thermogravimetric analysis confirmed the conclusions reached by elemental analysis. Only one sample labelled as Ceylon cinnamon and that according to its volatile composition was cassia cinnamon was not flagged as suspicious by elemental analysis.

Untargeted 1H NMR-based metabolomics and multi-technique data fusion: A promising combined approach for geographical and processing authentication of thyme by multivariate statistical analysis

Thyme is a culinary herb highly susceptible to increasing mislabeling occurring in the spice industry. In this study, proton nuclear magnetic resonance spectroscopy (¹H NMR) combined with multivariate statistics was successfully applied with two authenticity purposes: (1) tracing thyme metabolic differences among three relevant geographical regions (Morocco, Spain, and Poland), and (2) assessing the influence of sterilization processing on the metabolic fingerprint. Multivariate data analysis provided six and seven key geographical and processing markers, respectively, including thymol, organic acids, chlorogenic acid, and some carbohydrates (e.g., sucrose). Additionally, for the first time, a mid-level data fusion approach was tested for thyme authenticity combining three complementary and synergic analytical platforms: gas and liquid chromatography coupled with high-resolution mass spectrometry, and ¹H NMR spectroscopy, providing a comprehensive metabolomics insight into the origin and processing effects on thyme fingerprinting, and opening the path to new metabolomics approaches for quality control in the spice industry.

Rapid and non-destructive cinnamon authentication by NIR-hyperspectral imaging and classification chemometrics tools

Cinnamon is a valuable aromatic spice widely used in pharmaceutical and food industry. Commonly, two-cinnamon species are available in the market, Cinnamomum verum (true cinnamon), cropped only in Sri Lanka, and Cinnamomum cassia (false cinnamon), cropped in different geographical origins. Thus, this work aimed to develop classification models based on NIR-hyperspectral imaging (NIR-HSI) coupled to chemometrics to classify C. verum and C. cassia sticks. First, principal component analysis (PCA) was applied to explore hyperspectral images. Scores surface displayed the high similarity between species supported by comparable macronutrient concentration. PC3 allowed better class differentiation compared to PC1 and PC2, with loadings exhibiting peaks related to phenolics/aromatics compounds, such as coumarin (C. cassia) or catechin (C. verum). Partial least square discriminant analysis (PLS-DA) and Support vector machine (SVM) reached similar performance to classify samples according to origin, with error = 3.3 % and accuracy = 96.7 %. A permutation test with p < 0.05 validated PLS-DA predictions have real spectral data dependency, and they are not result of chance. Pixel-wise (approach A) and sample-wise (approach B, C and D) classification maps reached a correct classification rate (CCR) of 98.3 % for C. verum and 100 % for C. cassia. NIR-HSI supported by classification chemometrics tools can be used as reliable analytical method for cinnamon authentication.

Simultaneous quantification of microplastic particles by non-deuterated (NoD) 1H-qNMR from samples comprising different polymer types

Facing microplastic contamination and thereby its impacts on the environment and health will probably be one of the most concerning challenges in our immediate future. Yet, data on these emerging pollutants are still scarce in many aspects leading to the ongoing development and expansion of analytical procedures and approaches. In recent years, despite being used formerly only for qualitative aspects, nuclear magnetic resonance spectroscopy (NMR) was introduced for the quantification of microplastic particles. By the combination of linear regression procedures, internal standards and the integration of proton NMR, the so-called qNMR method allows mass-based quantification of microplastics in a limited amount of time and independent of particle size. Based on this approach, further optimization through the simultaneous dissolution and quantification of multiple polymers is investigated. Individual requirements, known issues and considerations will be demonstrated along with additional possibilities for five polymers: polystyrene (PS), butadiene rubber (BR), polyvinylchloride (PVC), polyethylene terephthalate (PET) and polyamide (PA). The applicability of homopolymer-based calibrations is demonstrated for both the quantification of multiple homopolymers dissolved in a shared solvent system and the quantification of copolymers; for example, a styrene-butadiene copolymer (SBR). Linearities and limits of detection and quantification as well as precision and accuracy comparable to those of solely measured microplastic particles are achieved. The improvement significantly reduces the preparation and measurement time in combination with lowered costs. In addition, enhanced reliability was achieved by implementing hexamethyldisiloxane (HMDSO) as an internal standard in NoD measurements, replacing dichloromethane (DCM).

Integrated comparative metabolite profiling via NMR and GC-MS analyses for tongkat ali (Eurycoma longifolia) fingerprinting and quality control analysis

Tongkat ali commonly known as Malaysian Ginseng (Eurycoma longifolia) is a herbal root worldwide available in nutraceuticals, either as a crude powder or capsules blended with other herbal products. Herein, a multiplexed metabolomics approach based on nuclear magnetic resonance (NMR) and solid-phase microextraction combined with gas chromatography-mass spectrometry (SPME-GC-MS) was applied for authentic tongkat ali extract vs some commercial products quality control analysis. NMR metabolite fingerprinting identified 15 major metabolites mostly ascribed to sugars, organic and fatty acids in addition to quassinoids and cinnamates. Following that, multivariate analysis as the non-supervised principal component analysis (PCA) and supervised orthogonal partial least squares-discriminant analysis (OPLS-DA) were applied revealing that differences were related to fatty acids and 13,21-dihydroeurycomanone being more enriched in authentic root. SPME-GC-MS aroma profiling led to the identification of 59 volatiles belonging mainly to alcohols, aldehydes/furans and sesquiterpene hydrocarbons. Results revealed that aroma of commercial products showed relatively different profiles being rich in vanillin, maltol, and methyl octanoate. Whereas E-cinnamaldehyde, endo-borneol, terpinen-4-ol, and benzaldehyde were more associated to the authentic product. The present study shed the light for the potential of metabolomics in authentication and standardization of tongkat ali and identification of its true flavor composition.

Future perspectives on aptamer for application in food authentication

Food fraudulence and food contamination are major concerns, particularly among consumers with specific dietary, cultural, lifestyle, and religious requirements. Current food authentication methods have several drawbacks and limitations, necessitating the development of a simpler, more sensitive, and rapid detection approach for food screening analysis, such as an aptamer-based biosensor system. Although the use of aptamer is growing in various fields, aptamer applications for food authentication are still lacking. In this review, we discuss the limitations of existing food authentication technologies and describe the applications of aptamer in food analyses. We also project several potential targets or marker molecules to be targeted in the SELEX process. Finally, this review highlights the drawbacks of current aptamer technologies and outlines the potential route of aptamer selection and applications for successful food authentication. This review provides an overview of the use of aptamer in food research and its potential application as a molecular reporter for rapid detection in food authentication process. Developing databases to store all biochemical profiles of food and applying machine learning algorithms against the biochemical profiles are urged to accelerate the identification of more reliable biomarker molecules as aptamer targets for food authentication.

Comparative Metabolite Profiling and Fingerprinting of Medicinal Cinnamon Bark and Its Commercial Preparations via a Multiplex Approach of GC–MS, UV, and NMR Techniques

Various species of cinnamon (Cinnamomum sp.) are consumed as traditional medicine and popular spice worldwide. The current research aimed to provide the first comparative metabolomics study in nine cinnamon drugs and their different commercial preparations based on three analytical platforms, i.e., solid-phase microextraction coupled to gas chromatography–mass spectrometry method (SPME/GC–MS), nuclear magnetic resonance (NMR), and ultraviolet-visible spectrophotometry (UV/Vis) targeting its metabolome. SPME/GC–MS of cinnamon aroma compounds showed a total of 126 peaks, where (E)-cinnamaldehyde was the major volatile detected at 4.2–60.9% and 6.3–64.5% in authenticated and commercial preparations, respectively. Asides, modeling of the GC/MS dataset could relate the commercial products CP-1 and CP-3 to C. cassia attributed to their higher coumarin and low (E)-cinnamaldehyde content. In contrast, NMR fingerprinting identified (E)-methoxy cinnamaldehyde and coumarin as alternative markers for C. verum and C. iners, respectively. Additionally, quantitative NMR (qNMR) standardized cinnamon extracts based on major metabolites. UV/Vis showed to be of low discrimination power, but its orthogonal projections to latent structures discriminant analysis (OPLS-DA) S-plot showed that C. iners was more abundant in cinnamic acid compared to other samples. Results of this study provide potential insights into cinnamon drugs QC analysis and identify alternative markers for their discrimination.

NMR-Driven Identification of Cinnamon Bud and Bark Components With Anti-Aβ Activity

The anti-Alzheimer disease (AD) activity reported for an aqueous cinnamon bark extract prompted us to investigate and compare the anti-amyloidogenic properties of cinnamon extracts obtained from both bark and bud, the latter being a very little explored matrix. We prepared the extracts with different procedures (alcoholic, hydroalcoholic, or aqueous extractions). An efficient protocol for the rapid analysis of NMR spectra of cinnamon bud and bark extracts was set up, enabling the automatic identification and quantification of metabolites. Moreover, we exploited preparative reverse-phase (RP) chromatography to prepare fractions enriched in polyphenols, further characterized by UPLC-HR-MS. Then, we combined NMR-based molecular recognition studies, atomic force microscopy, and in vitro biochemical and cellular assays to investigate the anti-amyloidogenic activity of our extracts. Both bud and bark extracts showed a potent anti-amyloidogenic activity. Flavanols, particularly procyanidins, and cinnamaldehydes, are the chemical components of cinnamon hindering Aβ peptide on-pathway aggregation and toxicity in a human neuroblastoma SH-SY5Y cell line. Together with the previously reported ability to hinder tau aggregation and filament formation, these data indicate cinnamon polyphenols as natural products possessing multitarget anti-AD activity. Since cinnamon is a spice increasingly present in the human diet, our results support its use to prepare nutraceuticals useful in preventing AD through an active contrast to the biochemical processes that underlie the onset of this disease. Moreover, the structures of cinnamon components responsible for cinnamon anti-AD activities represent molecular templates for designing and synthesizing new anti-amyloidogenic drugs.

Comparative Metabolite Fingerprinting of Four Different Cinnamon Species Analyzed via UPLC-MS and GC-MS and Chemometric Tools

The present study aimed to assess metabolites heterogeneity among four major Cinnamomum species, including true cinnamon (Cinnamomum verum) and less explored species (C. cassia, C. iners, and C. tamala). UPLC-MS led to the annotation of 74 secondary metabolites belonging to different classes, including phenolic acids, tannins, flavonoids, and lignans. A new proanthocyanidin was identified for the first time in C. tamala, along with several glycosylated flavonoid and dicarboxylic fatty acids reported for the first time in cinnamon. Multivariate data analyses revealed, for cinnamates, an abundance in C. verum versus procyandins, dihydro-coumaroylglycosides, and coumarin in C. cassia. A total of 51 primary metabolites were detected using GC-MS analysis encompassing different classes, viz. sugars, fatty acids, and sugar alcohols, with true cinnamon from Malaysia suggested as a good sugar source for diabetic patients. Glycerol in C. tamala, erythritol in C. iners, and glucose and fructose in C. verum from Malaysia were major metabolites contributing to the discrimination among species.

NMR Metabolome-Based Classification of Cymbopogon Species: a Prospect for Phyto-equivalency of its Different Accessions Using Chemometric Tools

Cymbopogon species are widely distributed worldwide and known for their high essential oil content with potential commercial and medicinal benefits justifying for their inclusion in food and cosmetics. Most species received scant characterization regarding their full complement of bioactive constituents necessary to explain their medicinal activities. In this study, the metabolite profiles of 5 Cymbopogon species, C. citratus, C. flexuosus, C. procerus, C. martini, and C. nardus, were characterized via NMR-based metabolomics. The results of 13 shoot accessions revealed the identification and quantification of 23 primary and secondary metabolites belonging to various compound classes. Multivariate analyses were used for species classification, though found not successful in discrimination based on geographical origin. Nevertheless, C. citratus was found particularly enriched in neral, geranial, (E)-aconitic acid, isoorientin, and caffeic acid as the major characterizing metabolites compared to other species, while an unknown apigenin derivative appeared to discriminate C. martini. The high essential oil and phenolic content in C. citratus emphasizes its strong antioxidant activity, whereas (E)-aconitic acid accounts for its traditional use as insecticide. This study affords the first insight into metabolite compositional differences among Cymbopogon species. Moreover, antimicrobial, insecticidal, antidiabetic, and antioxidant compounds were identified that can be utilized as biomarkers for species authentication.

Metabolite Fingerprinting Based on 1H-NMR Spectroscopy and Liquid Chromatography for the Authentication of Herbal Products

Herbal medicines (HMs) are regarded as one of the traditional medicines in health care to prevent and treat some diseases. Some herbal components such as turmeric and ginger are used as HMs, therefore the identification and confirmation of herbal use are very necessary. In addition, the adulteration practice, mainly motivated to gain economical profits, may occur by substituting the high price of HMs with lower-priced ones or by addition of certain chemical constituents known as Bahan Kimia Obat (chemical drug ingredients) in Indonesia. Some analytical methods based on spectroscopic and chromatographic methods are developed for the authenticity and confirmation of the HMs used. Some approaches are explored during HMs authentication including single-component analysis, fingerprinting profiles, and metabolomics studies. The absence of reference standards for certain chemical markers has led to exploring the fingerprinting approach as a tool for the authentication of HMs. During fingerprinting-based spectroscopic and chromatographic methods, the data obtained were big, therefore the use of chemometrics is a must. This review highlights the application of fingerprinting profiles using variables of spectral and chromatogram data for authentication in HMs. Indeed, some chemometrics techniques, mainly pattern recognition either unsupervised or supervised, were applied for this purpose.

Application of spectroscopic techniques and chemometric methods to differentiate between true cinnamon and false cinnamon

The objective of this study was to identify useful chemical markers for the differentiation of true and false cinnamon; to develop a fast and efficient method of differentiation using MIR associated with chemometric methods. A total of 129 cinnamon samples from 3 countries (Brazil, Sri Lanka, and Paraguay) were purchased, being differentiated by visual analysis. The bioactive compounds, antioxidant activity, HPLC, and MIR analysis were performed. The data obtained were submitted to PCA and PLS-DA. The results showed that the samples of true cinnamon have a higher concentration of eugenol, cinnamaldehyde, and antioxidant capacity, as well as a lower coumarin content. The PCA showed the separation of two groups of cinnamon samples. PLS-DA was effective in differentiating the studied samples with an accuracy of 94.44% and 100% for the composition and MIR analysis, respectively. The MIR proved to be an alternative for the rapid differentiation of true and false cinnamon.

Agricultural Potentials of Molecular Spectroscopy and Advances for Food Authentication: An Overview

Meat, fish, coffee, tea, mushroom, and spices are foods that have been acknowledged for their nutritional benefits but are also reportedly targets of fraud and tampering due to their economic value. Conventional methods often take precedence for monitoring these foods, but rapid advanced instruments employing molecular spectroscopic techniques are gradually claiming dominance due to their numerous advantages such as low cost, little to no sample preparation, and, above all, their ability to fingerprint and detect a deviation from quality. This review aims to provide a detailed overview of common molecular spectroscopic techniques and their use for agricultural and food quality management. Using multiple databases including ScienceDirect, Scopus, Web of Science, and Google Scholar, 171 research publications including research articles, review papers, and book chapters were thoroughly reviewed and discussed to highlight new trends, accomplishments, challenges, and benefits of using molecular spectroscopic methods for studying food matrices. It was observed that Near infrared spectroscopy (NIRS), Infrared spectroscopy (IR), Hyperspectral imaging (his), and Nuclear magnetic resonance spectroscopy (NMR) stand out in particular for the identification of geographical origin, compositional analysis, authentication, and the detection of adulteration of meat, fish, coffee, tea, mushroom, and spices; however, the potential of UV/Vis, 1H-NMR, and Raman spectroscopy (RS) for similar purposes is not negligible. The methods rely heavily on preprocessing and chemometric methods, but their reliance on conventional reference data which can sometimes be unreliable, for quantitative analysis, is perhaps one of their dominant challenges. Nonetheless, the emergence of handheld versions of these techniques is an area that is continuously being explored for digitalized remote analysis.

Chemometric-Guided Approaches for Profiling and Authenticating Botanical Materials

Botanical supplements with broad traditional and medicinal uses represent an area of growing importance for American health management; 25% of U.S. adults use dietary supplements daily and collectively spent over $9. 5 billion in 2019 in herbal and botanical supplements alone. To understand how natural products benefit human health and determine potential safety concerns, careful in vitro, in vivo, and clinical studies are required. However, botanicals are innately complex systems, with complicated compositions that defy many standard analytical approaches and fluctuate based upon a plethora of factors, including genetics, growth conditions, and harvesting/processing procedures. Robust studies rely upon accurate identification of the plant material, and botanicals' increasing economic and health importance demand reproducible sourcing, as well as assessment of contamination or adulteration. These quality control needs for botanical products remain a significant problem plaguing researchers in academia as well as the supplement industry, thus posing a risk to consumers and possibly rendering clinical data irreproducible and/or irrelevant. Chemometric approaches that analyze the small molecule composition of materials provide a reliable and high-throughput avenue for botanical authentication. This review emphasizes the need for consistent material and provides insight into the roles of various modern chemometric analyses in evaluating and authenticating botanicals, focusing on advanced methodologies, including targeted and untargeted metabolite analysis, as well as the role of multivariate statistical modeling and machine learning in phytochemical characterization. Furthermore, we will discuss how chemometric approaches can be integrated with orthogonal techniques to provide a more robust approach to authentication, and provide directions for future research.

Discrimination of Four Cinnamomum Species with Physico-Functional Properties and Chemometric Techniques: Application of PCA and MDA Models

Discrimination of highly valued and non-hepatotoxic Cinnamomum species (C. verum) from hepatotoxic (C. burmannii, C. loureiroi, and C. cassia) is essential for preventing food adulteration and safety problems. In this study, we developed a new method for the discrimination of four Cinnamomum species using physico-functional properties and chemometric techniques. The data were analyzed through principal component analysis (PCA) and multiclass discriminant analysis (MDA). The results showed that the cumulative variability of the first three principal components was 81.70%. The PCA score plot indicated a clear separation of the different Cinnamomum species. The training set was used to build the discriminant MDA model. The testing set was verified by this model. The prediction rate of 100% proved that the model was valid and reliable. Therefore, physico-functional properties coupled with chemometric techniques constitute a practical approach for discrimination of Cinnamomum species to prevent food fraud.

Spices and Seasoning Mixes in European Union-Innovations and Ensuring Safety

Spices are an important group of food products of great importance in nutrition and food technology. They are mainly used to shape the sensory properties of food in gastronomy, in home cooking, and in industry. Ensuring quality and safety is one of the basic tasks of spice producers. The aim of this review is to present the threats to the consumer related to the presence of spices and seasoning mixes in the diet. Therefore, special attention was paid to such risks as excess sodium chloride (and sodium) in spice mixtures, the use of additives influencing the sensory experience, and irregularities in the labeling of spices and seasoning mixes for the presence of additives and allergens. The threats regarding microbiological safety and the presence of heavy metals, pesticides, plant protection products, as well as synthetic fertilizers and undeclared additives are also presented and the issue of adulteration and lack of authenticity of spices and spice mixtures is discussed. Using data from IJHARS planned inspections and notifications registered in the EU Rapid Alert System for Food and Feed (RASFF) for 2015-2019, as well as the results of own research, an analysis of the risks caused by herbs and spices was carried out. Strategic activities of companies producing spices focus, among others, on improving production and expanding the commercial offer with new, attractive products. The article reviews product and process innovations in spice mixes and the methods of ensuring safety in this group of food products.

Metabolomic Profiles of Essential Oils from Selected Rosa Varieties and Their Antimicrobial Activities

This study aimed to analyze the essential oils of the aerial parts (A) and flowers (F) of Rosa banksiae var. banksiae Ait. (RBW), Rosa polyantha Thunb. "orange fairy" (RPO) and Rosa polyantha Thunb. "white fairy" (RPW), family Rosaceae, and perform multivariate data analyses and antimicrobial activity evaluations. The essential oil analyses were performed by GC/FID and GC/MS. Principal component analysis (PCA), hierarchical cluster analysis (HCA), and clustered heat map were used for the multivariate analyses. The antimicrobial activity was evaluated by the well-diffusion method against four bacteria and four fungi. Two hundred fifty-three compounds were identified from the six oil samples. The major components in RBW-A, RPO-A, and RPW-A were n-undecane (14.40, 19.36, and 9.21%) n-dodecane (14.54, 22.13, and 8.39%), and yomogi alcohol (8.41, 10.53, and 6.28%), respectively, whereas RBW-F, RPO-F and RPW-F contained n-heptadecane (16.70%), n-undecane (7.98%), and β-phellandrene (22.78%), respectively. The tested essential oils showed moderate antifungal activity against Aspergillus fumigatus compared to amphotericin B. PCA and HCA revealed five main clusters. The six samples carried close chemical profiles and can be regarded as fruitful sources of safe antifungal agents.

Comparison of various commercially available cinnamon barks using NMR metabolomics and the quantification of coumarin by quantitative NMR methods

Cinnamon bark is an important spice worldwide. In this study, the chemical diversity of various commercially available cinnamon barks that differed in their production areas and utility applications (culinary spice or medicines) were investigated by the use of ¹H NMR metabolomics. Our results indicated that principle component analysis (PCA) and hierarchical cluster analysis (HCA) of the ¹H NMR spectra of the cinnamon bark methanolic extracts including the deduction of their species by nucleotide sequence analysis enabled differentiation of the cinnamon barks according to their species, production areas and utility applications. The constituents of Vietnam cinnamon were found to differ significantly from the other samples investigated based on PCA score plots and HCA constellation dendrograms. Coumarin was found to be a key compound for the discrimination of Vietnamese cinnamon by multivariate analysis of the ¹H NMR spectral data and direct comparison of the ¹H NMR spectra. In addition, coumarin was quantified using quantitative NMR methods. As a result, coumarin was contained in Vietnamese cinnamon at a higher level compared to other cinnamons. This study indicated that ¹H NMR metabolomics could deduce spices, utility, and producing area of commercially available cinnamon barks. Furthermore, combining quantitative ¹H NMR methods with ¹H NMR metabolomics enable quantification of coumarin in cinnamon bark on a single measurement.

Applicability of high-resolution NMR in combination with chemometrics for the compositional analysis and quality control of spices and plant-derived condiments

Over the last years, the consumption of spices and plant-derived condiments has increased considerably, owing to new culinary trends. Unfortunately, the current marketing channels make them highly vulnerable to adulteration and food fraud. High-resolution nuclear magnetic resonance (NMR) is a powerful tool for the compositional study of spices and plant-derived condiments. It allows the chemical characterization of a wide range of polar and non-polar metabolites, and provides unique structural information not available by other techniques. The chemometric-based analysis of NMR 'fingerprints' has been used to discriminate samples according to species and geographical origin and to detect adulterations, among other applications. The comprehensive identification and quantification of marker compounds can be achieved even in complex mixtures, demonstrating a great potential for high-throughtput quality control applications. © 2020 Society of Chemical Industry.

Nuclear Magnetic Resonance Metabolomics Approach for the Analysis of Major Legume Sprouts Coupled to Chemometrics

Legume sprouts are a fresh nutritive source of phytochemicals of increasing attention worldwide owing to their many health benefits. Nuclear magnetic resonance (NMR) was utilized for the metabolite fingerprinting of 4 major legume sprouts, belonging to family Fabaceae, to be exploited for quality control purposes. Thirty-two metabolites were identified belonging to different classes, i.e., fatty acids, sugars, amino acids, nucleobases, organic acids, sterols, alkaloids, and isoflavonoids. Quantitative NMR was employed for assessing the major identified metabolite levels and multivariate data analysis was utilized to assess metabolome heterogeneity among sprout samples. Isoflavones were detected exclusively in Cicer sprouts, whereas Trigonella was characterized by 4-hydroxyisoleucine. Vicia sprouts were distinguished from other legume sprouts by the presence of L-Dopa versus acetate abundance in Lens. A common alkaloid in all sprouts was trigonelline, detected at 8–25 µg/mg, suggesting its potential role in legume seeds’ germination. Trigonelline was found at highest levels in Trigonella sprouts. The aromatic NMR region data (δ 11.0–5.0 ppm) provided a better classification power than the full range (δ 11.0–0.0 ppm) as sprout variations mostly originated from secondary metabolites, which can serve as chemotaxonomic markers.

The Application of NMR Spectroscopy and Chemometrics in Authentication of Spices

Spices and herbs are among the most commonly adulterated food types. This is because spices are widely used to process food. Spices not only enhance the flavor and taste of food, but they are also sources of numerous bioactive compounds that are significantly beneficial for health. The healing effects of spices are connected with their antimicrobial, anti-inflammatory and carminative properties. However, regular consumption of adulterated spices may cause fatal damage to our system because adulterants in most cases are unhealthy. For that reason, the appropriate analytical methods are necessary for quality assurance and to ensure the authenticity of spices. Spectroscopic methods are gaining interest as they are fast, require little or no sample preparation, and provide rich structural information. This review provides an overview of the application of NMR spectroscopy combined with chemometric analysis to determine the quality and adulteration of spices.

Sensory Metabolite Profiling in a Date Pit Based Coffee Substitute and in Response to Roasting as Analyzed via Mass Spectrometry Based Metabolomics

Interest in developing coffee substitutes is on the rise, to minimizing its health side effects. In the Middle East, date palm (Phoenix dactylifera L.) pits are often used as a coffee substitute post roasting. In this study, commercially-roasted date pit products, along with unroasted and home-prepared roasted date pits, were subjected to analyses for their metabolite composition, and neuropharmacological evaluation in mice. Headspace SPME-GCMS and GCMS post silylation were employed for characterizing its volatile and non-volatile metabolite profile. For comparison to roasted coffee, coffee product was also included. There is evidence that some commercial date pit products appear to contain undeclared additives. SPME headspace analysis revealed the abundance of furans, pyrans, terpenoids and sulfur compounds in roasted date pits, whereas pyrroles and caffeine were absent. GCMS-post silylation employed for primary metabolite profiling revealed fatty acids’ enrichment in roasted pits versus sugars’ abundance in coffee. Biological investigations affirmed that date pit showed safer margin than coffee from its LD₅₀, albeit it exhibits no CNS stimulant properties. This study provides the first insight into the roasting impact on the date pit through its metabolome and its neuropharmacological aspects to rationalize its use as a coffee substitute.

Nuclear Magnetic Resonance (NMR) Spectroscopy in Food Science: A Comprehensive Review

Nuclear magnetic resonance (NMR) spectroscopy is a robust method, which can rapidly analyze mixtures at the molecular level without requiring separation and/or purification steps, making it ideal for applications in food science. Despite its increasing popularity among food scientists, NMR is still an underutilized methodology in this area, mainly due to its high cost, relatively low sensitivity, and the lack of NMR expertise by many food scientists. The aim of this review is to help bridge the knowledge gap that may exist when attempting to apply NMR methodologies to the field of food science. We begin by covering the basic principles required to apply NMR to the study of foods and nutrients. A description of the discipline of chemometrics is provided, as the combination of NMR with multivariate statistical analysis is a powerful approach for addressing modern challenges in food science. Furthermore, a comprehensive overview of recent and key applications in the areas of compositional analysis, food authentication, quality control, and human nutrition is provided. In addition to standard NMR techniques, more sophisticated NMR applications are also presented, although limitations, gaps, and potentials are discussed. We hope this review will help scientists gain some of the knowledge required to apply the powerful methodology of NMR to the rich and diverse field of food science.

Food fingerprints - A valuable tool to monitor food authenticity and safety

In recent years, food frauds and adulterations have increased significantly. This practice is motivated by fast economical gains and has an enormous impact on public health, representing an important issue in food science. In this context, this review has been designed to be a useful guide of potential biomarkers of food authenticity and safety. In terms of food authenticity, we focused our attention on biomarkers reported to specify different botanical or geographical origins, genetic diversity or production systems, while at the food safety level, molecular evidences of food adulteration or spoilage will be highlighted. This report is the first to combine results from recent studies in a format that allows a ready overview of metabolites (<1200 Da) and potentially molecular routes to monitor food authentication and safety. This review has therefore the potential to unveil important aspects in food adulteration and safety, contributing to improve the current regulatory frameworks.