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- Recent Developments in the Applications of Fingerprinting Technology in the Food FieldPublication . Câmara, José S.; Medina, Sonia; Perestrelo, Rosa
- Evaluation of volatilomic fingerprint from apple fruits to ciders: a useful tool to find putative biomarkers for each apple varietyPublication . Medina, Sónia; Perestrelo, Rosa; Pereira, Regina; Câmara, José S.Aroma is a crucial criterion to assess the quality of apple fruits, juices, and ciders. The aim of this study was to explore similarities and differences in volatile profiles among apple fruits, juices, and ciders from different apple varieties (Festa, Branco, and Domingos) by headspace solid-phase microextraction gas chromatography–mass spectroscopy (HS–SPME/GC–MS). A total of 142 volatile organic compounds (VOCs) were identified, but only 9 were common in all analysed matrices and apple-tested varieties. Esters, alcohols, and aldehydes presented a higher concentration in apple fruits and juices, whereas esters, alcohols, and acids were dominant in ciders. Moreover, there were unique VOCs for each matrix and for each variety, highlighting the importance of the selection of apple varieties as an important factor to obtain good sensory and quality ciders, multiple benefits, and legal protection against the misuse of local products.
- Differential volatile organic compounds signatures of apple juices from Madeira Island according to variety and geographical originPublication . Medina, Sonia; Perestrelo, Rosa; Santos, Rui; Pereira, Regina; Câmara, José S.One of the main food authenticity issues is related to products` false labelling concerning their variety or geo graphical origin. For this reason, the aim of this study was to establish distinctive characteristics for the dis crimination of apple juices according to regional varieties (Rijo, Verde, Ribeiro and Azedo) and geographical origin (Prazeres and Santo da Serra (Madeira Island)) on the basis of their volatile pattern by headspace solid phase microextraction combined with gas chromatography mass spectrometry (HS-SPME/GC–MS) combined with chemometric tools. The results obtained revealed a perfect discrimination between the different apple varieties, with Rijo apple juices as samples with the major relative concentration of ethanol, ethyl butanoate, ethyl 2-methylbutanoate and ethyl hexanoate. Moreover, this study allowed a geographical origin-based clas sification of Azedo apple juices, highlighting ethyl acetate, 2-methyl-1-propanol, ethyl hexanoate, and toluene (described for the first time in apple juices) as discriminatory features. This study demonstrated that volatile organic compounds (VOCs) could serve as authenticity indicators to verify variety and geographical origin of apple juices, providing local producers multiple benefits and legal protection against misuse of the products.
- Food fingerprints: a valuable tool to monitor food authenticity and safetyPublication . Medina, Sonia; Pereira, Jorge A.; Silva, Pedro; Perestrelo, Rosa; Câmara, José S.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.
- Typicality assessment of onions (Allium cepa) from different geographical regions based on the volatile signature and chemometric toolsPublication . Fernandes, Sara; Góis, André; Mendes, Fátima; Perestrelo, Rosa; Medina, Sonia; Camara, José S.Onion (Allium cepa L.) is one of the main agricultural commodities produced and consumed around the world. In the present work, for the first time, the volatile signature of onions from different geographical regions of Madeira Island (Caniço, Santa Cruz, Ribeira Brava, and Porto Moniz) was tested with headspace solid-phase microextraction (HS-SPME/GC-qMS) and chemometric tools, showing that the volatile signature was affected by the geographical region of cultivation. Sulfur compounds, furanic compounds, and aldehydes are the most dominant chemical groups. Some of the identified volatile organic metabolites (VOMs) were detected only in onions cultivated in specific regions; 17 VOMs were only identified in onions cultivated at Caniço, eight in Porto Moniz, two in Santa Cruz, two in Ribeira Brava, while 12 VOMs are common to all samples from the four regions. Moreover, some VOMs belonging to sulfur compounds (dipropyl disulfide, 3-(acetylthio)-2-methylfuran), furanic compounds (dimethylmethoxyfuranone, ethyl furanone, acetyloxy-dimethylfuranone), and lactones (whiskey lactone isomer), could be applied as potential geographical markers of onions, providing a useful tool to authenticate onions by farming regions where the influence of latitude seems to be an important factor for yielding the chemical profile and may contribute to geographical protection of food and simultaneously benefiting both consumers and farmers.
- Structural/Functional Matches and Divergences of Phytoprostanes and Phytofurans with Bioactive Human OxylipinsPublication . Medina, Sonia; Gil-Izquierdo, Angel; Durand, Thierry; Ferreres, Federico; Domínguez-Perles, RaúlStructure-activity relationship (SAR) constitutes a crucial topic to discover new bioactive molecules. This approach initiates with the comparison of a target candidate with a molecule or a collection of molecules and their attributed biological functions to shed some light in the details of one or more SARs and subsequently using that information to outline valuable application of the newly identified compounds. Thus, while the empiric knowledge of medicinal chemistry is critical to these tasks, the results retrieved upon dedicated experimental demonstration retrieved resorting to modern high throughput analytical approaches and techniques allow to overwhelm the constraints adduced so far to the successful accomplishment of such tasks. Therefore, the present work reviews critically the evidences reported to date on the occurrence of phytoprostanes and phytofurans in plant foods, and the information available on their bioavailability and biological activity, shedding some light on the expectation waken up due to their structural similarities with prostanoids and isoprostanes.
- QuEChERS - Fundamentals, relevant improvements, applications and future trendsPublication . Perestrelo, Rosa; Silva, Pedro; Porto-Figueira, Priscilla; Pereira, Jorge A. M.; Silva, Catarina; Medina, Sonia; Câmara, José S.The Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) method is a simple and straightforward extraction technique involving an initial partitioning followed by an extract clean-up using dispersive solid-phase extraction (d-SPE). Originally, the QuEChERS approach was developed for recovering pesticide residues from fruits and vegetables, but rapidly gained popularity in the comprehensive isolation of analytes from different matrices. According to PubMed, since its development in 2003 up to November 2018, about 1360 papers have been published reporting QuEChERS as extraction method. Several papers have reported different improvements and modifications to the original QuEChERS protocol to ensure more efficient extractions of pH-dependent analytes and to minimize the degradation of labile analytes. This analytical approach shows several advantages over traditional extraction techniques, requiring low sample and solvent volumes, as well as less time for sample preparation. Furthermore, most of the published studies show that the QuEChERS protocol provides higher recovery rate and a better analytical performance than conventional extraction procedures. This review proposes an updated overview of the most recent developments and applications of QuEChERS beyond its original application to pesticides, mycotoxins, veterinary drugs and pharmaceuticals, forensic analysis, drugs of abuse and environmental contaminants. Their pros and cons will be discussed, considering the factors influencing the extraction efficiency. Whenever possible, the performance of the QuEChERS is compared to other extraction approaches. In addition to the evolution of this technique, changes and improvements to the original method are discussed.
- Differentiation of fresh and processed fruit juices using volatile compositionPublication . Perestrelo, Rosa; Silva, Catarina; Silva, Pedro; Medina, Sonia; Câmara, JoséIn the current study, a comprehensive approach based on headspace solid-phase microextraction (HS-SPME), combined with gas chromatography-quadrupole mass spectrometry (GC-qMS), was used to establish the volatile signature of fresh and processed fruit juices, obtained from the same batch of grapes, red fruits, orange, pear, and apple. This is a powerful tool for evaluating the impact of the production process on the volatomic pattern of fruit juice. A total of 169 volatile organic compounds (VOCs) belonging to different chemical groups were identified. Esters, carbonyl compounds, terpenoids, and alcohols are the major chemical groups in the investigated fruit juices. However, their contribution to the total volatile profile varied. Special attention should be paid to processed fruit juices to avoid the possible deleterious effects associated with the formation of furanic compounds (e.g., heat treatment), since their furanic content was significantly higher in comparison to that of fresh fruit juices. The knowledge obtained in the current study will allow for the introduction of modifications to the process involved in processing juice, which will improve the organoleptic characteristics of processed juices, contributing to a better acceptance by consumers. Furthermore, more assays should be performed to assess the effect of harvests, geography, and agronomy on the volatile profile of juices.
- Current trends and recent advances on food authenticity technologies and chemometric approachesPublication . Medina, Sonia; Perestrelo, Rosa; Silva, Pedro; Pereira, Jorge A. M.; Câmara, José S.Background: Food frauds and counterfeit products produced to obtain economic advantages have become a growing concern over the last decade. The assessment of food safety and authenticity constitute a powerful tool to mitigate this problem and protect public health. Nevertheless, the growing sophistication of fraudulent practices requires a continuous update and improvement of the analytical methodologies. Scope and approach: In this context, the advances and novel techniques and chemometric approaches reported since 2016 are discussed regarding their potential use in food authentication. This review details the main analytical techniques applied in the extraction, detection and identification of metabolites to obtain food fingerprints, emphasizing the advantages and drawbacks of each approach with practical examples. Additionally, the current legislation on food authentication has also been revised. Key findings and conclusions: GC-MS, LC- q-TOF-MS and NMR followed by PCA and PLS-DA are the most often reported analytical methodologies to discriminate between authentic and non-authentic foodstuffs using chemical fingerprints. More recently, novel and promising statistical methods with high classification power (DDSIMCA, OO-SIMCA, BPR, k-NN, among others) are being already applied. Overall, the development of nondestructive, on-siteandreal-time analyticalprocedures abletodeliverfastandunambiguous foodauthentication results will continue to be the goal driving food research.
- Current trends on microextraction by packed sorbent – fundamentals, application fields, innovative improvements and future applicationsPublication . Pereira, Jorge A. M.; Gonçalves, João; Porto-Figueira, Priscilla; Figueira, José A.; Alves, Vera; Perestrelo, Rosa; Medina, Sonia; Câmara, José S.MEPS, the acronym of microextraction by packed sorbent, is a simple, fast and user- and environmen tally-friendly miniaturization of the popular solid-phase extraction technique (SPE). In fact, it has been widely shown that MEPS can easily replace SPE for most, if not all, previous applications. It can attain this with obvious gains in sample and solvent usage, which is greatly reduced without compromising the extraction efficiency. Furthermore, MEPS can be operated with semiautomatic electronic syringes, making it very reliable and versatile, particularly to handle very low and very high sample volumes. This review will focus on the strengths and weaknesses of this technique and the different MEPS architectures commer cially available in the context of the MEPS applications reported in the last five years. Additionally, innova tive improvements will be highlighted, particularly those related with new applications and recent MEPS configurations and sorbents, such as the controlled directional flow or the innovative µSPEed variant.