Loading...
5 results
Search Results
Now showing 1 - 5 of 5
- 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.
- 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.
- Untargeted fingerprinting of cider volatiles from different geographical regions by HS-SPME/GC-MSPublication . Perestrelo, Rosa; Silva, Catarina L.; Silva, Pedro; Medina, Sonia; Pereira, Regina; Câmara, José S.The volatomic fingerprint of ciders produced in different geographical regions from Madeira Island was estab lished using headspace solid phase microextraction combined with gas chromatography mass spectrometry (HS SPME/GC–MS) in order to explore the effects of geographical region on the volatile pattern ciders in addition to identify potential molecular geographic markers. A total of 107 volatile organic compounds (VOCs) belonging to different chemical families were identified from which 50 VOCs are common to all ciders analysed. Significant differences in the relative content of VOCs from ciders of different geographical regions were observed. The potential of the identified VOCs for ciders discrimination according to region was assessed through chemometric tools, such as principal components analysis (PCA) and partial least squares-discriminant analysis (PLS-DA). The PCA showed significant differences among ciders from different island geographical regions. Fifteen VOCs re sponsible for ciders discrimination were identified by PLS-DA. Fifteen VOCs, namely five terpenoids, four al cohols, three acids and three esters, present variable importance in projection (VIP) values higher than one. Our findings provide relevant information related to volatile signature of ciders produced in Madeira Island, which may be a useful tool to cider-making process contributing to improve the quality of the final product. In addition, the geographical discrimination recognizes the unique and distinctive characteristics that will allow in the future to protect the quality and typicity of products originating in certain geographical regions.