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- Establishment of authenticity and typicality of sugarcane honey based on volatile profile and multivariate analysisPublication . Silva, Pedro; Freitas, Jorge; Silva, Catarina L.; Perestrelo, Rosa; Nunes, Fernando M.; Câmara, José S.Sugarcane honey (SCH) is a black syrup produced in Madeira Island widely known for their excellent quality being used in traditional pastry and confectionery. However, its notoriety has been affected by circumstances in which some producers do not guaranty the product quality. The purpose of this study was to establish, for the first time, the volatomic profile of SCH produced by certified and non-certified producers in order to define their authenticity and typicality as useful platform to ensure SCH safety, protect consumer interests and fight the continuous problems of food fraud and adulteration. Solid-phase microextraction in headspace mode (HS-SPME) combined with gas chromatography-mass spectrometry (GC-MS) was applied as high throughput approach for extraction, separation and identification of SCH volatile compounds. The extraction technique was optimized for nature of stationary phase, extraction temperature, extraction time, and validated according with IUPAC and AOAC guidelines. Different volatomic fingerprints for SCH from certified and non-certified producers were recognized, being identified up to 87 volatile organic compounds (VOCs) belonging to distinct chemical classes, mainly aldehydes, alcohols, ketones and furans. One-way ANOVA analysis showed the existence of 18 VOCs with statistically significant differences between volatile profiles from certified and non-certified producers. Principal component analysis (PCA) and linear discriminant analysis (LDA) differentiate and discriminate the samples from both type of producers. According to the obtained results, the followed strategy revealed an effective way to establish the authenticity and typicality of SCH, providing useful information to producers that might therefore be used to improve the SCH quality and a powerful platform to promote a European certification application.
- A fast and environment-friendly MEPS PEP /UHPLC-PDA methodology to assess 3-hydroxy-4,5-dimethyl-2(5H)-furanone in fortified winesPublication . Freitas, Jorge; Perestrelo, Rosa; Cassaca, Rubina; Castillo, Mariangie; Santos, Mariana; Pereira, Jorge; Câmara, José S.Sotolon is widely associated with the quality of fortified aged wines, and has also been linked to premature oxidative aging (premox). Here we developed a single, fast and environmental-friendly microextraction by packed sorbent ultra-high pressure liquid chromatography analysis (MEPS/UHPLC-PDA) for sotolon quantification in different wines. The best extraction conditions (loading three times 250μL samples through the MEPSPEP sorbent and elution with 100μL of 50% MeOH) were combined with a fast UHPLC separation (5min separation using acidified 10% MeOH isocratic flow in a CORTECS C18 column) to allow unparalleled minimum sample and solvents volumes usage. The validated methodology showed good linearity (r(2)>0.993) and precision (<5.6%); high recovery (>81%) and detection limits (0.45-2.51μg/L) far below sotolon odor threshold for any type of wine. The methodology was successfully applied to selected white table and Madeira wines, encompassing therefore a wide range of alcohol and sugar contents. Furthermore, as far we may know, this is the first time a single methodology can be used to assess both wine aging or premox according to the type of wine.
- Emerging contaminants in seafront zones. Environmental impact and analytical approachesPublication . Câmara, José S.; Montesdeoca-Esponda, Sarah; Freitas, Jorge; Guedes-Alonso, Rayco; Sosa-Ferrera, Zoraida; Perestrelo, RosaSome chemical substances have the potential to enter the coastal and marine environment and cause adverse effects on ecosystems, biodiversity and human health. For a large majority of them, their fate and effects are poorly understood as well as their use still unregulated. Finding effective and sustainable strategies for the identification of these emerging and/or anthropogenic contaminants that might cause polluting effects in marine environments to mitigate their adverse effects, is of utmost importance and a great challenge for managers, regulators and researchers. In this review we will evaluate the impact of emerging contaminants (ECs) on marine coastal zones namely in their ecosystems and biodiversity, highlighting the potential risks of organic pollutants, pharmaceuticals and personal care products. Emerging microextraction techniques and high-resolution analytical platforms used in isolation, identification and quantification of ECs will be also reviewed.
- Improved approach based on MALDI-TOF MS for establishment of the fish mucus protein pattern for geographic discrimination of Sparus aurataPublication . Freitas, Jorge; Silva, Pedro; Perestrelo, Rosa; Vaz-Pires, Paulo; Câmara, José S.Food fraud is still a recurrent practice throughout food supply chains. In the case of seafood, misidentification of species and products repackaging constitute the most common frauds. Therefore, the development of appropriate analytical approaches to be used against food fraud is necessary. The present study goal is to explore for the first time, the possibility to differentiate between Sparus aurata from two different mariculture farms located in Madeira Island (Caniçal and Ribeira Brava), using the mass fingerprint of fish mucus obtained from MALDI-TOF MS and analyzed using Mass-UP software for multivariate statistical analysis and biomarker identification. It was possible to establish, from the mucus protein fraction, a set of potential biomarkers for each location in a total of 35 peaks, being 17 peaks specific to Caniçal located farm and 18 to Ribeira Brava. The proposed analytical approach revealed a useful strategy providing accurate and fast results for fish geographical origin discrimination.