Browsing by Author "Pereira, Regina"
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- 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.
- 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.
- Geographical differentiation of apple ciders based on volatile fingerprintPublication . Sousa, António; Vareda, José; Pereira, Regina; Silva, Catarina; Câmara, José S.; Perestrelo, RosaWith the globalization of food trade, it’s traceability and genuineness becomes increasingly more difficult. Therefore, it is necessary to develop analytical tools to define the authenticity and genuineness of food-derived products. In the current work, headspace solid-phase microextraction followed by gas chromatography-mass spectrometry (HS-SPME/GC–MS) combined with chemometric tools was used to establish the volatile fingerprint of apple ciders produced in different geographical regions of Madeira Island, in order to define their typicity and to identify putative geographical markers. A total of 143 volatile organic compounds (VOCs) belonging to dif ferent chemical families have been identified, of which 28 were found in all apple ciders independently of geographical region. Esters, terpenic and furanic compounds presented on average a higher contribution for the total volatile fingerprint in cider produced in northern region of the Island, whereas alcohols, acids, volatile phenols, carbonyl compounds and lactones in cider from southern region. Considering the relative areas of the VOCs, 43 revealed statistically significant differences (p < 0.001) between geographical regions, and 11 be tween northern and southern regions. A clear differentiation among cider-producing regions was observed on the developed partial least squares-discriminant analysis (PLS-DA) model. Two alcohols (1-hexanol, 1-octanol), 6 esters (methyl acetate, (Z)-3-hexen-1-ol acetate, ethyl hexanoate, ethyl nonanote, ethyl octanoate, isoamyl oc tanoate) and 1 terpenic compound (limonene), can be considered putative geographic markers due to their discriminatory ability. The results obtained recognize the specific and typical geographical characteristics of the cider, which will allow the forthcoming guarantee for the construction of a sustainable platform for the es tablishment of the authenticity and typicality of the regional cider.
- 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.