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- Physicochemical fingerprint of "Pera Rocha do Oeste". A PDO pear native from PortugalPublication . Pedro, Soraia; Coelho, Elisabete; Peres, Maria de Fátima; Machado, Ana; Rodrigues, A.M.; Wessel, Dulcineia F.; Coimbra, Manuel A.; Anjos, O."Pera Rocha do Oeste" is a pear (Pyrus communis L.) variety native from Portugal with a Protected Designation of Origin (PDO). To supply the world market for almost all the year, the fruits are kept under controlled storage. This study aims to identify which classical physicochemical parameters (colour, total soluble solids (TSS), pH, acidity, ripening index, firmness, vitamin C, total phenols, protein, lipids, fibre, ash, other compounds including carbohydrates, and energy) could be fingerprint markers of PDO "Pera Rocha do Oeste". For this purpose, a data set constituting fruits from the same size, harvested from three orchards of the most representative PDO locations and stored in refrigerated conditions for 2 or 5 months at atmospheric conditions or for 5 months under a modified atmosphere, were selected. To validate the fingerprint parameters selected with the first set, an external data set was used with pears from five PDO orchards stored under different refrigerated conditions. Near infrared (NIR) spectroscopy was used as a complementary tool to assess the global variability of the samples. The lightness of the pulp; the b* CIELab coordinate of the pulp and peel; and the pulp TSS, pH, firmness, and total phenols, due to their lower variability, are proposed as fingerprint markers of this pear.
- PLS-R calibration models for wine spirit volatile phenols prediction by Near-Infrared SpectroscopyPublication . Anjos, O.; Caldeira, Ilda; Fernandes, Tiago A.; Pedro, Soraia; Vitória, Cláudia; Alves, Sheila Oliveira; Catarino, Sofia; Canas, SaraNear-infrared spectroscopic (NIR) technique was used, for the first time, to predict volatile phenols content, namely guaiacol, 4-methyl-guaiacol, eugenol, syringol, 4-methyl-syringol and 4- allyl-syringol, of aged wine spirits (AWS). This study aimed to develop calibration models for the volatile phenol’s quantification in AWS, by NIR, faster and without sample preparation. Partial least square regression (PLS-R) models were developed with NIR spectra in the near-IR region (12,500–4000 cm−1 ) and those obtained from GC-FID quantification after liquid-liquid extraction. In the PLS-R developed method, cross-validation with 50% of the samples along a validation test set with 50% of the remaining samples. The final calibration was performed with 100% of the data. PLS-R models with a good accuracy were obtained for guaiacol (r2 = 96.34; RPD = 5.23), 4-methyl-guaiacol (r2 = 96.1; RPD = 5.07), eugenol (r2 = 96.06; RPD = 5.04), syringol (r2 = 97.32; RPD = 6.11), 4-methylsyringol (r2 = 95.79; RPD = 4.88) and 4-allyl-syringol (r2 = 95.97; RPD = 4.98). These results reveal that NIR is a valuable technique for the quality control of wine spirits and to predict the volatile phenols content, which contributes to the sensory quality of the spirit beverages.
- FT-Raman methodology applied to identify different ageing stages of wine spiritsPublication . Anjos, O.; Caldeira, Ilda; Pedro, Soraia; Canas, SaraDuring the ageing process of wine spirits several phenomena occur, which are responsible for the final quality of the beverage. This work aimed to discriminate the aged wine spirits according to the wood species, ageing technology and ageing time using FT-Raman methodology. For this purpose, the same Lourinhã wine distillate aged in 250-L wooden barrels of Limousin oak wood (L) and chestnut wood (C) separately and used together (L + C), was monitored through FT-Raman during the first 12 months of ageing. This technique was also applied to the same wine distillate aged in stainless steel tanks with staves of the same kinds of wood and during the same period. FT-Raman allows separating the wine spirits according to the different wood species and ageing time. This technique seems to be a promising tool to monitor the ageing process of wine spirit through different technologies.
- Characterization of mineral composition and nutritional value of acacia green podsPublication . Pedro, Soraia; Antunes, Carlos Alberto Lopes; Monteiro, M.C.H. Carmo; Pitacas, F.I.; Gonçalves, Joana; Gominho, Jorge; Gallardo, Eugenia; Anjos, OThe Acacia genus is considered one of the most invasive taxa in some habitats, namely coastal dunes, maritime calcareous soils, fresh lands in the valleys, mountainous areas, and the banks of watercourses and roadsides. In Portugal, the severity risk is very high, so this study aimed to evaluate the nutritional and mineral contents of the green pods as a potential source for livestock feeds and soil fertilizer because, as far as we know, there is no use for this species. The seven different species of Acacia (Acacia mearnsii Link, Acacia longifolia (Andrews) Willd, Acacia melanoxylon R. Br., Acacia pycnantha Bentham, Acacia dealbata Link., Acacia retinodes Schlecht, and Acacia cyclops A. Cunn. ex G. Don fil) were evaluated. The results showed that Acacia green pods have a high protein, fibre and minerals content, especially in potassium (K), calcium (Ca) and magnesium (Mg). All species present a different profile of the studied parameters, suggesting different potentials for their future use. Near-infrared spectroscopy was a potential tool to predict the earlier quality of the Acacia green pods to better select the raw material for the different applications.
- Application of functional data analysis and FTIR-ATR spectroscopy to discriminate wine spirits ageing technologiesPublication . Anjos, O.; Martínez Comesaña, Miguel; Caldeira, Ilda; Pedro, Soraia; Eguía Oller, Pablo; Canas, SaraFourier transform infrared spectroscopy (FTIR) with Attenuated Total Reflection (ATR) combined with functional data analysis (FDA) was applied to differentiate aged wine spirits according to the ageing technology (traditional using 250 L wooden barrels versus alternative using micro-oxygenation and wood staves applied in 1000 L stainless steel tanks), the wood species used (chestnut and oak), and the ageing time (6, 12, and 18 months). For this purpose, several features of the wine spirits were examined: chromatic characteristics resulting from the CIELab method, total phenolic index, concentrations of furfural, ellagic acid, vanillin, and coniferaldehyde, and total content of low molecular weight phenolic compounds determined by HPLC. FDA applied to spectral data highlighted the differentiation between all groups of samples, confirming the differentiation observed with the analytical parameters measured. All samples in the test set were differentiated and correctly assigned to the aged wine spirits by FDA. The FTIR-ATR spectroscopy combined with FDA is a powerful methodology to discriminate wine spirits resulting from different ageing technologies.
- Vibrational spectroscopy applied to Arbutus unedo fruit spirit characterizationPublication . Antunes, Carlos Alberto Lopes; Caldeira, Ilda; Pedro, Soraia; Canas, Sara; Anjos, O.Arbutus unedo spirit (AUS) is a typical beverage of Mediterranean countries, which is usually produced without wood ageing. However, nowadays there is a trend related to the innovation and search for new market options related to this beverage. This work aimed to identify a technique to distinguish the AUS aged with different times and different toasting levels by an easier and cheaper way.
- Use of acacia pods as a source of vegetal organic matter for soilPublication . Pedro, Soraia; Antunes, Carlos Alberto Lopes; Pitacas, F.I.; Monteiro, M.C.H.; Gominho, Jorge; Gallardo, Eugenia; Anjos, O.Incorporating vegetal organic matter into the soil releases nutrients and increases its contents in organic matter, which can provide higher soil productivity and lower susceptibility to compaction. Acacia is an invasive plant in Portugal, and the huge seed bank incorporated into the soil every year is problematic for their dissemination. Suppose the green pods can have a sustainable use contributing to soil fertility. In that case, it will be possible to reduce this seed bank and contribute to delaying the proliferation of this species. In this work, the value, and mineral elements contents of Acacia pycnantha, A. retinodes and A. longifolia green pods were evaluated concerning their potential use as soil fertilizers.
- Desenvolvimento de iogurtes com polpa de figo-da-índiaPublication . Pedro, Soraia; Anjos, Ofélia Maria Serralha dos; Peres, Maria de Fátima Pratas; Rodrigues, AnaO figo-da-índia é constituído maioritariamente por água (84-90 %) e açúcares (10-15 %), predominantemente glucose e frutose. Além disso, devido ao seu conteúdo em proteínas, fibras, minerais, vitamina C, β-caroteno, niacina, riboflavina e tiamina, este fruto tem sido considerado com elevado interesse nutricional, bem como reportadas algumas atividades biológicas. Neste contexto e dado as propriedades sobejamente conhecidas dos benefícios do iogurte, pretendeu-se desenvolver um iogurte e uma gelatina de iogurte, com polpa de figo-da-índia. A polpa foi fornecida pela Associação do Figo da Índia da Beira Baixa (AFIBB) e os iogurtes foram desenvolvidos nos laboratórios da Schreiber Foods Portugal, S.A. Foram testadas várias formulações para o desenvolvimento dos iogurtes, tendo-se selecionado para produtos finais duas gelatinas de iogurte e dois iogurtes tipo grego: a) gelatina de iogurte 0 % de matéria gorda com 5 % de polpa de figo-da-índia e aroma de manga; b) gelatina de iogurte 0 % de matéria gorda com 2,5 % de polpa de figo-da-índia e preparado de ananás maracujá; c) iogurte tipo grego bicamada com 8 % de polpa de figo-da-índia; d) iogurte tipo grego batido com 8 % de polpa de figo-da-índia. Foram realizados estudos de tempo de vida nos iogurtes desenvolvidos ao longo de 52 dias, para os parâmetros pH, textura e força gel. As amostras foram analisadas no 1º, 3º, 7º, 15º, 23º, 30º, 40º e 52º dias após produção. Os resultados dos estudos de tempo de vida foram submetidos a uma análise de variância a dois fatores (tipo de iogurte e dias de armazenamento). Estes resultados indicam que existem diferenças significativas (p<0,05) para pH, textura e força gel entre os iogurtes. Os produtos finais foram submetidos a testes de aceitabilidade e obteve-se uma avaliação positiva para os 4 produtos desenvolvidos. A gelatina de iogurte de figo-da-índia com aroma de manga e o iogurte grego de figo-da-índia em bicamada foram os mais apreciados. Com base nos parâmetros físico-químicos, o tempo de vida estimado para os produtos desenvolvidos foi de 35 dias.
- PLS-R calibration models for wine spirit volatile phenols prediction by Near-Infrared SpectroscopyPublication . Anjos, O.; Caldeira, Ilda; Fernandes, Tiago A.; Pedro, Soraia; Vitória, Cláudia; Alves, Sheila Oliveira; Catarino, Sofia; Canas, SaraNear-infrared spectroscopic (NIR) technique was used, for the first time, to predict volatile phenols content, namely guaiacol, 4-methyl-guaiacol, eugenol, syringol, 4-methyl-syringol and 4-allyl-syringol, of aged wine spirits (AWS). This study aimed to develop calibration models for the volatile phenol’s quantification in AWS, by NIR, faster and without sample preparation. Partial least square regression (PLS-R) models were developed with NIR spectra in the near-IR region (12,500–4000 cm1) and those obtained from GC-FID quantification after liquid-liquid extraction. In the PLS-R developed method, cross-validation with 50% of the samples along a validation test set with 50% of the remaining samples. The final calibration was performed with 100% of the data. PLS-R models with a good accuracy were obtained for guaiacol (r2 = 96.34; RPD = 5.23), 4-methyl-guaiacol (r2 = 96.1; RPD = 5.07), eugenol (r2 = 96.06; RPD = 5.04), syringol (r2 = 97.32; RPD = 6.11), 4-methylsyringol (r2 = 95.79; RPD = 4.88) and 4-allyl-syringol (r2 = 95.97; RPD = 4.98). These results reveal that NIR is a valuable technique for the quality control of wine spirits and to predict the volatile phenols content, which contributes to the sensory quality of the spirit beverages.
- Casting light on the chemical characterization of acacia podsPublication . Pedro, Soraia; Fernandes, Tiago A.; Antunes, Alexandra M.M.; Gominho, Jorge; Gallardo, Eugenia; Anjos, O.Invasive species impose a strain on natural ecosystems by contributing to the loss of certain native species. Acacia species are amongst the most aggressive invasive species in Portugal. In this work, Acacia retinodes, A. longifolia, A. melanoxylon, A. pycnantha and A. dealbata pods were studied concerning the extraction of compounds for potential industrial application.