Browsing by Author "Delgado, Teresa"
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- Application of GC-MS to characterize the volatile composition of fruit distillates made with honeyPublication . Delgado, Teresa; Caldeira, Ilda; Anjos, O.Application of GC-MS to characterize the volatile composition of fruit distillates made with honey.
- Avaliação da robustez de modelos derivativos PLS-R em espectroscopia usando o número de pontos da suavização espectralPublication . Delgado, Teresa; Santos, António J.; Caldeira, Ilda; Anjos, O.Avaliação da robustez de modelos derivativos PLS-R em espectroscopia usando o número de pontos da suavização espectral.
- Bee pollen as a natural antioxidant source to prevent lipid oxidation in black puddingPublication . Anjos, Ofélia; Fernandes, Rodrigo Adérito Basílio; Cardoso, Susana M.; Delgado, Teresa; Farinha, Nelson; Paula, Vanessa Branco; Estevinho, Letícia M.; Carpes, Solange T.The antioxidant activity of bee pollen (mainly composed by Cistus ladanifer pellets) was explored in the context of black pudding production. For this purpose, three black pudding formulations comprising varying antioxidant compounds (sodium ascorbate, bee pollen and bee pollen extract) were produced. Bee pollen was characterized according to the botanical origin, antioxidant activity, total phenol and flavonoid contents and phenolic profile. Black pudding was characterized by the microbiological safety, lipid oxidation, pH, water activity and humidity at 1, 10, 21, 30 and 37 days. Sensory acceptance was evaluated on the four first periods of storage. Salmonella spp., Escherichia coli and Listeria monocytogenes were absent in all samples. Small variations on humidity and pH were observed during the black pudding's storage. Regarding lipid oxidation, it increased, on average, from 1.36 mg to 2.11 mg malondialdehyde/kg meat. Differences among the three formulations were only significant on the first days of storage. The sensory assessment did not differ between products. This study suggests that bee pollen may be used as a natural antioxidant in meat products, yet a careful labelling is essential to alert allergic consumers.
- Development of blueberry liquor: influence of distillate, sweetener and fruit quantity.Publication . Caldeira, Ilda; Lopes, Daniel; Delgado, Teresa; Canas, Sara; Anjos, O.In this work different formulations of blueberry liquor were tested and characterised based on their physico-chemical and sensory characteristics.
- Discrimination of aging wines with alternative oak products and micro-oxygenation by FTIR-ATRPublication . Sánchez-Gómez, R.; Anjos, O.; Nevares, I.; Delgado, Teresa; Alamo-Sanza, M. delThe use of alternative oak wood products (AOP), such as chips, cubes and staves, among other, from different geographical origins is a common practice for wine aging, where the micro-oxygenation (MOX, adding small doses of oxygen constantly over time) is essential to obtain a final wine more stable in time and with similar characteristics of barrel-aged wine. The aim of this work was to identify if spectroscopic techniques allow to discriminate wines aged with alternative oak products (chips and staves) from different oak woods (American, French and Spanish) and a floating micro-oxygenation (20 µg·L−1) after 10 years of bottling and compared to those aged in barrels. The spectral information and analysis were performed in a FTIR-ATR, with 128 scans per spectrum at a spectral resolution of 8 cm-1 in the wavenumber range from 4,000 to 450 cm-1. Principal component analyses of spectral information were performed using the Unscrambler® X. The results indicate that with this technique it is possible to clearly separate the wines aged by the three systems (chips, staves and barrels) in the case of American oak. In the case of French oak, wines aged in chips were clearly differentiated from wines aged in staves with those aged in barrels between the two. It is also possible to clearly separate aged wines with different Spanish oak systems. The application of FTIR-ATR appears to be a powerful technique for discriminating the quality of wines aged by different AOPs and wood barrels from different geographical origins.
- Enzyme inhibitory potential of Ligustrum lucidum Aiton berriesPublication . Paula, Vanessa Branco; Delgado, Teresa; Campos, Maria da Graça; Anjos, O.; Estevinho, Letícia M.Ligustrum lucidum Aiton and its berries have been used in Chinese traditional medicine for around two thousand years. In the present study, L. lucidium berries harvested in two regions of Portugal were studied. Haemolytic activity and inhibition of oxidative haemolysis as well as the enzyme inhibitory activities (α-amylase enzyme and acetylcholinesterase) were assessed. Results suggest that the different biological activities varied according to the region where samples were collected. Results demonstrated that the sample obtained from region R1 was the most efficient extract for all parameters evaluated, presenting the lowest values of IC50, 10.67 ± 0.46 μg/mL for the inhibition of erythrocyte oxidative haemolysis, 58.28 ± 3.77 μg/mL for the α-amylase enzyme and 67.67 ± 2.10 μg/mL for the acetylcholinesterase inhibition. L. Lucidum berries may be an interesting source of compounds for use in the development of the therapeutic armamentarium for diseases where enzymatic disruption is believed to play a role
- Extractive method optimization for Ligustrum lucidum yhat leads to a better free radical scavenging activityPublication . Delgado, Teresa; Campos, Maria da Graça; Farinha, Nelson; Estevinho, Letícia M.; Anjos, O.Ligustrum lucidum Aiton is a plant with important biological properties and its berries are used in Chinese medicine with tonic effects, used as a protection against some diseases due to the presence of antioxidants [1]. No research has been done in Portuguese samples and the aim of this work was to optimize the extraction process that gives the best antioxidant activity for L. lucidum berries from two different regions in Portugal (Region 1: Lisbon and Region 2: Castelo Branco).
- HPLC/DAD fingerprint of standardize extracts from Ligustrum lucidum Aiton berries, for bioactive activity screening.Publication . Delgado, Teresa; Paula, Vanessa Branco; Campos, Maria da Graça; Farinha, Nelson; Caeiro, André; Estevinho, Letícia M.; Anjos, O.HPLC/DAD fingerprint of standardize extracts from Ligustrum lucidum Aiton berries, for bioactive activity screening.
- Influence of raw-material in the fruit liquor preparationPublication . Anjos, O.; Lopes, Daniel; Delgado, Teresa; Canas, Sara; Caldeira, Ilda
- Influence of the storage conditions on the quality of bee pollenPublication . Anjos, O.; Paula, Vanessa Branco; Delgado, Teresa; Estevinho, Letícia M.Bee pollen is a healthful food product with a good nutritional profile and therapeutic properties. However, the storage conditions may affect its composition and characteristics. This study aimed to evaluate the effect of the storage conditions on chemical composition of different monofloral bee pollen samples, namely acidity (pH), water activity, total acidity and the content of fibre, ash, reducing sugars, protein, lipids, total phenols and total flavonoids. Nine bee pollen samples were harvested in three places in the Northeast of Portugal and divided into two aliquots: one was frozen at −20°C, while the other was dried at 42°C, until reaching moisture of 6–8%. Even though differences in the botanical origin are a significant factor explaining the variation between samples, the storage method was also found to be a highly significant factor for several parameters: reducing sugars, lipids, total phenols and total flavonoids. Higher counts were obtained on the frozen bee pollen samples regarding aerobic mesophiles and moulds and yeasts. Even so, for all samples and conservation methods, the values were below those given by the standards. Our study suggests that it is better to consume bee pollen frozen at −20°C in comparison to that dried in an electric oven.