Browsing by Author "Moreira, T."
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- Characterization of food from burnt areas in the Central Region of PortugalPublication . Gueifão, S.; Moreira, T.; Ventura, M.; Delgado, I.; Coelho, I.; Castanheira, I.AIM: Forest fires constitute an environmental problem with adverse and diversified impacts on atmospheric, terrestrial, and aquatic ecosystems, with economic and social repercussions, and a significant impact on flora. Fire mineralizes soil nutrients and returns plant-locked nutrients to the soil. Nutrients are lost from the ecosystem through the release of particulates and volatile compounds during the fire, and later through surface transport and leaching by rains1. Wildfires can play an important role in the environmental distribution of major and trace elements, including through their mobilization by fire-induced runoff and associated transport of soil and ash particles. Also, wildfires have been found to release and deposit contaminants on the soil surface, either directly by combustion of vegetation and mineralization of soil organic matter or indirectly through interactions of ashes. This fact can lead to the addition of potentially significant amounts of these elements in the soil and, thereby, can alter its chemical properties2. This study aims to evaluate the content of arsenic (As), cadmium (Cd) and chromium (Cr) in cabbage, potatoes, eggs and fruit samples cultivated in recently burnt areas. MATERIAL AND METHODS: A total of 24 pools composed of 3 samples each was analysed at three different harvest periods. Cabbage samples from burnt zones were compared with a designated control sample from a non-burnt zone. Analytical determinations were performed by Inductive Plasma Coupled Mass Spectrometry (ICP-MS). Previously, samples underwent a heating block acid digestion with a validated time and temperature program. Speciation analysis was carried out by High Performance Liquid Chromatography (HPLC) coupled to ICP-MS. Before analysis, samples were extracted using nitric acid. Analyses were performed in accordance with ISO 17025:2005. RESULTS: The concentrations of As in fruits and Cd in eggs were below the limit of quantification (2.2 µg/kg and 3.1 µg/kg, respectively). The variation of Cr content between matrices was as follows: fruits > eggs > cabbages > potatoes. On the other hand, As contents was verified as: cabbage > eggs > potatoes > fruit. Cabbage presented the highest Cd content, while eggs had the lowest values for this element. When compared to the control sample, the most pronounced rise was observed for As. Speciation studies show that the predominant arsenic species in cabbages are also the most toxic ones, that is, arsenite (As (III)) and arsenate (As (V)). CONCLUSIONS: The values of the inorganic elements present in this study are not yet properly legislated so it is important to performed studies able to support future legal references. Monitoring studies based on accredited methods are a powerful aid in assessing the risk exposure of affected populations.
- Tempeh as a substitute of meat proteinPublication . Serôdio, A.; Moreira, T.; Motta, C.; Oliveira, L.; Sousa, B.; Castanheira, I.According to the Portuguese Association of vegetarians, adherence to vegetarian diets, and conscience with a reduction of meat consumption is increasing in Portugal. This study aims to describe the tempeh’s protein and amino acid (aa) profile, including the impact of culinary procedures. The results will be then included on the National Food Composition Table increasing the available information in this alternative protein sources, before and after cooking. Twenty tempeh samples from six different brands and production sets, representing the varieties available for consumption in Portugal, were purchased in commercial surfaces. Each sample was analysed “raw” (as it is on the package) and after two culinary procedures, sauteed and stewed after been marinated overnight, both procedures were executed in triplicate. “Raw” and cooked samples were grouped in different pools, each one with 20 sub-samples. Each pool was analysed in triplicate for aa profile. Amino acid profile was determined by UPLC/PDA (Ultra performance liquid chromatography with photodiode array detector). After quantification of aas, the protein quality was evaluated, by the calculation of protein scores. Tempeh presents values of the sum of amino acids between 11.5g/100g in “raw”, 12.6g/100g in sauteed and 10.05g/100g in stewed samples. Glutamic acid was the aa that shows the highest value in all samples. Protein scores present values above 1 for all aa, except for leucine and sulfur aa (methionine and cysteine) that represent the limiting aa. Concerning sum of aa, values decrease significantly (p> 0.05), from salted to “raw” and stewed after marinated, respectively. The results demonstrate that the culinary method used on tempeh’s changes the protein content. The existence of limiting aa confirms that we are in the presence of a legume. Thus requires protein complementarity, a combination of cereals with legumes, to obtain all essential aa demanded in one meal. However, tempeh constitutes one valid alternative for vegetable protein choices. The presented study reveals the importance of the inclusion of these results in the Portuguese Food Composition Table.
- The phytochemical and bioactivity profiles of wild Calluna vulgaris L. flowersPublication . Rodrigues, F.; Moreira, T.; Pinto, D.; Pimentel, F.B.; Costa, A.; Nunes, M.A.; Albuquerque, T.G.; Costa, H.S.; Palmeira-de-Oliveira, A.; Oliveira, A.I.; Sut, S.; Dall'Acqua, S.; Oliveira, M.B.P.P.The nutritional composition of Calluna vulgaris flowers as well as the phytochemical profile, antioxidant (DPPH and FRAP assays), antimicrobial and cytotoxic (in human immortalized non-tumorigenic keratinocyte and fibroblasts) activities of aqueous, hydroalcoholic and ethanolic extracts were evaluated. A high content of fiber and carbohydrates (75%) and the prevalence of α-tocopherol as vitamer deserves attention. Linolenic (35%), linoleic (27%) and palmitic (21%) acids were the most abundant fatty acids. Qualitative and quantitative analysis by LC-MS and 1NMR indicated high levels of quercetin, kaempferol and myricetin derivatives as well as procyanidins. The hydro-alcoholic extract displayed the highest antioxidant activity and total phenolics (TPC) and flavonoid contents (TFC). No adverse effects on cells were observed until a concentration of 100 μg/mL and a good antimicrobial activity was reported against S. epidermidis and S. aureus with the hydro-alcoholic extract. The data obtained demonstrated that wild plants like heather, although not being a common nutritional reference, can be used in an alimentary base as a source of bioactive compounds, namely antioxidants.