Browsing by Author "Rodrigues, Sandra"
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- Advances in sheep and goat meat products researchPublication . Teixeira, Alfredo; Silva, Severiano; Rodrigues, SandraThe main goal of this chapter was to review the state of the art in the recent advances in sheep and goat meat products research. Research and innovation have been playing an important role in sheep and goat meat production and meat processing as well as food safety. Special emphasis will be placed on the imaging and spectroscopic methods for predicting body composition, carcass and meat quality. The physicochemical and sensory quality as well as food safety will be referenced to the new sheep and goat meat products. Finally, the future trends in sheep and goat meat products research will be pointed out.
- Análise dos efeitos da redução e substituição de NaCl na qualidade físico-química de chouriças de carne de porco bísaroPublication . Ferreira, Iasmin da Silva; Rodrigues, Sandra; Oliveira, Miguel; Pereira, Etelvina; Teixeira, AlfredoO objetivo deste estudo foi verificar o efeito da redução e substituição de NaCl na qualidade físico-química de chouriças de carne. Verificou-se que a referida substuição não alterou as características físico-químicas das chouriças de forma significativa
- Análise dos efeitos da redução e substituição de NaCl na qualidade físico-química de chouriças de carne de porco bísaroPublication . Ferreira, Iasmin da Silva; Rodrigues, Sandra; Oliveira, Miguel; Pereira, Etelvina; Teixeira, AlfredoO objetivo deste estudo foi verificar o efeito da redução e substituição de NaCl na qualidade físico-química de chouriças de carne. Verificou-se que a referida substuição não alterou as características físico-químicas das chouriças de forma significativa
- Análise exploratória sobre a qualidade sensorial da carne de cordeiros das raças Churra Galega Bragançana Branca (DOP) e Churra Galega Bragançana PretaPublication . Rodrigues, Sandra; Vasconcelos, Lia; Pereira, Etelvina; Carloto, Amândio; Teixeira, Alfredo; Sousa, Fernando Ruivo deO objetivo deste trabalho foi o conhecimento exploratório do perfil sensorial da carne de cordeiros das raças Churra Galega Bragançana Branca (CGBB) e Churra Galega Bragançana Preta (CGBP) e a averiguação da possibilidade em diferenciar do ponto de vista gustativo a carne das duas raças. Foram utilizadas amostras de perna, costeleta e lombo de cordeiros das 2 raças com 3 diferentes níveis de engorda. As diferenças foram avaliadas por um painel de provadores qualificado que realizou o método descritivo quantitativo e o teste triangular. Globalmente não se verificaram diferenças relevantes entre a carne de cordeiros de categorias diferentes relativamente às suas características sensoriais, em qualquer uma das raças. Na maioria dos atributos as avaliações médias localizaram-se na parte inferior da escala, indicando que a carne de cordeiro nas peças avaliadas é uma carne com odor e flavor pouco intensos, tenra, seca a medianamente suculenta, com mastigabilidade fácil, e persistência de flavor medianamente intensa. Os odores e flavores identificados estão relacionados com o que é característico a carne de cordeiro. A percepção de sabor/gosto adocicado estará relacionada com a tradição de consumo desta carne temperada, tempero do qual faz parte o sal. O teste triangular permitiu concluir que na prova de longissimus dorsi as duas raças são diferenciáveis, particularmente pela suculência, dureza, sabor e cor.
- Análise sensorial de produtos curados. Presunto e pá de porco Bísaro vs pernas curadas de ovinos e caprinosPublication . Rodrigues, Sandra; Paulos, Kátia; Fernandes, Aline; Pereira, Etelvina; Teixeira, AlfredoEm Portugal o consumo de ovinos e caprinos é particularmente sazonal, estando relacionado com épocas festivas do ano como a Páscoa e o Natal. Em Portugal, a carne de ovinos e caprinos mais apreciada e valorizada pelo consumidor, provém, na generalidade, de carcaças de animais muito jovens, ou seja; carcaças extremamente ligeiras, tendo como base da alimentação o leite materno, as quais são abatidos com cerca de 90 dias de idade. Contudo, a carne de animais mais velhos e mais pesados, ou mesmo de refugo não são muito apreciadas, sendo esse tipo de carne considerada mais apropriada para processar como produto seco, curado ou fumado. Para valorizar estes animais têm surgido vários estudos relacionados com o processamento da sua carne de modo a conferir-lhes características apreciadas (Beriain et al., 1997; Cosenza et al., 2003a; Cosenza et al., 2003b; Madruga e Bressan, 2011; Panea et al., 2011; Teixeira et al., 2011; Oliveira et al., 2014; Paulos et al., 2015; Leite et al., 2015; Tolentino et al., 2017; Ortega et al., 2016). No âmbito do Projeto de investigação BISOVICAP - Processamento de carnes de suíno, ovino e caprino, para a produção de novos produtos. Presunto e pâté - estudou-se uma estratégia de valorização da carne de animais com baixo valor comercial, das raças autóctones da região transmontana (Cabra Serrana e Ovelha Churra Galega Bragançana) fora das marcas de qualidade DOP e IGP, desenvolvendo um novo produto transformado através de um processo de salga e secagem (pernas curadas). Entre outras características, avaliou-se o efeito do processo de cura nas características sensoriais do produto. No projecto de investigação BISIPORC – Pork extensive production of Bísara breed, in two alternative systems: fattening on concentrate vs chesnut estudou-se, entre outras características a qualidade sensorial de um produto de excelencia o presunto, e também da pá, de porco Bisaro. Com este trabalho pretende-se verificar a existencia de diferenças significativas entre os novos produtos transformados de ovinos e caprinos e os muito apreciados presunto e pá de porco Bisaro no que respeita as suas características sensoriais.
- Anthocyanin profiles of Crataegus monogyna Jacq. fruits in different maturity stagesPublication . Barreira, João C.M.; Rodrigues, Sandra; Dueñas, Montserrat; Carvalho, Ana Maria; Santos-Buelga, Celestino; Ferreira, Isabel C.F.R.The vast structural diversity of natural compounds found in plants provides unique opportunities for discovering new drugs. Anthocyanins are an example of bioactive compounds with possible beneficial effects on human health (/). Crataegus monogyna Jacq. (hawthorn) has been extensively studied due to its various alleged health benefits (2) . Herein, samples from fruits on three different maturity stages (unripe, ripened and over ripened fruits) were extracted with acidified (trifluoracetic acid) methanol. Extracts were purified on a C1s SepPak® Vac 3 cc cartridge (Phenomenex) and filtered through a 0.22-pm disposable LC filter disk. The HPLC system consisted of a 1-lewlett-Packard 1100 chromatograph (Agilent Technologies) with a quaternary pump and a diode array detector (DAD) coupled to an HP Chem Station (rev. A.05.04) data-processing. Double detection was carried out by DAD, using 520 nm as the preferred wavelength, and MS detection, performed in an API 3200 Qtrap (Applied Biosystems) equipped with an ESI source and a triple quadrupole-ion trap mass analyzer that was controlled by the Analyst 5.1 software. Further details were given by Rodrigues et al. (3). The anthocyanin profiles obtained for ripened and over ripened fruits were quite similar, consisting of five different compounds, whereas the profile in unripe fruits was simpler (only two anthocyanins). Cyanidin 3-0-glucoside, pelargonidin 3-0-glucoside and peonidin 3-0-glucos ide were positively identified by comparison with standards. The p1·esence of cyanidin 3-0-rutinoside and cyanidin pentoside was also confirmed by comparison of its chromatographic and UV and mass spectral characteristics with data in our library. Cyanidin-3-0-glucoside was the major anthocyanin in all the samples, and over ripened th1its were, by far, the phenological stage with the highest anthocyanin concentrations, which was coherent with its higher pigmentation. Accordingly, C. manogyna might be considered as a potential natural source of anthocyanins, whose bioactive properties might have several applications.
- Antimicrobial activity, phenolic profile and role in the inflammation of propolisPublication . Silva, João; Rodrigues, Sandra; Feás, Xesús; Estevinho, Leticia M.Nowadays a great amount of information regarding chemical and biological aspects of bee products is available in the literature, but few data on its therapeutic uses are found. The aim of this study was to evaluate the phenolic profile, the in vitro antimicrobial activity and effect in the hyaluronidase enzyme (widely related with the inflammation process) of propolis harvested in Portugal. The efficacy of three extracts (hydro-alcoholic, methanolic and aqueous) was also compared. It was chosen the hydroalcoholic extract, because this was the most effective for extracting phenolic compounds. The antimicrobial activity was accessed in Gram-positive and Gram-negative bacteria and yeasts, isolated from different biological fluids and the results were then compared with the obtained for reference microorganisms. The propolis from Bragança was the one that possessed the highest polyphenols’ content. The sample from Beja showed the less significant inhibition of the hyaluronidase enzyme. Concerning the antimicrobial activity, Candida albicans was the most resistant and Staphylococcus aureus the most sensitive. The reference microorganisms were more sensitive than the ones isolated from biological fluids.
- An approach to predict chemical composition of goat Longissimus thoracis et lumborum muscle by Near Infrared Reflectance spectroscopyPublication . Teixeira, Alfredo; Oliveira, António Filipe Gomes de Faria; Paulos, Kátia; Leite, Ana; Marcia, Anabela; Amorim, André; Pereira, Etelvina; Silva, Severiano; Rodrigues, SandraThe ability of near infrared reflectance spectroscopy (NIRS) to estimate the protein, moisture, connective tissue and ash content in the Longissimus thoracis et lumborum (LTL) muscle of goat was studied. Samples (n=240) of the LTL muscle were taken from the 8th to 13th rib cut of goat carcasses. Samples were scanned in a FT-NIR Master™ N500 (BÜCHI) over a NIR spectral range of 4000-10,000cm < sup > -1 < /sup > with a resolution of 4cm < sup > -1 < /sup > . It was collected 3 spectra per sample and subsequently, chemical analyses were performed at the Carcass and Meat Quality Laboratory of ESA-IPB. Using NirCal 1.5 it was developed a PLS regression model assaying, first and second derivatives as math treatment and multiplicative scatter correction for minimizing scattering effect on the spectra database recorded (n=240). The best calibrations' models show relatively good predictability for protein (standard error of prediction SEP=0.43; coefficient of determination R < sup > 2 < /sup > =0.91), moisture (SEP=0.48; R < sup > 2 < /sup > =0.92). Calibrations' models obtained are important as a first attempt to predict the chemical composition of goat meat by NIRS. More experimental data are needed to improve the accuracy of these calibrations.
- Atributos sensoriales de lomo de cerdo Bísaro, alimentado con y sin castaña, vs. comercialPublication . Rodrigues, Sandra; Oliveira, I.; Vasconcelos, Lia; Pereira, Etelvina; Teixeira, Alfredo; Rodrigues S.This work aimed to evaluate the sensory characteristics of Bísaro pork loin fed with and without chestnut and commercial pork. Samples of each type of meat were duly identified and cooked in a con-ventional oven until it reached 80 °C in the thermal centre. Then, pieces of 2 cm side were cut, wrap-ped in aluminium foil and adequately codified. Each panellist analysed in two sessions a total of 6 samples of each type of meat. Results indicated that the panellists were able to distinguish the different types of meat, and the colour was the most discriminating attribute. The panellists identified the Bísaro pork loin fed with chestnut with the highest odour intensity and the Bísaro pork fed without chestnut with a less bright fat colour. The commercial pork loin had the lowest value of all the sensory attributes under study.
- Autenticidad de salchichas de carne de ovino y caprinoPublication . Leite, Ana; Rodrigues, Sandra; Paulos, Kátia; Oliveira, António Filipe Gomes de Faria; Pereira, Etelvina; Teixeira, AlfredoThe aim of this work was to contribute to the fabrication of a new of product, a fresh sausage based on meat from culled sheep and goat animals as a way to give added value to animals with very low marketing price. A total of 280 animals, 140 ewes and 140 goats were slaughtered, during seven months. The fabrication of sausages was carried out at a local industry and two samples of goat and sheep sausages were taken every month. Laboratory analyses of all parameters were made by triplicate. Concerning the fatty acids profile, it was checked that the main fatty acids (oleic acid (C18:1), palmitic acid (C16:0), stearic acid (C18:0) and linolenic acid (C18:2)), influenced the different fractions which characterize them (monounsaturated fatty acids (MUFA), saturated fatty acids (SFA) and polyunsaturated fatty acids (PUFA). Fatty acids profile could be also used as authentication tools for further monitoring and fraud detection in this kind of traditional food product.