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- Non-destructive imaging and spectroscopic techniques for assessment of carcass and meat quality in sheep and goats: a reviewPublication . Silva, Severiano; Guedes, Cristina M.; Rodrigues, Sandra; Teixeira, AlfredoIn the last decade, there has been a significant development in rapid, non-destructive and non-invasive techniques to evaluate carcass composition and meat quality of meat species. This article aims to review the recent technological advances of non-destructive and non-invasive techniques to provide objective data to evaluate carcass composition and quality traits of sheep and goat meat. We highlight imaging and spectroscopy techniques and practical aspects, such as accuracy, reliability, cost, portability, speed and ease of use. For the imaging techniques, recent improvements in the use of dual-energy X-ray absorptiometry, computed tomography and magnetic resonance imaging to assess sheep and goat carcass and meat quality will be addressed. Optical technologies are gaining importance for monitoring and evaluating the quality and safety of carcasses and meat and, among them, those that deserve more attention are visible and infrared reflectance spectroscopy, hyperspectral imagery and Raman spectroscopy. In this work, advances in research involving these techniques in their application to sheep and goats are presented and discussed. In recent years, there has been substantial investment and research in fast, non-destructive and easy-to-use technology to raise the standards of quality and food safety in all stages of sheep and goat meat production. © 2020 by the authors.
- Pork meat quality of Preto Alentejano and commercial largewhite landrace crossPublication . Teixeira, Alfredo; Rodrigues, SandraThis work aimed to evaluate the physical-chemical characteristics of pork from a local breed (Portuguese black pork called Preto Alentejano) and a commercial breed. Sixteen animals were used, 4 females and 4 males from each breed. Animals had 80-100 kg of live weight. The longissimus muscle between the 5th thoracic vertebra and the 10th lumbar vertebra was used in the analysis. Samples were analysed for protein, fat, pigments, ashes, dry mater, water-holding capacity, and texture. Results of fat and pigments contents indicate significant (P<0.05 and P<0.01) differences for all treatments. For protein, ashes, dry mater, water-holding capacity and texture, no significant differences were found for sex. In the analysis of fatty acids composition, ten were detected, being the main ones C16:0, C18:0, C16:1, C18:1, C18:2. There was a predominance of monounsaturated fatty acids (MUFA), followed by saturated (SFA) and polyunsaturated (PUFA). Differences were significant for sex (P<0.01) and breed (P<0.01). Preto Alentejano breed and females presented the higher percentages of SFA (P<0.01) and MUFA (P<0.001) fatty acids. Differences between breeds might be due to breed production system and feed differences.
- Melhoramentos nas instalações de caprinos de leite no Nordeste Transmontano visando o desenvolvimento da actividade e da fileira produtivaPublication . Barbosa, José Carlos; Teixeira, AlfredoDairy goats in the northeast of Trás-os-Montes, are mainly from Serrana breed, raised in extensive systems, according to traditional farming systems. The flock rangeland through the territory, and are not given any indoor supplementation in the shelters where they spend the night. Flocks are small, but they are the economic support of many families in a less-favoured region. Shelters and farm buildings are very elementary and goats are hand milked in the places where they are housed during the night. In order to improve milking conditions, the physical conditions of the places where milking is carried out must be improved. However, introducing changes is not easy, since there is some resistance among breeders when it comes to the adoption of new techniques, which may be due to their mistrust and lack of knowledge concerning these techniques. So, bearing in mind farmers´ socioeconomic conditions, we have designed demonstration tasks to encourage the adoption of innovative methods which may enable better milking conditions in the northeast of Trás-os-Montes. Na região do Nordeste Transmontano, os rebanhos de cabras para produção de leite são, maioritariamente, compostas por animais da raça Serrana. Estas cabradas são exploradas em sistema extensivo, tendo por base o pastoreio de percurso, praticamente sem recurso a suplementação alimentar. São rebanhos de pequena dimensão e a quantidade de leite produzido, por animal e por rebanho, é baixa. As instalações usadas para o maneio e alojamento dos animais são, muitas vezes, rudimentares. Um trabalho de estudo e análise das instalações utilizadas pelos criadores permitiu identificar os principais constrangimentos e problemas que devem ser ultrapassados para o desenvolvimento desta actividade, destacando-se os aspectos relacionados com as condições de realização da ordenha. Para melhorar as condições de realização da ordenha é necessária a introdução de novas técnicas e tecnologias. No entanto, a sua adopção está dificultada pelo desconhecimento generalizado dos produtores sobre as soluções e opções de instalações e equipamentos a adoptar; e pela desconfiança e insegurança quanto ao funcionamento, adaptação e aumento de custos inerentes à introdução de novas técnicas e tecnologias. Assim, foram planificadas acções de desenvolvimento/demonstração, com diversas fases de intervenção quanto às instalações e equipamentos, tendo em consideração as condições e dificuldades socio-económicas dos produtores de cabras do Nordeste Transmontano. O resultado das acções já realizadas permite verificar que uma estratégia planificada por objectivos parcelares; com uma forte componente de demonstração em explorações de criadores locais, pode ter bons resultados na adopção de novas técnicas e tecnologias de ordenha; e na melhoria das instalações e equipamentos, tendo em vista a melhoria das condições de realização da ordenha, da qualidade do leite produzido e, consequentemente, da matéria prima para produção de queijo.
- Crescimento e desenvolvimento testicular dos borregos da raça Churra Galega BragançanaPublication . Valentim, Ramiro; Azevedo, Jorge; Teixeira, Alfredo; Correia, Teresa Montenegro; Almeida, José CarlosNo presente trabalho procurou-se estudar o crescimento testicular dos borregos da raça Churra Galega Bragançana, durante o processo de estabelecimento da puberdade fisiológica. Considerou-se que os borregos tinham atingido a puberdade fisiológica, quando ejacularam os primeiros espermatozóides. Um grupo de 15 borregos desta raça, pertencentes ao rebanho experimental da Escola Superior Agrária de Bragança (ESAB), nascidos de parto simples, durante a Primavera, foram utilizados na elaboração deste estudo. Quando se iniciou o presente trabalho, as aderências penianas dos borregos da raça Churra Galega Bragançana, então com idades compreendidas entre os 109 e os 133 dias, já haviam desaparecido. Nos borregos em estudo, os primeiros espermatozóides surgiram no ejaculado, em média, 183 dias após o nascimento, altura em que estes apresentavam um peso médio de 33,8 kg, ou seja, cerca de 45% do seu peso adulto. Nesta altura, o perímetro escrotal médio dos borregos era de 24,0 cm, o comprimento testicular de 9,4 cm, o diâmetro testicular de 4,9 cm e o volume escrotal de 81,3 cm3. Ao longo de todo o estudo, o crescimento dos testículos processou-se sempre dum modo bastante simétrico. Depois do estabelecimento da puberdade fisiológica, o peso corporal dos borregos passou a estar mais correlacionado com a idade cronológica. Se durante o período pré-puberdade fisiológica, o perímetro escrotal variou mais em função da idade e o volume escrotal e o comprimento e o diâmetro testiculares variaram mais em função do peso, depois do aparecimento da puberdade fisiológica, ambas as medidas escrotais passaram a variar mais em função da idade, enquanto que o oposto ocorreu com as medidas testiculares.
- Estudos de avaliação da qualidade e da composição de carcaças de de ovinos das raças Churras Bragançana, Mondegueira e da Terra QuentePublication . Teixeira, Alfredo; Azevedo, JorgeDo grupo étnico Churro de ovinos, do Norte do País, foram escolhidas as raças mais representativas (Churra Galega Bragançana, Churra Mondegueira e Churra da Terra Quente), bem como alguns cruzados (Bragançana com Milchschaf, Bragançana e Mondegueira com Merina Precoce, Bragançana com Suffolk, Bragançana x Milchschaf com Merina Precoce e Churra da Terra Quente com Scottish Blackface) para base de vários estudos de avaliação da qualidade de carcaças, além de outros parâmetros produtivos.
- Subjective measurements of fat cover and kidney knob and channel fat for predicting shoulder, neck and flank plus breast tissue composition of Blanca Celtibérica kids.Publication . Delfa, Rafael; Joy, Margalida; Panea, Begoña; Jiménez Badillo, M.R.; Teixeira, AlfredoCCW, the assess of FC on two scores (1-5) and (1-15) and the assess of KKCF amount on two scores (1-3) and (1-9) were used as predictors of shoulder, neck and flank plus breast tissue composition of 31 Blanca Celtibérica kids, with an average CCW of 6,9± 2,1 Kg. Proportionately 97, 91 and 92% of the variation in muscle weight of shoulder, neck and flank plus breast, respectively were accounted for by variation in CCW. The variation in CCW also explained 96, 49 and 86% of the variation of shoulder, neck and flank plus breast bone tissue composition. The inclusion in the prediction equation for neck bone weight of FC (1-15), increase the precision in 7% and reduced the RSD in 5,7%. Finally the variation in CCW and FC (1-15) explained 87, 76 and 90% of the variation in fat weight of shoulder, neck and flank plus breast, respectively. Nevertheless the inclusion of KKCF amount (1-3) in the prediction equations of fat weight of shoulder and flank plus breast increase the precision in 2% and reduced the RSD in 6,1 and 10,2%, respectively. El peso canal fría, grado de engrasamiento con dos escalas de (1-5) y de (1-15) puntos y cantidad de grasa pélvico renal con dos escalas de puntuación (1-3) y (1-9) fueron utilizados como predictores de la composición tisular de la espalda, cuello y bajos de 31 cabritos de raza Blanca Celtibérica, con una media de peso canal fría de 6,9± 2,1 Kg. La variación del peso canal fría explicó el 97, 91 y 92% de la variación en el peso del músculo de la espalda, cuello y bajos respectivamente. Así mismo, la variación del peso canal fría explicó el 96, 49 y 86% de la variación en el peso del hueso de las mismas piezas y en el mismo orden. No obstante la entrada en la ecuación de predicción del peso del hueso del cuello, del engrasamiento (1-15) mejoró la precisión de la estimación en 7 puntos porcentuales, con una reducción del RSD asociado del 5,7%. Finalmente la variación del peso canal fría y engrasamiento (1-15) explicó el 87, 76 y 90% de la variación en el peso de la grasa total de la espalda, cuello y bajos. No obstante la entrada en la ecuación de predicción de la cantidad de grasa pélvico renal (1-3), mejoró la precisión de la estimación de la variación del peso de la grasa total de la espalda y bajos en un 2%, con una reducción del RSD asociado de un 6,1 y 10,2% respectivamente.
- Edible mushrooms as a natural source of food ingredient/additive replacerPublication . Rangel-Vargas, Esmeralda; Rodriguez, Jose Antonio; Domínguez, Rubén; Lorenzo Rodriguez, Jose Manuel; Sosa-Morales, María Elena; Andrés, Silvina Cecilia; Rosmini, Marcelo; Pérez-Álvarez, José Ángel; Teixeira, Alfredo; Santos, Eva MaríaAlthough mushrooms have been exploited since ancient times because of their particular taste and therapeutic properties, the interest in edible species as a source of ingredients and bioactive compounds is recent. Their valuable nutritional contents in protein, dietary fiber and bioactive compounds make them ideal candidates for use in foods in efforts to improve their nutritional profiles. This trend is in line with the consumer’s growing demand for more plant-based foods. The present review paper explores different studies focused on the use of common edible mushrooms as an ingredient and additive replacer by using them in fresh, dried, or even extract forms, as meat, fat, flour, salt, phosphates, and antioxidant replacers. The replacement of meat, fat, flour, and salt by mushrooms from commercial species has been successful despite sensorial and textural parameters can be affected. Moderate concentrations of mushrooms, especially in powder form, should be considered, particularly in non-familiarized consumers. In the case of antioxidant and antimicrobial properties, results are variable, and more studies are necessary to determine the chemical aspects involved.
- How does the added fat source affect sensory quality of sheep and goat pâtés?Publication . Rodrigues, Sandra; Almeida, Samanta Kelli; Pereira, Etelvina; Teixeira, AlfredoSensory quality of sheep and goat pâtés with different sources and percentage of fat (10% or 30%, and pork belly or olive oil) were evaluated. A trained taste panel performed sensory analysis and consumers were consulted to perceive their preferences. Generalised Procrustes Analysis was used to test the differences found by panellists. Panellists were able to find sensory differences between sheep and goat pâtés, and also fat percentages. Goat pâtés had higher values of juiciness and sheep pâtés had higher values of taste intensity. Ten percent pork belly fat pâtés had the highest values of colour and cohesiveness attributes and also aroma intensity, while 30% olive oil pâtés had the highest values of texture attributes, except cohesiveness. Although, differences between pâtés were found by panellists, consumers had no particular preference for one of them.
- A note on the use of a lumbar joint as a predictor of body fat depots in Aragonesa ewes with different body confition scoresPublication . Delfa, Rafael; Teixeira, Alfredo; Colomer-Rocher, F.The lumbar joint, which is handled to assess body condition scores, was taken from 52 adult Rasa Aragonesa ewes with body condition scores between 1·5 and 4·5 and dissected into muscle, bone, subcutaneous and intermuscular fat. The subcutaneous fat in the lumbar joint was highly correlated with total fat in the body (r=0·97), confirming the value of this region for assessing body condition in Rasa Aragonesa ewes.
- In vivo estimation of goat carcass composition and body fat partition by real-time ultrasonographyPublication . Teixeira, Alfredo; Joy, Margalida; Delfa, RafaelThe accuracy of ultrasound measurements to assess goat carcass composition and the partition of body fat depots was evaluated. An ultrasound machine with a 5-MHz probe and image analysis was used to assess in vivo fat thickness and muscle depth in 56 Spanish Celtiberica adult goats, in lumbar and breast body regions. The goats were slaughtered and the weight of body fat depots recorded. Measurements corresponding to the in vivo ultrasound fat thickness and muscle depth were taken on carcasses. The left sides of carcasses were completely dissected into their components. The best relationships (r = 0.94, P < 0.01) between in vivo and carcass measurements of fat thickness were obtained when measurements were taken at the sternum, and the best anatomical point was located between the third and fourth sternebrae. The best correlation coefficients (r = 0.84) for muscle depth were found for measurements taken between the third and the fourth lumbar vertebrae at 2 cm from the middle of the vertebral column. Body weight and ultrasound measurements were used to fit the best multiple regression equations to predict carcass composition and the partition of body fat depots. All equations, with the exception of those for muscle quantity, omental, and total body fat depot amounts, were computed after performing a logarithmic transformation. Body weight in association with the ultrasound measurement taken at largest LM muscle depth, between the first and second lumbar vertebrae accounted for 90% of the muscle weight. Body weight was the first variable admitted into the prediction models of muscle, mesenteric fat, and total body fat and accounted for 82, 67, and 79% of the variation in tissue weights, respectively. The ultrasound measurement of fat thickness taken at the third sternebra was the first variable admitted into the prediction models for intermuscular fat, kidney and pelvic fat, and total carcass fat and accounted for by 73, 75, 71, and 79% of the variation in the weight of these fat depots, respectively. The ultrasound measurements taken in the breast region, particularly at the third and fourth sternebrae, were the most suitable for assessing fat thickness. The results of this experiment suggest that BW associated with some in vivo ultrasonic fat measurements allow the accurate prediction of goat carcass composition and body fat depots.