Publicaciones de la categoría: Revistas científicas

Colour variability of beef in young bulls from fifteen European breeds

The objective of this study was to determine the variation of the colour of longissimus thoracis muscle within and among fifteen European cattle breeds reared under comparable management conditions. A total of 436 unrelated purebred young bulls from fifteen European breeds (Aberdeen Angus, Highland,
Jersey, South Devon, Danish Red, Holstein, Simmental, Asturiana de las Monta~nas (also known as Casina), Asturiana de los Valles, Avileña-Negra Iberica, Pirenaica, Marchigiana, Piemontese, Charolais and Limousin) were reared in five experimental research centres in the United Kingdom, Denmark, Spain, Italy and France. The pH of M. longissimus thoracis was measured at 24 h and after 10 days of ageing and colour at 48 h and 10 days. Two generalised linear models, Pearson correlations and a hierarchical cluster analyses were carried out. Lean meat colour differed significantly between breeds, and these fifteen European breeds could be grouped according to four classes of commercial interest: ‘very bright and pale-red’, ‘bright and pale’, ‘red’ and ‘dark and dull red’. These groups were partially related to body size and carcass traits, fatness and muscle development and structure, and were controlled by differences in gene expression within each breed.

 

Int J. food Scie and Techn, en prensa

 

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Effects of breed-production system on collagen, textural and sensory traits of 10 European beef cattle breeds

In the current study the collagen, texture and sensory characteristics of meat from 712 yearling males of 10 local Spanish and French beef breeds raised in their typical production systems were described. The breed-production system affected collagen and texture variables but affected sensory variables only slightly. There was a large amount of intra-breed-production system variation for all the  variables. French breeds had lower values for collagen solubility (approximately 12%) than Spanish breeds (approximately 40%). Stress (WB) varied from 36 N/cm2 in Casina to 44 N/cm2 in Salers, whereas compression stress at 80% ranged from 35N/cm2 in Asturiana de los Valles to 40 N/cm2 in Salers. Oven cooking resulted in higher cookinglosses (24%) than cooking on a grill (12%). Cooking losses increased as the grill temperatureincreased. Numerous significant correlations were found among variables. Carcass weight is associated with all the collagen and texture variables. Correlation coefficients among texture and collagen variables were statistically significant and these correlation coefficients were in general higher for solubility percentage than for total collagen content, highlighting the importance of the solubility of collagen rather than total collagen in determining meat textural properties.

 

JTS, en prensa

Consumer visual appraisal and shelf life of leg chops fromsuckling kids raised with natural milk or milk replacer

BACKGROUND: The use of milk replacers to feed suckling kids could affect the shelf life and appearance of themeat. Leg chops were evaluated by consumers and the instrumental colorwas measured. A machine learning algorithmwas used to relate them. The aim of this experimentwas to study the shelf life of the meat of kids reared with dam’smilk or milk replacers and to ascertain which illuminant and instrumental color variables are used by consumers as criteria to evaluate that visual appraisal.

RESULTS: Meat from kids reared with milk replacers was more valuable and had a longer shelf life than meat from kids reared with natural milk. Consumers used the color of the whole surface of the leg chop to assess the appearance of meat. Lightness and hue angle were the prime cues used to evaluate the  appearance of meat.

CONCLUSION: Illuminant D65 was more useful for relating the visual appraisal with the instrumental color using a machine learning algorithm. The machine learning algorithms showed that the underlying rules used by consumers to evaluate the appearance of suckling kid meat are not at all linear and can be  computationally schematized into a simple algorithm.

J Science Food Agriculture 98(7) 2651-2657

Consumer Perception of the Quality of Lamb and Lamb Confit

The patterns of food consumption in general and those of meat, in particular, are constantly changing. These changes are due not only to socioeconomic and cultural trends that affect the whole society but also to the specific lifestyles of consumer groups. Due to the importance of consumer lifestyle, the objectives of this study were (i) to identify the profiles of lamb meat consumers according to their orientation toward convenience, as defined by their eating and cooking habits; (ii) to characterize these profiles according to their socioeconomic characteristics and their preferences
regarding the intrinsic and extrinsic quality signals of lamb meat; and (iii) to analyze the willingness to pay for lamb confit. In this study, four types of consumers have been differentiated according to their lifestyles related to lamb consumption. These groups, due to their characteristics, could be called
“Gourmet”, “Disinterested”, “Conservative”, and “Basic”. The Gourmet group has characteristics that make it especially interesting to market a product such as lamb confit. However, this group is unaware of this product. Therefore, a possible strategy to expand the commercialization of light lamb and the confit product would be guided marketing to this niche market.

 

Foods, 7(5), 80

Consumer visual appraisal and shelf life of leg chops fromsuckling kids raised with natural milk or milk replacer

The use of milk replacers to feed suckling kids could affect the shelf life and appearance of themeat. Leg chops were evaluated by consumers and the instrumental colorwas measured. A machine learning algorithmwas used to relate them. The aim of this experimentwas to study the shelf life of the meat of kids reared with dam’smilk or milk replacers and to ascertain which illuminant and instrumental color variables are used by consumers as criteria to evaluate that visual appraisal.

RESULTS: Meat from kids reared with milk replacers was more valuable and had a longer shelf life than meat from kids reared with natural milk. Consumers used the color of the whole surface of the leg chop to assess the appearance of meat. Lightness and hue angle were the prime cues used to evaluate the appearance of meat.

CONCLUSION: Illuminant D65 was more useful for relating the visual appraisal with the instrumental color using a machine learning algorithm. The machine learning algorithms showed that the underlying rules used by consumers to evaluate the appearance of suckling kid meat are not at all linear and can be computationally schematized into a simple algorithm.

Consumer Perception of the Quality of Lamb and Lamb Confit

The patterns of food consumption in general and those of meat, in particular, are constantly changing. These changes are due not only to socioeconomic and cultural trends that affect the whole society but also to the specific lifestyles of consumer groups. Due to the importance of consumer lifestyle, the objectives of this study were (i) to identify the profiles of lamb meat consumers according to their orientation toward convenience, as defined by their eating and cooking habits; (ii) to characterize these profiles according to their socioeconomic characteristics and their preferences
regarding the intrinsic and extrinsic quality signals of lamb meat; and (iii) to analyze the willingness to pay for lamb confit. In this study, four types of consumers have been differentiated according to their lifestyles related to lamb consumption. These groups, due to their characteristics, could be called
“Gourmet”, “Disinterested”, “Conservative”, and “Basic”. The Gourmet group has characteristics
that make it especially interesting to market a product such as lamb confit. However, this group is
unaware of this product. Therefore, a possible strategy to expand the commercialization of light lamb
and the confit product would be guided marketing to this niche market.

 

Foods, 7(5), 80

Effect of the winter diet on meat quality traits of steers finished on mountain pasture with a barley supplement

The aim of this study was to evaluate the effect of two winter diets (WD) (100 F, i.e. 100% forage, 8.3 kg DM of lucerne hay + 0.3 kg DM of straw; and 65F:35C, i.e. 65% forage:35% concentrate, 5.4 kg DM lucerne hay + 0.3 kg DM straw + 3.0 kg DM barley), offered during 118 days on meat quality traits of 20-month old steers finished on mountain pasture supplemented with 4.1 kg DM barley d–1. Longissimus thoracis intramuscular fat content and its fatty acid profile were determined (in vivo) after one month on pasture. The intramuscular fat content, fatty acid profile, texture (1, 8 and 15 days of ageing), colour (1, 2, and 8 days of oxygen exposure) and sensorial quality (8 and 15 days ageing) were evaluated post-mortem after 163 days on the finishing diet. Intramuscular fat content and fatty acid profile were affected by the WD in vivo (p < 0.05) but not post-mortem. Meat pH was not affected by the WD but the texture was affected by the interaction between the WD and the ageing time (p < 0.001), maximum stress decreased more rapidly in the 100F diet in the first 8 days of ageing. Meat colour was only affected by the oxygen-exposure time (p < 0.001). Panel test variables were not affected by the WD, but ageing time affected beef flavour intensity (p < 0.05). In conclusion, the winter diet affected intramuscular fat content after one month of grazing but had no major effects on post-mortem meat quality of pasture-finished steers.

 

SJAR 10, 1037-1047

SNP included in candidate genes involved in muscle, lipid and energy metabolism behave like neutral markers

Studies of population structure and diversity in cattle have provided insights into the origins of breeds, their history and evolution, and allow the identification of global livestock diversity hotspots, which is important for conservation of diversity. Genetic diversity, genetic relationship, population structure, and the presence of hotspots of genetic diversity among 15 European bovine breeds from five countries were assessed using 435 single nucleotide polymorphisms (SNP) markers identified in candidate genes for muscle, lipid and energy metabolism, thus providing the opportunity to compare the breed relationships obtained using putatively functional markers with previous data using neutral loci. Individuals belonging to 11 breeds tended to be clearly assigned to a single cluster when the number of pre-defined populations reached a maximum in the likelihood of the data at K= 12, whereas Asturiana de los Valles, Danish Red,  Simmental, and Avileña-Negra Ibérica displayed a greater degree of admixture, which may be explained by their diverse ancestry. Although overall results were in agreement with those reported by studies based on neutral genetic variations, some additional breed relationship information emerged using markers in candidate functional loci, including the relationship between the Asturiana de los Valles and Piedmontese, and Danish Red and Charolais breeds. This study indicates that the analysed loci have not been main targets for selection or for adaptation processes, but also that SNP within candidate genes related with beef characteristics and performance may provide a slightly new perspective on past  breeding and may also help in the development of strategies for the rational conservation of livestock diversity.

 

Animal Production Science 55, 1164-1171

Estudio del color de diferentes tipos de carne bovina en España

Sur le marché espagnol, il existe huit dénominations de vente de la viande bovine. Le consommateur, au moment de l’achat, tient compte de la couleur et de l’apparence de la viande pour choisir ou non un  produit. Or, les différences de couleur mesurées objectivement ne correspondent pas toujours à cette segmentation commerciale. Au total, 78 échantillons de différents types de viande bovine commercialisés en Espagne ont été regroupés en quatre classes de couleur : blanche, rose, rouge et très rouge, par des mesures colorimétriques objectives. A partir des valeurs moyennes des paramètres de couleur et de leur dispersion (écart type), un standard a été calculé pour chaque type commercial.

Polymorphisms in twelve candidate genes are associated with growth, muscle lipid profile and meat quality traits in eleven European cattle breeds

2_1Current customers’ demands focus on the nutritional and sensory quality of cattle meat. Candidate gene approach allows identification of genetic polymorphisms that have a measurable effect on traits of interest. The aim of this work is to identify new molecular markers for beef production through an association study using 27 candidate genes and 314 purebred bulls from 11 European cattle breeds. Twelve genes were found associated with different lipid and meat quality traits, and among these stand out the considerable effect of CAST on fatness score, CGGBP1 on growth traits, HSPB1 on the percentage of lauric acid (12:0) and phospholipid docosahexaenoic acid (DHA 22:6 n -3), RORA on the ratio of light absorption (K) to light scattering (S) (K/S), and TNFA on lightness (L*). Most of these traits are related to post-mortem muscle biochemical changes, which are key factors controlling meat quality and consumers’ acceptance. Also, the variations produced on muscle fatty acid profiles, such as those of AANAT, CRH, CSN3, HSPB1, and TNFA, give insights into the genetic networks controlling these complex traits and the possibility of future improvement of meat nutritional quality.

Molecular Biology Reports 41, 4721-4731

Phenotypic and genotypic background underlying variations in fatty acid composition and sensory parameters in European bovine breeds

2_1Background: Consuming moderate amounts of lean red meat as part of a balanced diet valuably  contributes to intakes of essential nutrients. In this study, we merged phenotypic and genotypic information to characterize the variation in lipid profile and sensory parameters and to represent the diversity among 15 cattle populations. Correlations between fat content, organoleptic characteristics and lipid profiles were also investigated.

Methods: A sample of 436 largely unrelated purebred bulls belonging to 15 breeds and reared under comparable management conditions was analyzed. Phenotypic data -including fatness score, fat percentage, individual fatty acids (FA) profiles and sensory panel tests- and genotypic information from 11 polymorphisms was used.

Results: The correlation coefficients between muscle total lipid measurements and absolute vs. relative amounts of polyunsaturated FA (PUFA) were in opposite directions. Increasing carcass fat leads to an increasing amount of FAs in triglycerides, but at the same time the relative amount of PUFAs is decreasing, which is in concordance with the negative correlation obtained here between the percentage of PUFA and fat measurements, as well as the weaker correlation between total phospholipids and total lipid muscle content compared with neutral lipids. Concerning organoleptic characteristics, a negative correlation between flavour scores and the percentage of total PUFA, particularly to n-6 fraction, was found. The correlation between juiciness and texture is higher than with flavour scores. The distribution of SNPs plotted by principal components analysis (PCA) mainly reflects their known trait associations, although influenced by their specific breed allele frequencies.

Conclusions: The results presented here help to understand the phenotypic and genotypic background underlying variations in FA composition and sensory parameters between breeds. The wide range of traits and breeds studied, along with the genotypic information on polymorphisms previously associated with different lipid traits, provide a broad characterization of beef meat, which allows giving a better response to the variety of consumers’ preferences. Also, the development and implementation of low-density SNP panels with predictive value for economically important traits, such as those summarized here, may be used to improve production efficiency and meat quality in the beef industry.

Journal of animal Science and biotechnology, 5,20

Association of bovine meat quality traits with genes included in the PPARG and PPARGC1A networks

OLYMPUS DIGITAL CAMERAUnderstanding which are the genetic variants underlying the nutritional and sensory properties of beef, enables improvement in meat quality. The aim of this study is to identify new molecular markers for meat quality through an association study using candidate genes included in the PPARG and PPARGC1A networks given their master role in coordinating metabolic adaptation in fat tissue, muscle and liver. Amongst the novel associations found in this study, selection of the positivemarker variants of genes such as BCL3, LPL, PPARG, SCAP, andSCD will improvemeat organoleptic characteristics and health by balancing the n−6 ton−3 fatty acid ratio inmeat. Also previous results on GDF8 and DGAT1 were validated, and the novel ATF4, HNF4A and PPARGC1A associations, although slightly under the significance threshold, are consistent with their physiological roles. These data contribute insights into the complex gene-networks underlying economically important traits.

Meat Science 94, 328-335

Meat physicochemical properties, fatty acid profile, lipid oxidation and sensory characteristics from three North African lamb breeds, as influenced by concentrate or pasture finishing diets

índiceThis study investigated the meat quality of lambs from three North African breeds (Barbarine, BB; Queue Fine de l’Ouest, QFO; and Noire de Thibar, NT) reared on concentrate (S) or on pasture (P). A total of 18 P and 18 S lambs (20 kg initial body weight) were used, with 6 P and 6 S lambs for each breed. After 67 days, all lambs were slaughtered at 26 kg final body weight and meat quality was studied. The pH of S lambs 1 h post-mortem was lower than that of P lambs (p = 0.001). Water cooking loss, colour and sensory quality were not affected by both factors. The pasture and the concentrate meats had the same proportions of lipids and proteins; however QFO and BB breeds had more intramuscular fat than NT breed. The saturated fatty acid proportion was higher for S than P groups (50.63 vs. 44.48%, respectively) and for QFO compared to other breeds. C18:1 was higher for S groups, while C18:2, C18:3 and CLA were higher for P groups. The S group had higher lipid oxidation, while the QFO breed had the highest TBARS. P lambs may have healthier meat than S lambs and the NT breed had the leanest meat with higher concentration of desirable FAs.

Journal of Food Composition and Analysis 48 ,102–110

Effects of whole linseed and rumen-protected conjugated linoleic acid enriched diets on beef quality

frisonesInstrumental assessments and sensory tests were performed to evaluate the effects of diet and postmortem ageing time (1, 7 and 21 days) on beef quality. A total of 48 Friesian calves were randomly allocated to four dietary treatments: control, whole linseed (10% linseed), conjugated linoleic acid (CLA) (2% protected CLA), and whole linseed +CLA (10% linseed and 2% protected CLA). Animals were slaughtered at 458 ± 16.6 kg live weight and 11 months of age. Ageing was more significant than diet on most instrumental parameters. Meat from linseed enriched diets had greater drip loss ( P⩽ 0.001) and intramuscular fat ( P⩽ 0.01) than meat from animals fed CLA. Beef aged for 7 and 21 days had lower cooking losses ( P⩽ 0.01) and shear force ( P⩽ 0.001) than beef aged for 1 day. Lightness was affected only by display time. The addition of CLA in the diet increased hue and yellowness, whereas the inclusion of linseed decreased these values, as well as increased redness. Linseed in the diet decreased fat odour ( P⩽ 0.05), but increased beef ( P⩽ 0.01) and liver ( P⩽ 0.05) flavours. Meat aged for 21 days was significantly more rancid ( P⩽ 0.001), even under vacuum storage. Several organoleptic properties were improved with the inclusion of linseed in the diet, whereas they remained unaffected by the inclusion of CLA.

Puede consultar el documento completo aquí: Animal, 10, 709-717

A European vision for the Small Ruminant sector. Promotion of meat consumption campaigns.

FOTO CABRA DEL GUADARRAMASheep and goat production should adapt to current market demands if its future want to be secure. It is essential that are found ways to improve the competitiveness of the sector in all areas of the supply chain. Society’s point of view of the conditions surrounding livestock production is changing, and as a consequence, the Common Agricultural Policy (CAP) has been modified to include new environmentally-orientated requirements of farmers seeking subsidies. Sheep and goat production has the advantage over other types of livestock production in that it predominantly involves extensive production systems, but work is still needed to improve animal health and welfare, and food safety. People’s lifestyles are also changing, and the small ruminant sector should work to offer consumers new products presented in new ways, striking a balance between traditional forms of consumption (for example linked to festivities) and modern habits (including the purchasing of convenience products).

 

Puedes consultar el documento completo aquí

Calidad de la carne de 7 razas españolas vinculadas a sus sistema de producción

2cabeza asturianoEn España, de modo general, el consumidor de carne de vacuno le da poca importancia a la raza en comparación con otros países Europeos, a pesar de que la misma influye en otras características que sí considera relevantes como el aspecto (color, grasa intramuscular) o la terneza. Las razas bovinas rústicas y locales españolas están ligadas a una región geográfica particular y a un sistema de erra tradicional, donde varios factores como la edad y peso al sacrificio, el sexo, el grado de engrasamiento, el manejo, la alimentación y el tratamiento post-sacrificio intervienen conjuntamente en la definición de cada producto. Estos productos suelen promocionarse a través de denominaciones de origen o marcas de calidad que, por otro lado, permiten al consumidor reducir la incertidumbre cuando compran alimentos, ya que están asociadas a ciertas características sensoriales y/o procesos productivos distintivos.

Algunos autores han descrito la calidad de canal (Piedraflta et al., 2003) y las características bioquímicas (Gil et al., 2001) y sensoriales (Serra et al., 2008) de varias razas españolas vinculadas al sistema de producción, de modo que este trabajo se centra en la textura de la carne evaluada instrumentalmente y en algunas de sus características químicas.

Puede consultar el trabajo completo  aquí

Association study between variability in the SCD gene and the fatty acid profile in perirenal and intramuscular fat deposits from Spanish goat populations

Cabritos -72Despite the fact that goat meat is an important nutritive source throughout the world, aspects related to its characterization, and in particular genetic issues, have rarely been studied. Our objective was to assess the variability of the Stearoyl-CoA desaturase (SCD) gene in a sample of Spanish goat populations bred for both meat and dairy purposes and to look for possible associations between this genetic variability and the fatty acid composition in two fat deposits of industrial interest (perirenal and intramuscular). To do this, a goat population of 140 male suckling kids belonging to meat and dairy breeds was selected from farms in southern Spain. Four markers were detected in the SCD gene (SCD2, SCD3 172, SCD3 181, and SCD3 231) in the population, and significant associations were found between these markers and five individual fatty acids: C8:0, C11:0, C15:1, C16:1cis-9 and CLA 10 trans-12cis and two groups of fatty acids: SFA and MUFA. While significant associations in early (perirenal) fat depots for both dairy and meat purposes were observed, the only significant association in late (intramuscular) depots was found in goat kids bred for meat purposes. The SCD has been shown to be a useful gene to estimate the potential to show the different amounts of fatty acids in the fat of goat kids and use it in improvement programs which might provide an added value to goat meat and might help to produce a more competitive final product.

 

Puede consultar el documento completo aquí: Small Ruminant Research 136, 127-131

Percepción de los consumidores cobre la pechuga de pollo: segmentación de los consumidores en función de su estilo de vida

pechugaEl objetivo del trabajo fue estudiar la percepción que tienen los consumidores españoles sobre la pechuuga de pollo, atendiendo a su estilo de vida. La mayoría de los encuestados consume pollo una o dos veces por semana. La preferencia por el color estaba bastante equilibrada entre el blanco y el amarillento, aunque con ligera preferencia por el blanco.

La pechuga de pollo es percibida como un producto de conveniencia. El 70% de los encuestados compra pechuga de pollo porque es fácil de cocinar, mientras que sólo el 27% prefier el pollo entero.

Basándonos en el estilo de vida de los consumidores, se identificaron 4 grupos bien definidos:

“Urbanitas solteros”, “Tradicionales”, “Innovadores” y “Gourmet”. Estos tipos son consistentes con los encontrados en otros estudios.

Establecer los perfiles de consumidores en función de la percepción que tienen de un alimento concreto es útil para establecer estrategias de márketin.

Int.J Poultry Sci, 14, 262-275

 

http://albeitar.portalveterinaria.com

Valoración sensorial de la carne de cabrito por parte de los consumidores

cata-cabrito-coordinadoEsta cata es parte del proyecto titulado “Estudio de la influencia de la composición de la leche sobre la calidad de la canal y de la carne de cabritos de 8 razas españolas”.

 

Para realizar la cata, le dimos a 71 consumidores una bolsa con dos muestras de carne: una de un animal criado con leche natural y otra de un animal, de la misma raza, criado con leche artificial.

Les pedimos que la hiciesen a la plancha y que valorasen, en una escala de 1 (malo) a 10 (muy bueno) el sabor, la jugosidad y la impresión general.

En este documento puede ver los resultados de la prueba: cata de carne de cabrito

Efecto de la dieta invernal sobre la calidad de la carne de cebones finalizados en pastos de montaña suplementados con cebada

pardosEl objetivo del estudio fue evaluar el efecto de dos dietas invernales (WD) (100F, es decir, 100% forraje, 8,3 kg MS heno de alfalfa + 0,3 kg MS paja; y 65F:35C, es decir, 65% forraje:35% concentrado, 5,4 kg MS heno de alfalfa + 0,3 kg MS paja + 3,0 kg MS cebada), ofrecidos durante 118 días sobre algunas variables de calidad de la carne de cebones sacrificados a los 20 meses de edad, finalizados en pastos de montaña y suplementados con cebada (4,1 kg MS d–1). Se determinó el contenido en grasa intramuscular y el perfil de ácidos grasos del músculo Longissimus dorsi al mes de iniciarse el pastoreo (in vivo). Tras el sacrificio, se determinó el contenido en grasa intramuscular, el perfil de ácidos grasos, el pH, la textura instrumental (1, 8 y 15 días de maduración), el color (1, 2 y 8 días de exposición al oxígeno) y la calidad sensorial (8 y 15 días de maduración). La dieta invernal afectó al contenido en grasa intramuscular y a su composición después de un mes de pastoreo (p < 0,05) pero no al sacrificio. La dieta invernal no afectó al pH pero la textura se vio afectada por la interacción entre la dieta invernal y tiempo de maduración (p < 0,001). El color se vio afectado sólo por el tiempo de exposición al oxígeno (p < 0,001). La dieta invernal no afectó a las variables sensoriales (p > 0,05), pero la maduración afectó a la intensidad de flavor a vacuno (p < 0,05). En conclusión, la dieta invernal afectó a la cantidad de grasa intramuscular tras un mes de pastoreo pero no tuvo efectos importantes sobre la calidad post-mortem de la carne de los animales acabados en pastoreo.

SJAR 10, 1037-1047

Efecto del sexo y la explotación sobre la calidad de la canal y de la carne del cordero lechal de raza Ojinegra

ojinegraEl presente trabajo pretende caracterizar la calidad de la canal y de la carne de cordero lechal de la raza Ojinegra de Teruel. Para ello se utilizaron 64 corderos lechales, 32 de cada sexo, procedentes de 4 explotaciones comerciales. Los resultados mostraron que la edad al sacrificio, el rendimiento de la canal, las medidas objetivas de la canal y el color instrumental de la grasa y del músculo R. abdominis estuvieron afectados por la explotación de origen (P<0,05). Por el contrario, el sexo tuvo escaso efecto sobre los parámetros estudiados. En cuanto a la composición química de la carne, ni la explotación ni el sexo tuvieron efecto sobre ella (P>0,05). La composición de ácidos grasos intramuscular estuvo más afectada por la explotación que por el sexo, registrándose un efecto significativo de la explotación sobre el contenido de ácido oleico, ácido α-linolénico, ácido linoleico conjugado (9c-11t), el grupo de ácidos grasos poliinsaturados n-3 y la relación de ácidos grasos poliinsaturados n-6/n-3 (P<0,001). Sin embargo, el sexo solo afectó al contenido de ácido linoleico conjugado en la carne (P<0,05). De este trabajo se puede concluir que la calidad de la canal y de la carne de los corderos Lechal de raza Ojinegra está determinada por el factor explotación, mientras el sexo es un factor no determinante. Por ello, para obtener un producto comercial homogéneo, sería necesario definir las condiciones técnicas de producción.

ITEA 108, 522-536

Physicochemical and sensorial characteristics of four muscles from commercial crossbred pigs slaughtered at 130 kg body weight

Cerdo-BlancoEn España, una proporción considerable de cerdos son sacrificados a pesos elevados destinándose a la elaboración de jamón curado. La posibilidad de encontrar piezas cárnicas de calidad diferenciada, destinadas a consumo en fresco, optimizaría la producción de canales pesadas. El objetivo de este trabajo fue evaluar algunas características físico-químicas y sensoriales de cuatro músculos en 14 hembras Duroc × (Landrace × Large White) sacrificadas a 130 kg de peso vivo. De cada canal se extrajeron (dos por canal) los músculos: Longissimus thoracis (LT), Psoas major (PM), Lattissimus dorsi (LD) y Serratus ventralis (SV). Se evaluaron características físicas (color, pérdidas de agua y resistencia al corte), químicas (contenido en grasa intramuscular y su composición en ácidos grasos) y sensoriales (atributos relacionados con el aroma, el flavor, la textura y la aceptabilidad). El LT tuvo la mayor fibrosidad y los menores indicadores de capacidad de retención de agua, terneza y jugosidad. El PM mostró los menores contenidos en grasa intramuscular y ácidos grasos monoinsaturados y también en fibrosidad, y las mayores proporciones en humedad, C18:2n6 y ácidos grasos poliinsaturados. El LD tuvo el mayor tono amarillo, intensidad de olor y flavor a grasa. El SV proporcionó el mayor contenido en grasa intramuscular y color rojo y la menor resistencia al corte. Todos los músculos tuvieron similar puntuación en aceptabilidad global. En conclusión, se detectaron numerosas e interesantes diferencias entre los músculos estudiados, lo que sugiere que podrían ser comercializadas individualmente como piezas cárnicas de calidad diferenciada, optimizando así la producción de canales de cerdos pesados.

SJAR 10, 701-711

Effects of the FecXR allele of BMP15 gene on the birth weight, growth rate and carcass quality of Rasa Aragonesa light lambs

corderoA new allele of the BMP15 gene (FecXR) that increases prolificacy has been recently described in the Rasa Aragonesa sheep breed. The present study was conducted to evaluate the effects of lamb and maternal genotypes on birth weight, growth and meat quality traits. Two experiments were carried out. In experiment 1, the progeny of heterozygous (R+) and wild-type (++) dams mated to wild-type hemizygous (+) rams from four flocks were tested to estimate the effects of the FecXR allele on birth weight and average daily gains (ADGs) until weaning and slaughter (at approximately 50 and 100 days of age, respectively). Three maternal/lamb genotype groups were studied: wild-type progeny from ++ ewes (females: ++/++, n = 62; males: ++/+, n = 60), wild-type progeny from R+ ewes (females: R+/++, n = 31; males: n = 28 R+/+) and progeny carrying the FecXR mutation born to R+ ewes (females: R+/R+, n = 35; males: R+/R, n = 28). No significant differences were observed in the birth weights or ADGs between the FecXR genotype groups in either female or male lambs. In experiment 2, 37 male lambs (13 ++/+, 12 R+/+ and 12 R+/R) were used to evaluate the effect of the FecXR genotype groups on carcass characteristics and meat quality traits. All lambs were classified within the normal ranges for the “Ternasco de Aragón” commercial category, and no significant differences were observed between the genotype groups. We conclude that birth weight, growth traits, light lamb carcass characteristics and meat quality traits were not affected by the maternal and lamb FecXR genotype combinations that were studied.

Small Ruminant 108, 45-53

Effect of two Spanish breeds and diet on beef quality including consumer preferences

bescos_2006%20064Farmers in dry mountain areas are changing their management strategies to improve livestock farming efficiency, by using different forages or different breeds. The effect of breed (Parda de Montañana vs. Pirenaica) and finishing diet
(grazing on meadows vs. a total mixed ration (50% alfalfa, 40% maize grain, 10% straw)) on carcass characteristics and meat quality of steers was studied.

Parda de Montaña had a greater (P < 0.01) amount of intramuscular fat than Pirenaica. The finishing diet did not
influence carcass fat color, but fatty acid composition was slightly affected. Finishing steers on a total mixed ration increased the percentage of fat of the 10th rib (P < 0.001). Supplementation with concentrates increased the diet energy concentration and also increased the dressing percentage. Both breeds had similar carcass characteristics. Consumers preferred beef from the Pirenaica breed because of its greater tenderness. Consumers did not differentiate between beef from animals fed different finishing diets. However, consumers who like meat very much preferredmeat aged in a cooler at 4 ◦C for 15 days rather than 8 days.

 

doi 10.10002/jsfa.634

Effect of nanocomposite packaging containing different proportions of ZnO and Ag on chicken breast meat quality

pechugaThis study reports the antimicrobial capacity, nanoparticle migration properties and the influence on some meat quality traits of a packaging based on a low density polyethylene (LDPE) blended with a nano-antimicrobial master batch composed of Ag and ZnO (5% and 10% w/w). Meat was aged for storage times of 0, 7, 10, 15 or 21 days. Composition of the package atmosphere, some microbiological analyses, meat sensorial quality, meat color, visual appearance score and lipid oxidation index (TBAR) values were determined. Irrespective of the packaging, the O2 concentration decreased and the CO2 concentration and count for all types of microbe increased with storage time. Redness, yellowness and Chroma of the breast meat increased until to 7 days whereas maximum lightness values were found at 15 days. Visual appearance scores decreased and lipid oxidation increased with storage time. It was found that adding ZnO + Ag nanoparticles to LDPE packaging has an antimicrobial effect whilst migration amounts were well within those allowed by law.

 

Journal ofFood Engineering 123, 104-112