Publicaciones de la categoría: Vacuno

Eating quality of young bulls from three Spanish beef breed-production systems and its relationships with chemical and instrumental meat quality

Sensory characteristics of longissimus thoracis muscle from three local Spanish beef breed-production systems and their relationships with chemical and instrumental meat quality traits were studied. Young bulls of Bruna dels Pirineus (BP; n = 69), Avilen˜a-Negra Ibe´rica (A-NI; n = 70) and Morucha (MO; n = 70) breeds were reared in their own production systems. MO breed showed the highest water holding capacity and also the highest thawing loss and haem pigment content (P < 0.001). No differences in moisture and protein contents were found among breeds. A-NI showed the highest intramuscular fat (IMF, P < 0.05) and total collagen (P < 0.001) contents, whereas BP showed the lowest IMF content (P < 0.05) and the highest collagen solubility (P < 0.001). Beef flavour, tenderness and juiciness accounted for the eating quality differences among the three breed-production systems. Meat from A-NI was rated significantly higher (P < 0.01) for beef flavour and tenderness than that from BP and MO animals. Furthermore, MO showed the lowest juiciness (P < 0.001) which could be due to its higher thawing loss. Within the three breeds, thawing loss was negatively correlated with juiciness
and, likewise cooking loss with juiciness and tenderness (P < 0.05). The canonical discriminant analysis showed that the three breeds were significantly different (P < 0.05) from each other according to sensory attributes, which justifies their involvement in different protected geographical indications (PGI).

 

Meat Science 79, 98-104

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Identifying market segments in beef: Breed, slaughter weight and ageing time implications

In this paper we propose a method to learn the reasons why groups of consumers prefer some beef products to others. We emphasise the role of groups since, from a practical point of view, they may represent market segments that demand different products. Our method starts representing people’s preferences in a metric space; there we are able to define a kernel based similarity function that allows a clustering algorithm to identify significant groups of consumers with homogeneous likes. Finally, in each cluster, we developed, with a support vector machine (SVM), a function that explains the preferences of those consumers grouped in the cluster. The method was applied to a real case of consumers of beef that tasted beef from seven Spanish breeds, slaughtered at two different weights and aged for three different ageing periods. Two different clusters of consumers were identified for acceptability and tenderness, but not for flavour. Those clusters ranked two very different breeds (Asturiana and Retinta) in opposite order. In acceptability, ageing period was appreciated in a
different way. However, in tenderness most consumers preferred long ageing periods and heavier to lighter animals.

 

Meat Science 74, 667-675

Using machine learning procedures to ascertain the influence of beef carcass profiles on carcass conformation scores

In this study, a total of 163 young-bull carcasses belonging to seven Spanish native beef cattle breeds showing substantial carcass variation were photographed in order to obtain digital assessments of carcass dimensions and profiles. This dataset was then analysed using machine learning (ML) methodologies to ascertain the influence of carcass profiles on the grade obtained using the SEUROP system. To achieve this goal, carcasses were obtained using the same standard feeding regime and classified homogeneous conditions in order to avoid non-linear behaviour in grading performance. Carcass weight affects grading to a large extent and the classification error obtained when this attribute was included in the training sets was consistently lower than when it was not. However, carcass profile information was considered non-relevant by the ML algorithm in earlier stages of the analysis. Furthermore, when carcass weight was taken into account, the ML algorithm used only easy-to-measure attributes to clone the classifiers decisions. Here we confirm the possibility of designing a more objective and easy-to-interpret system to classify the most common types of carcass in the territory of the EU using only
a few single attributes that are easily obtained in an industrial environment.

 

Meat Science 73, 109-115

Carcass characterisation of seven Spanish beef breeds slaughtered at two commercial weights

A total of 159 bulls representing seven Spanish beef breeds were fed with concentrates, managed in the same conditions and slaughtered at two commercial weights (veal and young-bull). Carcasses were measured and classified in order to characterise the carcass variation in the Spanish beef market and to assess the relationship among carcass measurements and grading. Principal Component Analysis clearly separated commercial types regardless the inclusion of the carcass weight in the input data. Within commercial weights the studied breeds clustered into three groups according to muscular development and carcass classification score: high meat producer breeds (Asturiana de los Valles and Rubia Gallega); medium meat producers (Parda Alpina and Pirenaica); and low meat producers (Avilen˜a, Retinta and Morucha). The perimeter and width of the leg (muscular development) besides the length and width of the carcass basically defined these three carcass types. Conformation was an important trait in explaining variation between breeds because its values were positively correlated with muscular development and carcass compactness.

 

Meat Science 71, 514–521

Effect of muscular hypertrophy on physico-chemical, biochemical and texture traits of meat from yearling bulls

The effect of the presence of the double-muscling gene either homozygous (mh/mh) or heterozygous (mh/+) on the physicochemical, biochemical and texture traits of Longissimus thoracis muscle of yearling bulls of the Asturiana de los Valles (AV) breed was studied. Meat of mh/mh bulls had lower amount of intramuscular fat (p < 0:001) and also lower total (p < 0:01) and insoluble collagen (p < 0:05), although the double-muscling genotype did not affect collagen solubility. Homozygous animals had lower pigment content (p < 0:05) and a lighter meat, showing lower water holding capacity, estimated as expressible juice under pressure (p < 0:001). Genotype affected significantly the metabolic traits of muscle, with mh/mh animals having higher muscle glycolytic metabolism, assessed by a higher (p < 0:001) lactate dehydrogenase (LDH) activity and lower (p < 0:001) oxidative activity of the isocitrate dehydrogenase (ICDH). The percentage of myosin heavy chain I in muscle was lower, although not significantly, for mh/ mh bulls compared to mh/+ bulls. Texture measurements performed on raw material showed that meat of mh/mh bulls had lower resistance to total and 80% compression, which means lower background or collagen toughness. However, there were no differences between genotypes on shear force of cooked meat. Therefore, the physico-chemical, biochemical and texture trait of meat from mh/
mh and mh/+ bull are in general significantly different, which could affect the sensorial quality of meat and hence the consumer acceptance.

 

Meat Science 68, 567-575

The effects of slaughter weight, breed type and ageing time on beef meat quality using two different texture devices

Physical characteristics of meat texture were measured on the M. longissimus dorsi of 103 entire yearling bulls in terms of the effect of slaughter weight (300 or 550 kg), breed type (double muscle, fast growth, dual purpose and unimproved) and ageing time (1, 7 and 21 days). Live weight, breed and ageing effects were statistically significant for all the Warner–Bratzler variables measured on cooked meat. For compression values (raw meat), live weight had a significant effect at higher compression rates, which were higher in the heaviest animals, and ageing had a significant effect at lower compression rates, which were progressively lower as ageing time increased. Breed effect was significantly different for all compression values. At the highest rates of compression, unimproved and dual purpose breed types had the highest values. At 20% compression, double muscled animals had the lowest values, but only at one day of ageing. The differences between breed types tended to decrease or disappear with longer periods of ageing.

 

Meat Science 66, 925-932

Characterisation of young bulls of the Bruna dels Pirineus cattle breed (selected from old Brown Swiss) in relation to carcass, meat quality and biochemical traits             

Seventy-four young bulls of the Bruna dels Pirineus beef cattle breed were reared in a typical production system and slaughtered at an average age of 381 days and live weight of 541 kg. The animals were evaluated for productive traits, carcass quality, meat quality, eating quality and biochemical characteristics of m. longissimus thoracis (LT). Biochemical measurements included intramuscular fat (IMF) and collagen proportion, haem pigment concentration, lactate dehydrogenase and isocitrate dehydrogenase activities and type I (MHC I) fibre percentage determined by ELISA. Bruna dels Pirineus bulls achieved high growth rates during the fattening period (1.63 kg/day) and showed good carcass quality, with a high dressing-out proportion (607 g/kg, hot carcass), a good conformation score (U; EUROP) and a moderate fatness score (3;1–5). Carcass composition was estimated from the sixth rib joint dissection (682 g/kg lean proportion, 127 g/kg total dissectable fat and 163 g/kg bone). IMF (24.3 g/kg) and MHC I (27.9%) showed high variabilities (CV>30%). Sensory analysis of LT included beef and livery odour and flavour intensity, and overall tenderness and juiciness assessment of loin samples (14-day ageing). Beef odour and flavour were slightly positively correlated with IMF and carcass fatness score (P<0.05). Fatness, MHC I, insoluble collagen and cooking losses tended to affect the livery flavour intensity positively. This variable was significantly higher in meat from bulls of lower carcass quality (i.e. lower conformation score, lower lean proportion; P<0.05) and higher type I fibre percentage. Loin overall tenderness and juiciness were not affected by the biochemical traits studied, however, they were negatively affected by cooking loss (P<0.05).

Meat Science 66, 425-436

  

      

Efecto de la raza y temperatura interna de cocinado sobre algunas características de la textura de la carne bovina

Se utilizaron 30 animales de dos genotipos diferentes Holstein (lechera) y Pirenaica (cárnica) para estudiar el efecto de la raza y la temperatura de cocinado sobre algunas características de textura de la carne bovina. Para ello se utilizaron filetes del músculo L. thoracis, distribuidos al azar en tres tratamientos: crudo, cocinados al baño maría hasta alcanzar una  temperatura interna de 55ºC o cocinados de la misma forma hasta los 70ºC. Todas las muestras fueron ensayadas mediante dos métodos: Warner-Bratzler (WB) y compresión. En la prueba de WB se registraron las variables de fuerza máxima, máximo esfuerzo y dureza. En la de compresión, fuerza máxima en compresión y esfuerzo al 20% y 80%. Los resultados se
analizaron por medio de un GLM y del cálculo de correlaciones bivariadas de Pearson. La raza afectó significativamente
a las características de textura, pero la influencia de la temperatura de cocinado fue mayor. No se encontraron  interacciones entre los efectos principales. La carne de los animales de genotipo lechero fue más dura que la carne de los animales de aptitud cárnica. El incremento de la dureza con la temperatura no fue lineal, siendo mayor en el rango crudo-55ºC que en la fase 55-C-70ºC.

 

ITEA, 106 77-88

Effects of the forage content of the winter diet on performance and carcass quality of steers finished on mountain pasture with a barley supplement

bescos_2006%20064Eighteen Parda de Montaña steers (366 kg liveweight, 10 months of age) received diets of either forage (F; lucerne hay + straw) or forage and concentrate (FC; lucerne hay + straw + barley) during the winter feeding period, which lasted 118 days. Thereafter, steers continuously grazed in meadows in a dry mountain area until the end of the grazing period in September (160–167 days) and received 4.1 kgDMbarley per head for the final 103–110 days of the grazing season. The steers that received the FC winter diet were heavier (491 vs 457 kg, respectively; P < 0.05) and had deposited more fat (7.2 vs 5.8 mm, P < 0.05) and muscle (63 vs 54 mm, P < 0.05) at the end of the winter than the steers that received the F winter diet. During the grazing period, the steers from both groups had similar weight gains (0.728 and 0.756 kg/day for FC and F diet, respectively). At slaughter, the steers from both groups were of similar age (590 vs 599 days, for FC and F diet, respectively) and had similar liveweights (560 vs 539 kg), muscle depths (54 vs 63 mm) and subcutaneous fat thicknesses (7.3 vs 7.2 mm). The serum leptin concentration differed only at the end of the winter period, when steers on the FC diet had higher leptin concentrations than did steers on the F diet (P < 0.05), reflecting differences in fatness. The carotenoid concentration in the plasma during the winter feeding period was higher in steers on the F than on the FC winter diet, but this difference was not seen during the grazing period. Carcasses from steers on the FC winter diet were heavier (324 vs 300 kg; P < 0.05) and had a higher dressing percentage (57.3% vs 56.1%, P < 0.05) than those reared on the F winter diet, but the fatness and conformation scores were similar between the groups. The percentages of fat, muscle and bone in the commercial dissection and 10th rib dissection did not differ between the winter diet groups. In conclusion, the differences resulting from the winter feeding period disappeared after the grazing period, and the carcass quality did not differ between the diets. Therefore, both strategies are equally technically advisable.

Animal Production Science 52, 823-831

Assessment of breed type and ageing time e€ects on beef meat quality using two di€erent texture devices

Forty-two male yearlings were used to assess the in¯uence of breed type and ageing time on beef texture. Samples of the M.
longissimus dorsi of four breed types [double muscled (DM), dual purpose (Brown Swiss, BS), fast growth (FG) and  unimproved type (UT)] were aged for 1, 3, 7, 10, 14 or 21 days at 4C and frozen at ÿ18C until analysed. Cooked samples (to end-point of 70C) were assessed using a Warner±Bratzler (WB) device. Raw samples were assessed using a compression device in which transverse elongation was prevented. There were no signi®cant di€erences in WB values of cooked meat due to breed type, but ageing had a signi®cant (P<0.05) on maximum load. Ageing, but not breed type, had a signi®cant e€ect on the compression values of raw meat at low compression rates (P<0.001). Compression values, of raw samples, at 80% compression di€ered signi®cantly (P<0.001) between breed types, but were not a€ected by ageing. Compression values of raw samples, at 80% compression, were a€ected by breed type, probably because of genotype di€erences in the contribution of connective tissue.

Meat Science 55, 371-378

Breed type and ageing time e€fects on sensory characteristics of beef strip loin steaks

Forty-two yearling males from seven European beef breeds were used to study breed type and ageing time e€ects on meat sensory quality. Breeds were grouped according to their double muscled condition (DM), dual-purpose condition (Brown Swiss, BS), fast growth rate (FG) and rustic characteristics (RT). Vacuum packaged loin chops were aged for 1, 3, 7, 10, 14 and 21 days at 4C and evaluated by a trained taste panel. Ageing time had the main in¯uence in all the studied sensorial descriptors. Breed type did not a€ect juiciness, ®brosity or overall ¯avour intensity. Interactions between breed type and ageing appeared in global odour intensity, tenderness (p < 0:05) and acid ¯avour intensity (p < 0:01). All breed types showed higher tenderness scores as ageing period increased but, comparatively, those with higher scores at an early postmortem period (DM, FG) showed lower scores at a late postmortem time. A possible faster, but shorter and less intensive meat tenderisation rate in animals with double muscled condition, and its particular collagen characteristics, in relation to BS and RT groups, could explain our findings.

Meat Science 51, 383-390

Effect of ageing method, ageing period, cooking method and sample thickness on beef textural characteristics

The effect of the ageing method (bone-in or boneless), ageing period (7 or 14 days), cooking method (grilling or water bath preparation) and sample thickness (1, 2 or 4 cm) on the meat texture characteristics of the longissimus thoracis muscle of six young, commercial bulls was measured using a texture analyser incorporating compression and Warner-Bratzler devices. The sarcomere length of the raw meat and cooking losses were also recorded. The ageing method and ageing period had more influence on the textural properties studied than either the cooking method or sample thickness. Cooking losses were, however, mainly influenced by the cooking method. Although the cooking method had no significant effect on meat toughness, the meat tended to be tougher when grilled than when prepared in a water bath. Meat tenderness mainly improved during the first week of storage.

SJAR 6, 25-32

Intrabreed variability and relationships for 41 carcass and meat traits in Pirenaica cattle

A total of 125 13-month-old, entire males of the Pirenaica breed were selected from among the progeny of nine different
sires. They were used to study the intrabreed variability of 41 carcass and meat traits, including weights, lengths,
diameters and perimeters, grading parameters, dissection of the sixth rib, pH, colour and meat texture variables, and
sensory attributes. Pearson correlations were also calculated. Coefficients of variation ranged from 3.5% for dressing
percentage to 47.0% for fat red index, and all of the values could be considered within the normal range for cattle. Carcass
traits showed lower variability (11.7% on average) than meat variables (14.8% on average). Hence, to achieve a
standardised product, it would be desirable to include in the breeding selection programme a variable that could be
measured on the carcass and that can predict meat quality. Nevertheless, from the results of the present study, none of
the variables studied fulfil this requirement, and further studies would be necessary to widen our knowledge on this
subject.

SJAR 6, 546-558

The use of correspondence analysis in the study of beef quality: a case study on Parda de Montaña breed

The present study shows the usefulness of a multivariate technique —correspondence analysis—- for simultaneously
representing continuous and categorical variables in graphical form. A comparison was made of the results of sensory
tests of beef quality performed by a trained panel and by consumers. The latter included the collection of data to
produce consumers profiles and the recording of a number of consumers habits. Spearman correlation coefficients
were calculated independently for the variables measured in both the panel and consumer tests. Two correspondence
analyses were then performed: the first one involving the consumer profiles and the values of the variables measured
in the consumer test, the second one to determine the relationships between the panel and consumer test scores. In the
plot corresponding to the first analysis, the two axes accounted for 52.2% of the inertia and showed that age did not
have an important effect on any measured variable. Consumers previous experience has been shown to be an important
factor defining consumer liking of the product. In the plot for the second analysis the two axes accounted for 82.3%
of the inertia and showed that there was no correspondence between overall consumer liking of the product and any
of the panel variables. These results therefore suggest that the panel test is not a good predictor of consumer behaviour.

SJAR 7, 876-885

Apreciación visual de la carne bovina y su relación con el espacio de color CIELab

El color es el factor de calidad más importante a la hora de la compra puesto que el consumidor lo utiliza como indicador de frescura. Numerosos estudios sobre la vida útil de la carne utilizan las coordenadas triestimulus del espacio de color CIELab, pero si bien estas variables son muy útiles para tipificar el color de la carne y sobre todo, son objetivas; el uso de las mismas plantea dudas de cómo ven o valoran esa carne los humanos. Además, es complicado definir el momento en que será rechazada por los consumidores. Se usaron 24 terneros de la categoría comercial Añojo. El longissimus thoracis de cada animal se extrajo, se muestreó y fue envasado con atmósfera modificada. Durante 8 días la carne se evaluó subjetivamente (1- Carne rojo oscuro o marrón a 5- Rojo extremadamente brillante) y se midió el color instrumental de la misma. Varias técnicas uni- y multi-variantes, lineales y no lineales y un algoritmo de aprendizaje automático se usaron para estudiar las relaciones entre la evaluación visual subjetiva y las variables de color instrumental. El uso de aprendizaje automatico y reglas no lineales nos ofrece una aproximación a la nota de los evaluadores más precisa que otros métodos y demuestra que no se puede interpretar el color de la carne durante el tiempo de exposición de una forma lineal o usando las variables de forma independiente, siendo más precisas la luminosidad y la saturación, en detrimento de los índices de rojo y amarillo.

ITEA, 108, 222-232

Efecto del sexo y del cruzamiento sobre la calidad instrumental y sensorial y sobre la aceptación de la carne de añojos de la raza Avileña-Negra Ibérica

Se estudió el efecto del cruce industrial (Avileña-Negra Ibérica en pureza o cruzados por Charolés) y del sexo sobre el pH, color la carne y valoración sensorial con panel entrenado y consumidores de la carne de 30 animales de categoría añojo. El color estuvo más influenciado por la base genética que por el sexo, resultando menos luminosa la carne de los animales en pureza que la de los cruzados. En general, la carne de las hembras fue mejor valorada que la de los machos. La maduración incrementó la jugosidad y terneza de la carne, así como la intensidad de su olor y flavor. El sexo del consumidor no
influyó sobre la valoración de la carne, pero la edad sí.

ITEA 107, 239-250

Live weight, body size and carcass characteristics of young bulls of fifteen European breeds

A total of 436 young bulls from fifteen Western European breeds, including beef, dairy and local types from five countries, were studied to assess variability in live weight, live weight gain, body measurements and carcass traits. Animals were logged indoors, and fed a diet based on concentrate and straw offered ad libitum from 9 months of age to slaughter at 15 months of age. The weight, body length, height at withers and pelvis width, of the animals were recorded at 9, 12 and 15 months of age. After slaughter, 15 carcass variables were recorded, including carcass weight, EU classification scores, morphological measurements and dissection data. Data were analysed by GLM, regression and principal component analysis procedures.
Significant differences were found between breeds for all variables studied, however, the body size measurements and the
carcass traits were more useful to discriminate among cattle breeds, than either live weight or daily gain. With respect to the body size and carcass traits the studied breeds could be grouped as:
– Specialized beef breeds, comprising Piemontese, Asturiana de los Valles, Pirenaica, Limousin, South Devon, Charolais and
Aberdeen Angus, all of which were characterized by high muscularity, wide pelvis and medium height and a low to medium level of fatness.
– Local and dairy breeds, comprising Jersey, Casina, Highland, Holstein and Danish Red, the latter two breeds were tall animals, while the former three breeds were small in size. In general the group was poorly muscled and tended to have a high or medium level of fat.
– Intermediate group, Avileña, Marchigiana and Simmental: these breeds were characterized by an intermediate muscle
conformation and fatness level and were relatively tall.

Livestock Science 114, 19–30

Carcass quality of 10 beef cattle breeds of the Southwest of Europe in their typical production systems

A sample of about 70 young bulls of each of 10 beef cattle breeds from France and Spain, reared in their typical production systems, was studied regarding growth and carcass quality traits. There were large differences between and within breed-systems. The animals slaughtered in Spain weighed between 444 and 551 kg, whereas the range in France was from 610 to 750 kg. Growth showed a linear tendency; the daily weight gain ranging from 1.03 to 1.65 kg/ day. Asturiana de los Valles and Pirenaica were, among the Spanish populations, the breed-systems with more muscle (around 75%) and less fat  (8–10%) in the carcass, whereas Avilen˜a-Negra Ibe´rica, Morucha and Retinta showed opposite characteristics (60–65%
muscle and 17–19% total fat at the 6th rib). Bruna dels Pirineus and Asturiana de la Montan˜a occupied an intermediate position. All of the French breed-systems, Aubrac, Gasconne and Salers surpassed 73% muscle, while the percentage of total fat ranged from 7.6 to 10%. Salers breed-system also showed the longest and thinnest hind-limb. In the wide range of carcass weights studied in this paper, the general relationships among carcass traits were confirmed. Animals with the better conformation were also leaner. Longer carcasses tended to be associated with poor conformation and fatness. Bone content was clearly opposed to carcass conformation and muscle content.

Livestock Science 82, 1-13

Caracterización de la canal y la carne de la raza bovina Menorquina

Se evaluaron las características de la canal y de la carne de los animales de la raza bovina Menorquina como paso previo para la creación de una marca de calidad. Se utilizaron 8 machos de un año de edad. Las variables estudiadas fueron:
conformación, engrasamiento, morfometría de la canal, pH, color, textura y valoración sensorial. La canal resultó mejor que la de la Frisona, su competidora directa en la isla. La raza Menorquina presentó valores bajos en el análisis instrumental de la textura, siendo bien valorada sensorialmente.

Archivos de zootecnia, 59, 467-470

Calidad instrumental de la carne de bovino de siete razas españolas


La calidad es una de las características comunes a cualquiera de las denominaciones específicas de carne de vacuno que existen en España. Con el fin de objetivar esta calidad se han estudiado, en tres años, 120 añojos cebados y sacrificados en idénticas condiciones. Estos animales pertenecían a las razas: Asturiana de los Valles, Avileña-Negra Ibérica, Parda Alpina, Pirenaica, Retinta y Rubia Gallega (18 animales/ raza) y Morucha (12 animales). En cada animal se analizó: pH, capacidad de retención de agua (CRA), pérdidas por cocinado y conservación, contenido de mioglobina, colágeno total y soluble, dureza instrumental con la célula de Wamer- Bratzler y color de la carne y de la grasa subcutánea (L* a* b*). Las razas Rubia Gallega y Retinta presentaron una menor cantidad de colágeno total (p contenido en pigmentos hemínicos. Las mayores pérdidas de cocinado e inferior CRA correspondieron a las razas Pirenaica y Parda Alpina, no existiendo en pH diferencias importantes entre razas.

Archivos zootecnia 48, 397-402

Carne de vacuno enriquecida con lino y vitamina E

OLYMPUS DIGITAL CAMERASe estudió el efecto de la inclusión en el pienso de cebo de un 10% de semilla de lino  o lino+vitamina E sobre la calidad de la carne de 46 terneros de raza Pirenaica sacrificados a dos niveles de engrasamiento.

La dieta no afectó ni a la composición química de la carne ni al color. Tampo se modificó sustancialmente el perfil de ácidos grasoas, de modo que no existen diferencias estadísticas entre dietas para la cantidad de SFA, MUFA o PUFA. Sin embargo, la inlcusión de lino provocó que la ratio n6/n3, fuera menor que en el lote control, por lo que podemos decir que la carne de los animales que habían tomado lino sería algo más saludable que la de los animales del lote control.

 

Meat science 96, 1258-1265