Bienestar animal de corderos ternascos durante su espera en matadero

El presente trabajo consistió en valorar la respuesta de estrés al que son sometidos los corderos desde que llegan al matadero hasta su sacrificio en distintas épocas del año, primavera y verano. Se tomaron muestras de sangre durante el sacrificio del animal para la valoración de diferentes parámetros sanguíneos de respuesta de estrés y tras el faenado se valoró la calidad de la canal y de la carne de los corderos. Se encontraron diferencias significativas con mayores valores para los corderos sacrificados en verano en el número de linfocitos, lactato deshidrogenasa (LDH), cortisol y pHs y menores en el número de leucocitos, neutrófilos, relación neutrófilos/linfocitos, volumen corpuscular medio, concentración de glucosa y rendimiento de la canal. Los corderos sacrificados en verano tuvieron más comprometido su nivel de bienestar por el mayor nivel de cortisol y LDH junto con unos pHs más elevados, lo que hace que la calidad de la carne sea inferior a los sacrificados en primavera

Efecto de la suplementación con antioxidantes en la dieta de corderos sobre la calidad de su carne enriquecida en ácidos grasos omega-3

Se ha evaluado el efecto antioxidante de la suplementación en la dieta de corderos con vitamina E o con extracto de uva rico en polifenoles en carne enriquecida en ácidos grasos omega-3 mediante la alimentación y conservada durante 0, 6 y 12 días en atmósfera modificada. Se observó una interacción significativa (p<0.001) entre el tipo de suplementación y el tiempo de conservación para los valores de oxidación lipídica y de proporción de metamioglobina, mostrando la carne suplementada con vitamina E los valores más bajos al final de la conservación. Los niveles de ácidos grasos poliinsaturados descendieron durante la conservación en el grupo control y en el grupo suplementado con extracto de uva, permaneciendo más estables en el grupo suplementado con vitamina E. Se observó una interacción significativa (p<0.001) entre la suplementación y el tiempo de conservación para el porcentaje de ácidos grasos omega- 3, manteniéndose los valores estables durante la conservación en la carne suplementada con vitamina E. La suplementación en la dieta con vitamina E mostró un efecto antioxidante en la carne durante su conservación mayor que el resto de dietas estudiadas

Efecto de la adicción de extracto de vino tinto en la conservación de hamburguesas de cordero enriquecidas en ácidos grasos omega-3

Red wine is a great source of polyphenols compounds, which exert a high antioxidant capacity. The effect of red wine extract (EV) on the oxidative stability of lamb patties in terms of metmyoglobin (MetMb) formation, lipid oxidation, protein oxidation, and the stability of docosahexaenoic fatty acid (DHA) was investigated. Ground lamb meat enriched in ω3 fatty acids was divided into four treatments. Three treatments were supplemented with 3 doses of EV being 50 (EV1), 100 (EV2) and 200 (EV3) mg GAE/kg meat and, the last one, without antioxidant supplementation, was kept as control (C). The lamb patties were stored under MAP (70% O2/30% CO2) during 9 days. There was an interaction between treatment (L) and storage period (PC) for MetMb proportion (p<0.001) and DHA content (p<0.01). Groups EV2 and EV3 showed less MetMb proportion and higher DHA content at the end of storage period in comparison to groups EV1 and C. Lipid and protein oxidation was affected by storage period (p<0.001), increasing in all treatments.El vino tinto es una gran fuente de compuestos polifenólicos que presentan una gran capacidad antioxidante. El objetivo de este estudio fue evaluar el efecto de la adición de extracto de vino (EV) en la estabilidad oxidativa de hamburguesas de cordero, estudiando la formación de metamioglobina (MetMb), la oxidación lipídica, la oxidación proteica y el contenido en ácido docosahexaenoico (DHA). Se realizaron 4 lotes de carne picada de cordero, todos enriquecidos en ácidos grasos ω3. A tres lotes se les adicionó EV para obtener una concentración final de 50 (EV1), 100 (EV2) y 200 (EV3) mg GAE/kg de carne y el último lote, sin antioxidantes, se mantuvo como control (C). Las hamburguesas se conservaron en MAP (70% O2/30% CO2) durante 9 días. Se observó una interacción entre el lote (L) y el periodo de conservación (PC) para la proporción de MetMb (p<0,001) y el contenido en DHA (p<0,01). Los lotes EV2 y EV3 presentaron menor proporción de MetMb y mayor contenido en DHA que los lotes EV1 y C. La oxidación lipídica y proteica estuvo afectada por el periodo de conservación (p<0,001) aumentando en todos los tratamientos

Volatile compounds in Spanish dry-fermented sausage 'salchichón' subjected to high pressure processing. Effect of the packaging material

The effect of high pressure treatment (400 MPa, 10 min at 12 °C) on the volatile profile of Spanish dry-fermented sausage 'salchichón', packaged with or without aluminium foil in a multilayer polymeric bag, was investigated. The analysis of the volatile fraction was carried out by dynamic headspace extraction coupled to gas chromatography-mass spectrometry. Pressure-treated samples showed significantly higher levels of alcohols, aldehydes and alkanes and lower levels of two methylketones as compared with control samples. An intense migration was observed of compounds from the plastic material into the product, mainly linear and branched-chain alkanes, alkenes and benzene compounds. Most of these migrating compounds were significantly more abundant in pressurized samples than in untreated samples. © 2009 Elsevier Ltd. All rights reserved

Volatile compounds in fresh meats subjected to high pressure processing Effect of the packaging material

The effect of high pressure treatment (400 MPa, 10 min at 12 °C) on the volatile profile of minced beef and chicken breast, packaged with or without aluminum foil in a multilayer polymeric bag, was investigated. The analysis of the volatile fraction was carried out by dynamic headspace extraction coupled to gas chromatography-mass spectrometry. Pressurization produced significant changes in the levels of some volatile compounds presumably coming from microbial activity. Some alcohols and aldehydes decreased, while other compounds, such as 2,3-butanedione and 2-butanone, were more abundant in high pressure processed meats. A significant migration of compounds from the plastic material was observed, mainly branched-chain alkanes and benzene compounds. Two functions built by the principal component analysis explained a high percentage of the variance and could be used to separate the samples into four distinct groups, according to high pressure treatment and packaging material. © 2008

Volatile compounds in dry-cured Serrano ham subjected to high pressure processing. Effect of the packaging material

The effect of high pressure treatment (400 MPa, 10 min at 12 °C) on the volatile profile of Spanish dry-cured Serrano ham, packaged with or without aluminum foil in a multilayer polymeric bag, was investigated. The analysis of the volatile fraction was carried out by dynamic headspace extraction coupled to gas chromatography-mass spectrometry. Pressure treatment only had a slight effect on the volatile fraction of Serrano ham. Most compounds affected by pressurization, such as alkanes (C9-C12), 2-undecene, 2-nonanone, 1-octen-3-one, 1-heptanol, 2-hexanol, 2-heptanol, ethyl pentanoate, benzaldehyde and styrene, presumably originated from the metabolism of moulds. A significant effect of pressurization on the migration of compounds from the plastic material was found. Linear and branched chain alkanes, alkenes as well as benzene compounds, were generally less abundant in pressurized samples than in untreated samples. A scalping effect was also observed for compounds such as butanal, pentanal, ethyl esters and pyrazines. © 2009 Elsevier Ltd. All rights reserved

Influence of compositional characteristics and high pressure processing on the volatile fraction of Iberian dry-cured ham after prolonged refrigerated storage

The effect of high pressure processing (HPP) at 600 MPa and refrigerated storage for 5 months on the volatile fraction of 30 Iberian dry-cured hams of different compositional characteristics was investigated. Compositional characteristics significantly influenced 11 compounds (3 alcohols, 3 carboxylic acids, 2 alkanes, 2 benzene compounds and 1 aldehyde) out of the 116 compounds identified in the volatile fraction of Iberian ham. HPP treatment had a significant effect on 34 volatile compounds, with higher levels of 11 compounds and lower levels of 23 compounds in HPP-treated samples than in control samples. Refrigerated storage for 5 months significantly influenced the levels of 75 compounds, 25 of which appeared or increased while 50 disappeared or decreased. During that period, the total abundance of volatile compounds decreased by 5.1% in control ham and 1.3% in HPP-treated ham. Iberian ham commercial shelf life should be limited to maintain its sensory characteristics. Industrial relevance: HPP treatment and refrigerated storage of dry-cured ham are advantageous industrial and commercial procedures. In the particular case of Iberian ham, both HPP and refrigerated storage brought about a decrease in the total levels of volatile compounds. Therefore, adequate HPP treatment conditions and commercial shelf life should be cautiously set in order to safeguard the unique odor and aroma characteristics of Iberian ham

Volatile compounds in low-acid fermented sausage "espetec" and sliced cooked pork shoulder subjected to high pressure processing. A comparison of dynamic headspace and solid-phase microextraction

Two extraction techniques, dynamic headspace extraction (DHE) and solid-phase microextraction (SPME), were compared to assess the effect of high-pressure treatment (400 MPa, 10 min, 12 °C) on the volatile compounds of low-acid fermented sausage "espetec" and sliced cooked pork shoulder stored at 4 °C. DHE was more efficient at extracting low-boiling compounds such as ethanal, 2,3-butanedione and alcohols, while SPME extracted more efficiently a higher number of chemical families, especially fatty acids. The effect of pressurisation on the volatile fraction of "espetec" was better categorized by DHE, whereas SPME was more appropriate for cooked pork shoulder. The volatile fraction of "espetec" changed slightly after pressurisation, mainly showing a decrease in the levels of lipid-derived compounds, like linear alkanes, aldehydes, or 1-alcohols in pressurised samples. The volatile profile of cooked pork shoulder underwent substantial changes during refrigerated storage, mainly due to microbial metabolism, most of these changes being limited by HPP. © 2011 Elsevier Ltd. All rights reserved

Effects of high-pressure processing on the volatile compounds of sliced cooked pork shoulder during refrigerated storage

The effect of high-pressure processing (pressure levels of 400, 500 and 600. MPa, and exposure times of 5 and 10. min) on the volatile profile of vacuum-packaged sliced cooked pork shoulder held for 28. days at 4 °C was assessed. The volatile fraction of pressurized samples scarcely changed immediately after treatment and remained stable for 14. days, regardless the pressure and time of exposure. After 21. days of storage, significant differences were observed in the profile of volatile compounds in pressurized samples as compared with control samples, these differences being treatment dependent. At the end of the storage period, control and 400. MPa samples showed higher levels of acetic and fatty acids, ethanol and ethyl esters, whereas 500 and 600. MPa samples contained higher levels of ethanal, branched-chain aldehydes, diacetyl, acetoin, and 2,3-butanediol among other compounds. These results suggest that the high-pressure treatment had a discriminant effect on the microbiota of cooked pork shoulder, which led to the accumulation of different volatile compounds during the refrigerated storage of control and pressurized samples. © 2010 Elsevier Ltd

Volatile compounds in ground beef subjected to high pressure processing A comparison of dynamic headspace and solid-phase microextraction

The effect on the volatile profile of cooked beef meat, previously subjected to high pressure (400. MPa, 10. min at 12 °C) followed by a 3-d refrigerated storage, was investigated by comparing two extraction techniques i.e. dynamic headspace and solid-phase microextraction. Dynamic headspace was more efficient in extracting 2,3-butanedione and secondary alcohols. Solid-phase microextraction, being more efficient in extracting substances such as 1-alcanols, ethyl esters and acids, permitted to better categorize the effects caused in the volatile fraction by refrigerated storage and high pressure processing. The volatile fraction of cooked control beef meat contained high amounts of diketones and low amounts of methyl ketones, secondary alcohols, aldehydes and fatty acids. While diketones nearly disappeared after the 3-d refrigerated storage, the other compounds together with ethanol and ethyl esters increased significantly. Pressurized beef samples underwent fewer changes than non-pressurized samples during refrigerated storage, leading to a volatile profile closer to that of control beef. © 2010 Elsevier Ltd