Supranutritional doses of vitamin E to improve lamb meat quality

Vitamin E is a fat-soluble antioxidant, therefore, it can be stored in any fat depot in the body, where it exerts a potent chain-breaking antioxidant effect. Moreover, the antioxidant activity of vitamin E-like compounds is also present in meat post mortem. The deposition of tocopherol in the muscle depends on the dosage, the source, and the period of supplementation, so different dosage-time combinations have been developed. Vitamin E does not affect production parameters if minimum requirements for function and growth are satisfied, but it could influence lamb fatty acid profile. During display, it protects PUFA from degradation, reducing lipid oxidation and, therefore, delaying discolouration. Furthermore, vitamin E would indirectly affect the development of lamb aroma by reducing protein and lipid oxidation. To facilitate optimal supplementation rates by producers and retailers, the present paper reviews vitamin E chemistry, biochemistry, nutrition and its ability to maintain lamb quality

Analizando los resultados académicos en la Educación Superior en España

The development of the European Higher Education Area has been a process of modernization in many universities. Teaching methodologies have undergone a process of continuous change to meet the demands for high quality leading to a need for enhancement in the learning assessment methodologies as well. The objective of this study is to analyse student´s academic performance measured through coursework vs. final exam and to ascertain the factors that could explain the difference. Regression and variance analysis are carried out over the grades and responses to a questionnaire on a sample of 298 students of different subjects in a Spanish university. The results show that there are differences between continuous assessment and the final examination marks.Ministerio de Economía y Competitividad FFI2013-41235-

Efecto de la inclusión de semilla de lino y CLA en la dieta sobre la aceptabilidad de la carne de vacuno

Publishe

Aceptabilidad de la carne de terneros alimentados con semilla de lino y ácido linoleico conjugado protegido

Se presentan los resultados de un trabajo sobre el efecto que tiene en la aceptabilidad de los consumidores de carne de vacuno madurada durante 7 y 21 días, la inclusión en la dieta de los animales de semilla de lino y ácido linoleico conjugado protegido (CLA)Publishe

Number of consumers and days of display necessary for the assessment of meat colour acceptability

Visual assessment is regarded as the gold standard to evaluate meat colour shelf-life, but it is costly and time consuming. To address this issue, this paper aims to evaluate the number of consumers and days of display that are necessaries in order to assess the colour shelf-life of meat, presented with different methods, all using images. Photographs of thirty-six lamb steaks were taken just after cutting (day 0) and on each of the following days until the 14th day of display under standardized conditions. Images were presented in three different manners: 1) with days of display and animals in random order (Random); 2) days of display in sequential and animals in random order (Sequential); and, 3) days of display and animals in sequential order (Animal); they were presented to 211 consumers who evaluated visual acceptability on a 9-point scale. At day zero, visual acceptability scores were the highest in Animal, followed by Sequential, and then by the Random (P <.05) method. Scores decreased over time for all methods tested (P <.05). The Random method presented the highest standard deviation; however, an increase in standard deviation among consumers along days of display was observed for all methods tested (P <.05). Shelf-life determined by regression varied according to the method of presentation (7.83, 7.00 and 7.54 days for Random, Sequential and Animal, respectively). A minimum number of 4 day points before and 4 day points after neutral scores had been reached (scores = 5.0) were necessary in order to obtain a robust model. The minimum number of required consumers (a = 0.05; d = 0.1 and ß = 0.2 or 0.1) varied according to methodology: it was 81 to 109 consumers for Random, 69 to 92 for Sequential, and 55 to 74 for Animal. Our study indicates that an optimal number of days and evaluators can be calculated depending on the manner of sample presentation. These findings should be taken into account in further studies that aim to balance data reliability with the cost involved in meat colour analyses

Stability analysis for the background equations for inflation with dissipation and in a viscous radiation bath

The effects of bulk viscosity are examined for inflationary dynamics in which dissipation and thermalization are present. A complete stability analysis is done for the background inflaton evolution equations, which includes both inflaton dissipation and radiation bulk viscous effects. Three representative approaches of bulk viscous irreversible thermodynamics are analyzed: the Eckart noncausal theory, the linear and causal theory of Israel-Stewart and a more recent nonlinear and causal bulk viscous theory. It is found that the causal theories allow for larger bulk viscosities before encountering an instability in comparison to the noncausal Eckart theory. It is also shown that the causal theories tend to suppress the radiation production due to bulk viscous pressure, because of the presence of relaxation effects implicit in these theories. Bulk viscosity coefficients derived from quantum field theory are applied to warm inflation model building and an analysis is made of the effects to the duration of inflation. The treatment of bulk pressure would also be relevant to the reheating phase after inflation in cold inflation dynamics and during the radiation dominated regime, although very little work in both areas has been done, the methodology developed in this paper could be extended to apply to these other problems.Comment: 27 pages, 14 figures, Published version JCA

Validation of photographs usage to evaluate meat visual acceptability of young bulls finished in feedlot fed with or without essential oils

Forty ½ Brown Swiss × ½ Nellore crossbred bulls were distributed into three experimental groups: CON – diet without addition of essential oils; CLO – diet with average 5, 000 mg/animal/day of clove essential oils and CIN – diet with average 5, 000 mg/animal/day of cinnamon essential oils to evaluate three methodologies of visual acceptability: with steaks directly in Trays and Sequential and Random photos. Seventeen consumers evaluated visual appearance of meat using a 9-point structured hedonic scale. CON group presented higher shelf-life than essential oils groups. Trays and Sequential scores were similar in the majority of days; thus digital images could be used to evaluate colour evolution. However, Random photos resulted in lower scores and slower acceptability decrease than Trays and Sequential photos (p < 0.05) among the second and fifth day of display. Random photos presented a lower and more constant standard deviation than Trays and Sequential photos (p < 0.01) indicating that this methodology promoted a higher standard situation for meat colour evaluation

Calidad de carne de 7 razas españolas de ganado bovino vinculadas a su sistema de producción

En 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. En: https://calidadcarnecita.wordpress.com/2016/02/12/calidad-de-la-carne-de-7-razas-espanolas-vinculadas-a-sus-sistema-de-produccion

Shear viscous effects on the primordial power spectrum from warm inflation

We compute the primordial curvature spectrum generated during warm inflation, including shear viscous effects. The primordial spectrum is dominated by the thermal fluctuations of the radiation bath, sourced by the dissipative term of the inflaton field. The dissipative coefficient \Upsilon, computed from first principles in the close-to-equilibrium approximation, depends in general on the temperature T, and this dependence renders the system of the linear fluctuations coupled. Whenever the dissipative coefficient is larger than the Hubble expansion rate H, there is a growing mode in the fluctuations before horizon crossing. However, dissipation intrinsically means departures from equilibrium, and therefore the presence of a shear viscous pressure in the radiation fluid. This in turn acts as an extra friction term for the radiation fluctuations that tends to damp the growth of the perturbations. Independently of the T functional dependence of the dissipation and the shear viscosity, we find that when the shear viscous coefficient \zeta_s is larger than 3 \rho_r/H at horizon crossing, \rho_r being the radiation energy density, the shear damping effect wins and there is no growing mode in the spectrum.Comment: 18 pages, 6 figure