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As ageing process is one of the main factors influencing the organoleptic characteristics of meat and its consumer acceptability, the objective of this research was to study the organoleptic attributes variation of meat from Asturiana de los Valles and Retinta breeds at two times of the ageing process (7 and 14 days) under different pre-slaughter transport conditions (mixing and non-mixing with unfamiliar animals). A descriptive sensory analysis was carried out with a trained panel and the acceptability and preference for ageing meat of these two breeds were analysed with 75 consumers, as well as a study on the factors that influence the purchase decision to this type of meat. The breed and mixing with unfamiliar animals before slaughter affected significantly at instrumental tenderness. The intensity of the attributes related to the texture showed significant differences among studied samples at 7 days of ageing, with an increase in tenderness, juiciness and fibrousness while at 14 days of ageing, odour, beef flavour, liver flavour and smoothness also showed significant differences. The results indicated that the organoleptic attributes changed in intensity during ageing time, therefore, we can conclude that the attributes of tenderness, juiciness, smoothness, fibrousness, odour, beef flavour and liver flavour showed significant differences among samples and could be considered sensory indicators of ageing. The type of pre-slaughter transport (with or without mixing with unknown animals) also influenced the intensity of the sensory attributes, but less markedly than the breed effect. It was also observed that consumers prefer the meat of the Asturiana de los Valles breed aged for 14 days, despite among the factors that most influence the meat purchase decision, the ageing time was not present. Regarding purchasing habits, a relationship was observed between the meat purchase format and sale point. Overall, it is necessary to promote greater knowledge among consumers about the importance of ageing in beef quality., Este trabajo fue financiado por el proyecto RTA 2014-00034-C00 (INIA-AEI) y fondos FE- DER

The objective of this work was to demonstrate how the extraction method affects the reliability of biomarker detection and how this detection depends on the biomarker location within the cell compartment. Different extraction methods were used to study the sarcoplasmic and myofibrillar fractions of the Longissimus thoracis et lumborum muscle of young bulls of the Asturiana de los Valles breed in two quality grades, standard (Control) or dark, firm, and dry (DFD) meat. Protein extractability and the expression of some of the main meat quality biomarkers—oxidative status (lipoperoxidation (LPO) and catalase activity (CAT)), proteome (SDS-PAGE electrophoretic pattern), and cell stress protein (Hsp70)—were analyzed. In the sarcoplasmic fraction, buffers containing Triton X-100 showed significantly higher protein extractability, LPO, and higher intensity of high-molecular-weight protein bands, whereas the TES buffer was more sensitive to distinguishing differences in the protein pattern between the Control and DFD meat. In the myofibrillar fraction, samples extracted with the lysis buffer showed significantly higher protein extractability, whereas samples extracted with the non-denaturing buffer showed higher results for LPO, CAT, and Hsp70, and higher-intensity bands in the electrophoretic pattern. These findings highlight the need for the careful selection of the extraction method used to analyze the different biomarkers considering their cellular location to adapt the extractive process.

espanolEn el ganado vacuno, el estres pre-sacrificio provoca la aparicion de carnes conocidas como DFD (Dark,Firm, Dry), que se identifican por un descenso anomalo del pH muscular post-mortemy que muestranserios problemas de calidad, lo cual disminuye su valor comercial. El objetivo de este trabajo es conocerlas diferencias en los procesos de estres oxidativo, en los mecanismos de supervivencia/muerte celular(autofagia/apoptosis) y en biomarcadores proteomicos a las 24 h post-mortem,entre canales que mos-traron un descenso normal de pH (pH = 5,4-5,8 a las 24 h post-mortem) utilizadas como CONTROL y ca-nales con pH a las 24 h post-mortem(pH24) > 6,0 clasificadas como DFD, con el fin de identificar los pro-cesos del metabolismo muscular ligados a la aparicion de carnes DFD.Se analizo el estres oxidativo celular mediante el estudio de la actividad antioxidante total y los danosen macromoleculas (proteinas y lipidos). Las carnes DFD mostraron mayor actividad antioxidante (P EnglishIn cattle, pre-slaughter stress causes the appearance of DFD (Dark, Firm, Dry) beef, with defective post-mortemmuscle pH decline and detrimental quality that reduce its commercial value. This paper aimsto study differences in oxidative stress, cell survival or death mechanisms (autophagy/apoptosis) and proteomic biomarkers at 24 h post-mortembetween beef carcasses with normal pH decline (pH = 5.4-5.8at 24 h post-mortem) used as CONTROL and carcasses with pH at 24 h hours post-mortem(pH24)> 6.0classified as DFD, in order to understand the relevant changes on the early post-mortemmuscle me-tabolism related to the DFD occurrence.Cell oxidative stress was analyzed as total antioxidant activity and damage of macromolecules (proteinsand lipids). The results showed that DFD meat had increased muscle antioxidant activity (P

Animal management practices may influence the animal's susceptibility to stress, with detrimental effects on the ultimate meat quality. In this field, proteomics is a promising tool that reveals the biological pathways underpinning the effect of animal's pre-slaughter stress (PSS) on the ultimate meat quality. The objective of this work was to study the effect of a pre-slaughter procedure that may promote stress, such as mixing unfamiliar animals during the transport and lairage period, on the post-mortem muscle proteome of young bulls reared under two different farm management systems (Intensive or Extensive). Comparative proteomics and biochemical analysis reveal the effect of PSS on biochemical pathways involved in the meat colour development, muscle redox status, energy metabolism and autophagy. This work highlights the potential of some muscle proteins such as Beclin-1 (autophagy marker), CKM (biomarker of energy transduction) and proteins of the energy metabolism (ALDOA, PYGM, PGM1, PKM, GPI) as potential biomarkers to discriminate beef samples according to the incidence of PSS. SIGNIFICANCE: Meat scientists are interested in the study of individual animal-based measurements that allow the detection of stress situations which could have negative effects on meat quality. In this context, the mechanisms underlying the adverse effects of pre-slaughter stress on the post-mortem muscle metabolism need to be elucidated in order to understand how animal stress may influence the conversion of muscle into meat. In this work, the study of proteome changes in the post-mortem muscle has allowed the identification of significant biomarkers of these processes that could be used as tools for detecting inappropriate strategies that may induce increased animal stress and, in consequence, may compromise the ultimate beef quality.

A method for the rational design of molecularly imprinted polymers with catalytic activity (MICs) that mimic hemeproteins is described. Density Functional Theory calculations applied to the pre-polymerization adduct and to a possible reaction intermediate allow to choose the best functional monomer that builds up the active sites. This functional monomer should stabilize both relevant stages, the first one in an adequate porogenic solvent and the second one in the aqueous reaction medium. In this work, a MIC was synthesized to catalyze the oxidation of 2,4,6-trichlorophenol (TCP), the substrate and template molecule. A hemin molecule was used as the catalytic centre and four functional monomers and six solvents were tested. According to the theoretical predictions, methacrylamide and 4-vinylpyridine MIPs successfully mimic the recently discovered ability of Chloroperoxidase (CPO) to catalyze the oxidative dechlorination of TCP in batch analysis. They exhibit good catalytic properties and substrate selectivity.

Work has commenced on the study and characterization of wood native species (oak, chestnut, cherry, alder, ash, and beech), employed to a minor extent in enology, for their application in the elaboration of distillates. To this end, furanic and low molecular weight phenol compounds, total phenolic content, and antioxidant activity in alcoholic extracts by maceration of wood chips at 2 toasting levels were studied. Significant differences between samples, technologically relevant, were due both to species and toasting time. Furthermore, extracts showed interesting antioxidant activities equivalent in some cases to than those reported for alcoholic beverages aged in wood.

Methanolic and acetonic extracts of apple pomace were evaluated for phenolic profiles, antioxidant properties and antiviral effect against herpes simplex virus type 1 (HSV-1) and 2 (HSV-2). Acetone extraction yielded the higher amounts of phenolic compounds. The extraction method influenced the phenolic composition although antioxidant activity correlated weakly with phenols concentration. Among the polyphenols analysed, quercetin glycosides were the most important family, followed by dihydrochalcones. Apple pomace extracts were able to inhibit both HSV-1 and HSV-2 replication in Vero cells by more than 50%, at non-cytotoxic concentrations. Selectivity indexes (SI) ranged from 9.5 to 12.2.

Eleven different cider apple pomaces (six single-cultivar and five from the cider-making industry) have been analysed for low molecular phenolic profiles and antioxidant capacity. The Folin index ranged between 2.3 and 15.1 g gallic acid per kg of dry matter. Major phenols were flavanols, dihydrochalcones (phloridzin and phloretin-2′-xyloglucoside), flavonols and cinnamic acids (chlorogenic and caffeic acids). The group of single-cultivar pomaces had higher contents of chlorogenic acid, (-)-epicatechin, procyanidin B2 and dihydrochalcones, whereas the industrial samples presented higher amounts of up to four unknown compounds, with absorption maxima between 256 and 284 nm. The antioxidant capacity of apple pomace, as determined by the DPPH and FRAP assays, was between 4.4 and 16.0 g ascorbic acid per kg of dry matter, thus confirming that apple pomace is a valuable source of antioxidants. PLSR analysis gave reliable mathematical models which allowed to predict the antioxidant activity of apple pomace as a function of the phenolic profile. The variables with the higher modelling power were phloridzin > procyanidin B2 > rutin + isoquercitrin > protocatechuic acid > hyperin.

Forty-four Asturian ciders were analysed for total phenolic content, phenolic profiles, and antioxidant capacity by the FRAP and the DPPH radical assays. The Folin index of ciders ranged between 446 and 1180 mg gallic acid/L. The phenolic profile of Asturian cider is mainly constituted by phenolic acids, flavan-3-ols, volatile phenols and dihydrochalcones. The methods to determine the antioxidant activity of ciders were optimised in terms of suitable reaction times, within-day and between-day repeatability. Thus, time courses of ciders in the DPPH and the FRAP assays were performed. Mean values for antioxidant activity of cider, expressed in ascorbic acid equivalents were 2.9 mM (as determined by the DPPH assay). When the FRAP assay was used, the antioxidant capacity of cider increased with the reaction time from 3.8 mM (4 min) to 5.4 mM (40 min). Multivariate approaches based on phenolic composition can be useful to predict the antioxidant capacity of cider. Folin index and flavanols and hydrocaffeic acid contents were the best predictors for antioxidant activity.

The antiherpes virus properties of Phyllanthus orbicularis Kunth, a Cuban-endemic medicinal plant, have been reported previously but data on its phytochemical profile and identification of antiviral metabolites as well as their mechanisms of action are still lacking. In this work, a bioactivity-guided phytochemical analysis was performed in order to isolate anti HSV-2 compounds. P. orbicularis contained mainly phenolic acids derivatives and flavonoids. The antiviral effects were attributed to (-)-epicatechin-3-O-gallate (EC(50) = 11.7 µg/mL), procyanidins B1 and B2 (EC(50) = 32.8 µg/mL and 24.2 µg/mL, respectively) as well as oligomeric and polymeric procyanidins and their gallate derivatives. The antiviral mechanisms of the active P. orbicularis extracts and fractions were also investigated and the inhibition of several HSV-2 early replication events and DNA synthesis were observed. This is the first study of extensive fractionation and phytochemical characterization of phenolic compounds from this species.

The antiherpes virus properties of Phyllanthus orbicularis Kunth, a Cuban-endemic medicinal plant, have been reported previously but data on its phytochemical profile and identification of antiviral metabolites as well as their mechanisms of action are still lacking. In this work, a bioactivity-guided phytochemical analysis was performed in order to isolate anti HSV-2 compounds. P. orbicularis contained mainly phenolic acids derivatives and flavonoids. The antiviral effects were attributed to (-)-epicatechin-3-O-gallate (EC(50) = 11.7 µg/mL), procyanidins B1 and B2 (EC(50) = 32.8 µg/mL and 24.2 µg/mL, respectively) as well as oligomeric and polymeric procyanidins and their gallate derivatives. The antiviral mechanisms of the active P. orbicularis extracts and fractions were also investigated and the inhibition of several HSV-2 early replication events and DNA synthesis were observed. This is the first study of extensive fractionation and phytochemical characterization of phenolic compounds from this species.

A methodology based on density functional theory calculations for the design of molecularly imprinted polymers (MIPs) is described. The method allows the rational choice of the most suitable monomer and polymerization solvent among a set of chemicals traditionally used in MIP formulations for the molecular imprinting of a given template. It is based on the comparison of the stabilization energies of the prepolymerization adducts between the template and different functional monomers. The effect of the polymerization solvent is included using the polarizable continuum model. A voltammetric sensor for homovanillic acid was constructed using different MIPs as recognition element, confirming that the solvent (toluene) and functional monomer (methacrylic acid) selected according to the theoretical predictions lead to the most efficient molecular recognition sensing phase. With the voltammetric sensor prepared using the MIP designed according to the theoretical predictions, a linear response for concentrations of homovanillic acid between 5 x 10(-8) and 1 x 10(-5) M can be obtained. The limit of detection is 7 x 10(-9) M. The selectivity obtained for homovanillic acid over other structurally related compounds buttresses the validity of this strategy of design.

Density Functional Theory calculations have been used to select, among a set of chemicals traditionally used in the formulation of non-covalent molecularly imprinted polymers (MIPs), the best functional monomer and porogenic solvent for the construction of a recognition element for the dopamine metabolite homovanillic acid (HVA). Theoretical predictions were confirmed through batch binding assays and voltammetric detection. The computational method predicts that trifluoromethacrylic acid and toluene are the monomer and solvent rendering the highest stabilization energy for the pre-polymerization adducts. HVA-MIP prepared using this formulation gives rise to a binding isotherm that is accurately modelled by the Freundlich isotherm. The binding properties of this polymer were estimated using affinity distribution analysis. An apparent number of sites of 13 micromol g(-1) with an average affinity constant of 2 x 10(4) M(-1) was obtained in the concentration window studied.