• Technologies for detecting PSE in pork

      Mullen, Anne Maria; McDonagh, Ciara; Troy, Declan J. (Teagasc, 2003-02)
      The ability of a single, on-line measurement to predict the quality status of an entire muscle or even of a whole carcass was investigated. Variation between pork muscles for on-line measurements of pH, conductivity and colour was evaluated. Intermuscular variation was detected at 24h p ostmortem with higher pH and conductivity values in the topside (M. s emimembranosus) than the striploin (M . longissimus thoracis et lumborum). Correlations showed that a relationship exists between the muscles (r = 0.46-0.88, p<0.05) at 45min and 3h p ostmortem. The location within the topside or the striploin at which the measurements were taken did not influence the result. Shackling did not introduce a significant variation between sides for pH, conductivity and colour values up to 24h p ostmortem, showing measurements could be taken on either side of the carcass.
    • Technology transfer of research results (The 2xtra project)

      McDonagh, Ciara; Byrne, Briege; Troy, Declan J.; Mullen, Anne Maria; Downey, Gerard; European Commission; European Union (Teagasc, 2008-02)
      The 2XTRA project (Technology Transfer Research Results Atlantic Area) was carried out with the aim of promoting economic activity based on research results and technologies developed within universities, research and technology institutes and companies in the European Atlantic Area. This collaborative work was carried out by a strong partnership of 13 entities across this region and included universities, research and technology institutes, private consultants and TBC (technology-based company) incubators. The specific goals of the project were: ● The exchange of information and experiences on technology transfer (TT) with a view to assisting project partners directly and feeding into their regional innovation systems. ● The promotion of new technology-based companies by drawing on collective experiences and developing methodologies relating to - identification and evaluation of business ideas - production of business plans, and - support of early stage companies internationalising. ● The creation of an Atlantic Area Network to support and promote technology-based companies (TBCs) and the technology transfer process. These objectives were achieved through defined activities carried out in three separate stages of this project.
    • Texture of fruit and vegetable components of ready meals

      Downey, Gerard (Teagasc, 2000-12)
      Vegetable and fruit purées are important parts of prepared ready-meals. Further expansion of this food sector will depend among other things on improved and consistent product quality. Innovative organoleptic properties in ready-meal components will assist in product diversification and the growth of market share.
    • Towards More Sustainable Meat Products: Extenders as a Way of Reducing Meat Content

      Pintado, Tatiana; Delgado-Pando, Gonzalo (MDPI AG, 2020-08-03)
      The low efficiency of animal protein (meat products) production is one of the main concerns for sustainable food production. However, meat provides high-quality protein among other compounds such as minerals or vitamins. The use of meat extenders, non-meat substances with high protein content, to partially replace meat, offers interesting opportunities towards the reformulation of healthier and more sustainable meat products. The objective of this review is to give a general point of view on what type of compounds are used as meat extenders and how they affect the physicochemical and sensory properties of reformulated products. Plant-based ingredients (pulses, cereals, tubers and fruits) have been widely used to replace up to 50% of meat. Mushrooms allow for higher proportions of meat substitution, with adequate results in reduced-sodium reformulated products. Insects and by-products from the food industry are novel approaches that present an opportunity to develop more sustainable meat products. In general, the use of meat extenders improves the yield of the products, with slight sensory modifications. These multiple possibilities make meat extenders’ use the most viable and interesting approach towards the production of healthier meat products with less environmental impact.
    • Transcriptome analysis of porcine M. semimembranosus divergent in intramuscular fat as a consequence of dietary protein restriction

      Hamill, Ruth M; Aslan, Ozlem; Mullen, Anne Maria; O'Doherty, John V.; McBryan, Jean; Morris, Dermot G.; Sweeney, Torres; Department of Agriculture, Food and the Marine, Ireland (Biomed Central, 06/07/2013)
      Background: Intramuscular fat (IMF) content is positively correlated with aspects of pork palatability, including flavour, juiciness and overall acceptability. The ratio of energy to protein in the finishing diet of growing pigs can impact on IMF content with consequences for pork quality. The objective of this study was to compare gene expression profiles of Musculus semimembranosus (SM) of animals divergent for IMF as a consequence of protein dietary restriction in an isocaloric diet. The animal model was derived through the imposition of low or high protein diets during the finisher stage in Duroc gilts. RNA was extracted from post mortem SM tissue, processed and hybridised to Affymetrix porcine GeneChip® arrays. Results: IMF content of SM muscle was increased on the low protein diet (3.60 ± 0.38% versus 1.92 ± 0.35%). Backfat depth was also greater in animals on the low protein diet, and average daily gain and feed conversion ratio were lower, but muscle depth, protein content and moisture content were not affected. A total of 542 annotated genes were differentially expressed (DE) between animals on low and high protein diets, with 351 down-regulated and 191 up-regulated on the low protein diet. Transcript differences were validated for a subset of DE genes by qPCR. Alterations in functions related to cell cycle, muscle growth, extracellular matrix organisation, collagen development, lipogenesis and lipolysis, were observed. Expression of adipokines including LEP, TNFα and HIF1α were increased and the hypoxic stress response was induced. Many of the identified transcriptomic responses have also been observed in genetic and fetal programming models of differential IMF accumulation, indicating they may be robust biological indicators of IMF content. Conclusion: An extensive perturbation of overall energy metabolism in muscle occurs in response to protein restriction. A low protein diet can modulate IMF content of the SM by altering gene pathways involved in lipid biosynthesis and degradation; however this nutritional challenge negatively impacts protein synthesis pathways, with potential consequences for growth.
    • Using induced chlorophyll production to monitor the physiological state of stored potatoes (Solanum tuberosum L.)

      Garnett, Jessica; Wellner, Nikolaus; Mayes, Andrew G; Downey, Gerard; Kemsley, E.K.; Teagasc Walsh fellowship Programme; Biotechnology and Biological Sciences Research Council, U.K.; 2014028 (Elsevier, 2018-08-04)
      A Visible/Near-infrared (Vis/NIR) spectrometer equipped with a fibre-optic probe was used to stimulate and measure chlorophyll production in potato tubers, at low levels that produce no visible greening in the skin. Subtle responses to changes in the light stimulus were also tracked. When used with a static experimental setup, these measurements are precise. However, the technique is very sensitive to the exact geometry of the tuber-probe arrangement, and careful positioning of the probe is crucial. Complementary studies established that tissue under the apical buds (‘eyes’) has greater capacity to produce chlorophyll than other locations on the tuber surface. A long-term study of multiple tubers suggested that different cultivars behave differently in terms of the rate of chlorophyll production. These behavioural differences may be related to the batch dormancy status; validating this potential relationship is the focus of ongoing work.
    • Using ultrasound to measure beef tenderness and fat content

      Allen, Paul; Dwyer, Catherine; Mullen, Anne Maria; Buckin, Vitaly; Smyth, Cormac; Morrissey, Siobhan (Teagasc, 2001-04)
      A new acoustical technique was developed for the quantitative analysis of the texture and composition of meat and meat products. This new approach exploits the fact that the acoustical velocity and attenuation of waves propagated through meat are affected by its mechanical properties, thus allowing characterisation in terms of its composition and eating quality. The method is based on a new high-resolution ultrasonic resonator. This technique is rapid and uses small samples. Procedures for the acoustical analysis of meat were developed and the results were correlated with taste panel and shear force measurements of meat tenderness.
    • Variation in the quality of meat from Irish steers at the time of slaughter.

      Moloney, Aidan P; Mullen, Anne Maria; Maher, S.C.; Buckley, D.J.; Kerry, Joseph P. (Teagasc, 01/01/2004)
      There is no information on the variation in quality, in particular tenderness, that exists in Irish Beef nor is there information on the variation that would remain if optimum practices were imposed at all stages of the beef production chain. Evaluation of the success of measures to improve beef consistency requires information on existing variation and the minimum variation achievable.The objectives of this project were (i) to establish the variation that exists in the quality of meat from Irish cattle, (ii) to quantify the minimum variation in meat quality that can be achieved in a practical beef production system, (iii) to determine the effects and mechanisms of additional sources of variation. The conclusions from this project are: • The M. longissimus dorsi (loin) was found to be more variable than the M. semimembranosus (topside) for most quality attributes examined (tenderness, sarcomere length and pH). The scale of variation within the loin was similar to that reported by the other research groups within the EU and US. Heifers were more variable than steers for most attributes, while there was no consistent classification effect on the variability of meat quality attributes. • Tenderness was equally variable in meat from genetically similar steers, managed similarly, compared to commercial steers randomly selected from a factory lairage but matched for weight and grade.This was likely a result of both groups being crossbred beef cattle of similar age, fat score, carcass weight and managed identically post-mortem. However, variation in tenderness of both groups was less than that observed in a survey of commercial throughput (experiment 1). This decrease is attributed to better pre-and-post-slaughter handling practices. • The data suggest that selection of sires (within a breed) with better than average conformation has no deleterious effect on the eating quality of beef of their progeny.A more comprehensive comparison of sires within a breed and between breeds is required to confirm the generality of this conclusion. • In a comparison of genotypes, gender and slaughter weights, there was no evidence that variation around the mean value for tenderness differed between breeds or liveweights after 14 days ageing. Bulls were more variable than steers for some quality traits but the variation in tenderness was similar for bulls and steers after 14 days ageing. • While optimising the management of animals during the pre and post-slaughter period reduced variation in tenderness, some residual variation remained. A large percentage of the residual variation in tenderness (Warner Bratzler shear force) after 2 and 7 days post-mortem was explained by proteolysis (breakdown of myofibrillar proteins).Variation in tenderness (Warner Bratzler shear force) after 2 days post-mortem was largely explained by phosphates (energy) and proteolysis, while sensory tenderness was largely explained by phosphates and glycolytic potential. • Further work is required to reduce residual variation in Irish beef and to determine the causes of this variation.
    • What are the drivers of beef sensory quality using metadata of intramuscular connective tissue, fatty acids and muscle fiber characteristics?

      Listrat, Anne; Gagaoua, Mohammed; Andueza, Donato; Gruffat, Dominique; Normand, Jérome; Mairesse, Guillaume; Picard, Brigitte; Hocquette, Jean-François; Agence de l'Environnement et de la Maîtrise de l'Energie, France; European Union; et al. (Elsevier BV, 2020-10)
      The aim of this integrative study was to investigate the relationships between biochemical traits (total, insoluble and soluble collagens (TCol, ICol, SCol), cross-links (CLs), proteoglycans (TPGs), proportion of fiber types, total lipids (TLips), main fatty acids (FAs) families, the n-6/n-3 polyunsaturated FA (n-6/n-3PUFA) ratio and the sensory attributes scores (tenderness, juiciness, flavor) of two muscles from beef: Rectus abdominis (RA) and Longissimus thoracis (LT). For robust analysis, a database was prepared using samples from three studies from animals raised under different production systems. The analyses were performed either on each study separately or on pooled data per muscle after removing as many experimental effects as possible in each study. The CLs (across the muscles and studies) and, to a lower extent, type IIA muscle fibers (mainly for RA muscles), saturated FAs (SFAs), monounsaturated FAs (MUFAs) (for the LT muscles) were the components the most frequently associated with tenderness. The CLs, type IIA muscle fibers (mainly for the RA muscles), TLips, SFAs, MUFAs, conjugated linoleic acids (CLAs) and n-6/n-3 PUFA ratio (mainly for the LT muscles) were the components the most associated with juiciness. The TLips and CLAs (across the muscles and studies), SFAs, MUFAs (mainly for the LT muscles), CLs (mainly for the RA muscles) and TPGs (mainly for the LT muscles) were the components the most associated with flavor liking. The CLs, CLAs, TLips, SFAs, MUFAs, n-6/n-3 PUFA ratio, type IIA and I muscle fibers were the components the most frequently associated with the 3 sensory scores taken together. The SCol, TPGs and type IIX+B muscle fibers were little associated with the sensory scores taken together. The TCol, ICol and PUFAs were components the least associated with sensory scores. The data of this integrative study highlighted for the first time that the CLs were negatively involved in the determination of the three sensory traits mainly in the RA muscle. The muscle fibers in this integrative study had a weak impact on the variations in beef sensory traits. The type IIA and IIX+B muscle fibers were respectively negatively and positively associated with tenderness, negatively associated with juiciness and flavor. The type I muscle fibers were overall positively associated with juiciness and flavor and negatively or positively with tenderness and these associations were muscle and study-dependent. Overall, the TLips and FAs were positively associated with the sensory scores and the n-6/n-3 PUFA ratio was negatively associated with them.
    • What are the drivers of beef sensory quality using metadata of intramuscular connective tissue, fatty acids and muscle fiber characteristics?

      Listrat, Anne; GAGAOUA, Mohammed; Andueza, Donato; Gruffat, Dominique; Normand, Jérome; Mairesse, Guillaume; Picard, Brigitte; Hocquette, Jean-François; Agence de l'Environnement et de la Maîtrise de l'Energie; European Union; et al. (Elsevier, 2020-08-14)
      The aim of this integrative study was to investigate the relationships between biochemical traits (total, insoluble and soluble collagens (TCol, ICol, SCol), cross-links (CLs), proteoglycans (TPGs), proportion of fiber types, total lipids (TLips), main fatty acids (FAs) families, the n-6/n-3 polyunsaturated FA (n-6/n-3PUFA) ratio and the sensory attributes scores (tenderness, juiciness, flavor) of two muscles from beef: Rectus abdominis (RA) and Longissimus thoracis (LT). For robust analysis, a database was prepared using samples from three studies from animals raised under different production systems. The analyses were performed either on each study separately or on pooled data per muscle after removing as many experimental effects as possible in each study. The CLs (across the muscles and studies) and, to a lower extent, type IIA muscle fibers (mainly for RA muscles), saturated FAs (SFAs), monounsaturated FAs (MUFAs) (for the LT muscles) were the components the most frequently associated with tenderness. The CLs, type IIA muscle fibers (mainly for the RA muscles), TLips, SFAs, MUFAs, conjugated linoleic acids (CLAs) and n-6/n-3 PUFA ratio (mainly for the LT muscles) were the components the most associated with juiciness. The TLips and CLAs (across the muscles and studies), SFAs, MUFAs (mainly for the LT muscles), CLs (mainly for the RA muscles) and TPGs (mainly for the LT muscles) were the components the most associated with flavor liking. The CLs, CLAs, TLips, SFAs, MUFAs, n-6/n-3 PUFA ratio, type IIA and I muscle fibers were the components the most frequently associated with the 3 sensory scores taken together. The SCol, TPGs and type IIX+B muscle fibers were little associated with the sensory scores taken together. The TCol, ICol and PUFAs were components the least associated with sensory scores. The data of this integrative study highlighted for the first time that the CLs were negatively involved in the determination of the three sensory traits mainly in the RA muscle. The muscle fibers in this integrative study had a weak impact on the variations in beef sensory traits. The type IIA and IIX+B muscle fibers were respectively negatively and positively associated with tenderness, negatively associated with juiciness and flavor. The type I muscle fibers were overall positively associated with juiciness and flavor and negatively or positively with tenderness and these associations were muscle and study-dependent. Overall, the TLips and FAs were positively associated with the sensory scores and the n-6/n-3 PUFA ratio was negatively associated with them.