Lipid Oxidation and Sensory Characteristics of Grass-Fed Beef: Effect of Duration of Grazing Prior to Slaughter

Beef from cattle produced from grass has a higher concentration of fatty acids considered to be beneficial to human health than beef produced from more intensive production systems and this increase in fatty acid concentration is dependant on the duration at pasture prior to slaughter (Noci et al., 2003). Improvements in the fatty acid composition of beef must not impair other quality characteristics of beef. Little information is available on the pattern of change of quality characteristics in grazing animals. The objective of this study was to determine the shelf-life and eating quality of beef from cattle produced from a standard Irish grass silage/concentrates finishing system but allowed to graze grass for different periods prior to slaughter

Defeasible Logic: Agency, Intention and Obligation

We propose a computationally oriented non-monotonic multi-modal logic arising from the combination of agency, intention and obligation. We argue about the defeasible nature of these notions and then we show how to represent and reason with them in the setting of defeasible logic

Comparative concept similarity over Minspaces: Axiomatisation and Tableaux Calculus

We study the logic of comparative concept similarity \CSL introduced by Sheremet, Tishkovsky, Wolter and Zakharyaschev to capture a form of qualitative similarity comparison. In this logic we can formulate assertions of the form " objects A are more similar to B than to C". The semantics of this logic is defined by structures equipped by distance functions evaluating the similarity degree of objects. We consider here the particular case of the semantics induced by \emph{minspaces}, the latter being distance spaces where the minimum of a set of distances always exists. It turns out that the semantics over arbitrary minspaces can be equivalently specified in terms of preferential structures, typical of conditional logics. We first give a direct axiomatisation of this logic over Minspaces. We next define a decision procedure in the form of a tableaux calculus. Both the calculus and the axiomatisation take advantage of the reformulation of the semantics in terms of preferential structures.Comment: 25 page

BIO Logical Agents: Norms, Beliefs, Intentions in Defeasible Logic

In this paper we follow the BOID (Belief, Obligation, Intention, Desire) architecture to describe agents and agent types in Defeasible Logic. We argue, in particular, that the introduction of obligations can provide a new reading of the concepts of intention and intentionality. Then we examine the notion of social agent (i.e., an agent where obligations prevail over intentions) and discuss some computational and philosophical issues related to it. We show that the notion of social agent either requires more complex computations or has some philosophical drawbacks

Normative Autonomy and Normative Co-ordination: Declarative Power, Representation, and Mandate

In this paper we provide a formal analysis of the idea of normative co-ordination. We argue that this idea is based on the assumption that agents can achieve flexible co-ordination by conferring normative positions to other agents. These positions include duties, permissions, and powers. In particular, we explain the idea of declarative power, which consists in the capacity of the power-holder of creating normative positions, involving other agents, simply by "proclaiming" such positions. In addition, we account also for the concepts of representation, namely the representative's capacity of acting in the name of his principal, and of mandate, which is the mandatee's duty to act as the mandator has requested. Finally, we show how the framework can be applied to represent the contract-net protocol. Some brief remarks on future research and applications conclude this contribution

The use of visible and near infrared reflectance spectroscopy for prediction and improvement of meat quality characteristics in beef

Contributed to: 60th Annual Meeting of the European Association for Animal Production. Book of abstracts No. 15 (Barcelona, Spain, 24-27 August 2009).A slaughter trial was carried out to identify improved measurement techniques for meat eating and carcass quality in beef. Data on 194 steer and heifer beef cattle from rotational crosses of Aberdeen Angus and Limousin were available. Meat eating quality characteristics measured were sensory traits (tenderness, flavour, juiciness and abnormal flavour, 14 days post mortem (pm)), instrumental tenderness (slice shear force, 3 days pm; Volodkevitch 10 days pm), fatty acid profiles (saturated and unsaturated fatty acids, 48 h pm), colour (48 h pm) and cooking loss (14 days pm). Visible and near infrared reflectance spectroscopy (Vis-NIR) measurements were taken in the abattoir on the M. longissimus thoracis between 12th/13th ribs at 48 h pm over the spectral range from 350 to 1,800 nm. Partial least square regression was used for prediction of meat eating quality traits from Vis-NIR spectra. Measurements of Vis-NIR showed correlations with sensory traits of 0.45 (juiciness) to 0.77 (flavour), physical measurements of 0.61 (Volodkevitch) and 0.74 (slice shear force), fatty acids in the range from 0.49 to 0.80, colour of 0.93 (red-green) to 0.95 (yellow-blue) and cooking loss of 0.60. The results indicate that based on the measurements of Vis-NIR spectra online in the abattoir, it was possible to successfully predict numerous (mostly lowly correlated) meat quality characteristics. This shows the high variation in absorption at different Vis-NIR wavelengths due to factors such as muscular fibre characteristics, chemical bonds and colour, which are associated with various meat quality characteristics. Generally, the results support the use of on-line Vis-NIR in the abattoir for early, fast and relatively inexpensive estimation of beef meat quality and its use in value based marketing systems and genetic improvement programmes.Peer reviewe

On-line prediction of the fatty acid content of beef meat by near infrared reflectance spectroscopy

1 page, 1 figure.--The Proceedings of the British Society of Animal Science constitute summaries of papers presented at the Society's Annual Conference (Southport, UK, 30 March-1 April 2009).The amount and fatty acid (FA) composition of beef intramuscular fat (IMF) are key factors that influence technological and sensory quality, especially shelf-life (lipid and pigment oxidation) and flavour. Furthermore, consumers are interested in the fat composition of meat, as nutritional guidelines are recommending a lower saturated FA (SFA) intake due to its association with cardiovascular diseases. The amount and composition of ruminant IMF, which depends on factors such as the genetic origin of the animals, feeding regime, age or live weight, influences the final quality of the product, which also explains the increasing interest in defining the FA profile of meat. However, quantitative chemical techniques for the determination of FA involve extraction of total lipids and determination of FA methyl esters by gas chromatography, so that this procedure is costly, time-consuming and generates hazardous waste. The use of near infrared reflectance spectroscopy (NIR) is increasing in food analysis because it offers several advantages over conventional methods, giving fast, non-destructive, clean and cost effective measurements. Therefore, the aim of this study was to test the on-line estimation of the concentration of major individual FA (C16:0, C18:0 and C18:1) and main groups of FA (SFA, monounsaturated FA (MUFA) and polyunsaturated FA (PUFA)) of beef IMF using NIR, by direct application of a fibreoptic probe to the M. longissimus thoracis with no prior sample treatment.We are grateful to the Scottish Government for funding the research and Scotbeef, QMS, BCF and Signet for their substantial support.Peer reviewe