Perceptions of PDO Beef: The Portuguese Consumer

The objectives of this paper are to examine consumers' perceptions of Protected Designation of Origin (PDO) beef on the basis of a survey of consumers and buyers of beef. The paper identifies a profile of PDO beef consumers, examines their behaviour and perceptions on PDO beef, derives the dimensions of perceptions of PDO beef, and establishes segments based upon those dimensions. The results reveal that PDO consumers are representative of all geographical regions, age and profession groups, are lighter consumers of beef and shop for food mainly in the butchers. Consumers' perceptions on PDO beef emphasises quality, safety, and control. However, underlying those perceptions are six main dimensions and it is possible to identify three segments of PDO beef consumers: a faithful consumer group, an unaware consumer group, and a sensory, price conscious group.Protected designations of origin, beef, perceptions, factor analysis, cluster analysis, Consumer/Household Economics,

Climate-informed stochastic hydrological modeling: Incorporating decadal-scale variability using paleo data

A hierarchical framework for incorporating modes of climate variability into stochastic simulations of hydrological data is developed, termed the climate-informed multi-time scale stochastic (CIMSS) framework. A case study on two catchments in eastern Australia illustrates this framework. To develop an identifiable model characterizing long-term variability for the first level of the hierarchy, paleoclimate proxies, and instrumental indices describing the Interdecadal Pacific Oscillation (IPO) and the Pacific Decadal Oscillation (PDO) are analyzed. A new paleo IPO-PDO time series dating back 440 yr is produced, combining seven IPO-PDO paleo sources using an objective smoothing procedure to fit low-pass filters to individual records. The paleo data analysis indicates that wet/dry IPO-PDO states have a broad range of run lengths, with 90% between 3 and 33 yr and a mean of 15 yr. The Markov chain model, previously used to simulate oscillating wet/dry climate states, is found to underestimate the probability of wet/dry periods >5 yr, and is rejected in favor of a gamma distribution for simulating the run lengths of the wet/dry IPO-PDO states. For the second level of the hierarchy, a seasonal rainfall model is conditioned on the simulated IPO-PDO state. The model is able to replicate observed statistics such as seasonal and multiyear accumulated rainfall distributions and interannual autocorrelations. Mean seasonal rainfall in the IPO-PDO dry states is found to be 15%-28% lower than the wet state at the case study sites. In comparison, an annual lag-one autoregressive model is unable to adequately capture the observed rainfall distribution within separate IPO-PDO states. Copyright © 2011 by the American Geophysical Union.Benjamin J. Henley, Mark A. Thyer, George Kuczera and Stewart W. Frank

Climate-informed stochastic hydrological modeling: Incorporating decadal-scale variability using paleo data

A hierarchical framework for incorporating modes of climate variability into stochastic simulations of hydrological data is developed, termed the climate-informed multi-time scale stochastic (CIMSS) framework. A case study on two catchments in eastern Australia illustrates this framework. To develop an identifiable model characterizing long-term variability for the first level of the hierarchy, paleoclimate proxies, and instrumental indices describing the Interdecadal Pacific Oscillation (IPO) and the Pacific Decadal Oscillation (PDO) are analyzed. A new paleo IPO-PDO time series dating back 440 yr is produced, combining seven IPO-PDO paleo sources using an objective smoothing procedure to fit low-pass filters to individual records. The paleo data analysis indicates that wet/dry IPO-PDO states have a broad range of run lengths, with 90% between 3 and 33 yr and a mean of 15 yr. The Markov chain model, previously used to simulate oscillating wet/dry climate states, is found to underestimate the probability of wet/dry periods >5 yr, and is rejected in favor of a gamma distribution for simulating the run lengths of the wet/dry IPO-PDO states. For the second level of the hierarchy, a seasonal rainfall model is conditioned on the simulated IPO-PDO state. The model is able to replicate observed statistics such as seasonal and multiyear accumulated rainfall distributions and interannual autocorrelations. Mean seasonal rainfall in the IPO-PDO dry states is found to be 15%-28% lower than the wet state at the case study sites. In comparison, an annual lag-one autoregressive model is unable to adequately capture the observed rainfall distribution within separate IPO-PDO states. Copyright © 2011 by the American Geophysical Union.Benjamin J. Henley, Mark A. Thyer, George Kuczera and Stewart W. Frank

Enhanced product recovery from glycerol fermentation into 3-carbon compounds in a bioelectrochemical system combined with in situ extraction

Given the large amount of crude glycerol formed as a by-product in the biodiesel industries and the concomitant decrease in its overall market price, there is a need to add extra value to this biorefinery side stream. Upgrading can be achieved by new biotechnologies dealing with recovery and conversion of glycerol present in wastewaters into value-added products, aiming at a zero-waste policy and developing an economically viable process. In microbial bioelectrochemical systems (BESs), the mixed microbial community growing on the cathode can convert glycerol reductively to 1,3-propanediol (1,3-PDO). However, the product yield is rather limited in BESs compared with classic fermentation processes, and the synthesis of side-products, resulting from oxidation of glycerol, such as organic acids, represents a major burden for recovery of 1,3-PDO. Here, we show that the use of an enriched mixed-microbial community of glycerol degraders and in situ extraction of organic acids positively impacts 1,3-PDO yield and allows additional recovery of propionate from glycerol. We report the highest production yield achieved (0.72 mol1,3-PDO mol−1glycerol) in electricity-driven 1,3-PDO biosynthesis from raw glycerol, which is very close to the 1,3-PDO yield reported thus far for a mixed-microbial culture-based glycerol fermentation process. We also present a combined approach for 1,3-PDO production and propionate extraction in a single three chamber reactor system, which leads to recovery of additional 3-carbon compounds in BESs. This opens up further opportunities for an economical upgrading of biodiesel refinery side or waste streams

Redox functionality mediated by adsorbed oxygen on a Pd-oxide film over a Pd(100) thin structure: A first-principles study

Stable oxygen sites on a PdO film over a Pd(100) thin structures with a (sqrt{5} times sqrt{5}) R27^circ surface-unit cell are determined using the first-principles electronic structure calculations with the generalized gradient approximation. The adsorbed monatomic oxygen goes to a site bridging two 2-fold-coordinated Pd atoms or to a site bridging a 2-fold-coordinated Pd atom and a 4-fold-coordinated Pd atom. Estimated reaction energies of CO oxidation by reduction of the oxidized PdO film and N_2O reduction mediated by oxidation of the PdO film are exothermic. Motion of the adsorbed oxygen atom between the two stable sites is evaluated using the nudged elastic band method, where an energy barrier for a translational motion of the adsorbed oxygen may become sim 0.45 eV, which is low enough to allow fluxionality of the surface oxygen at high temperatures. The oxygen fluxionality is allowed by existence of 2-fold-coordinated Pd atoms on the PdO film, whose local structure has similarity to that of Pd catalysts for the Suzuki-Miyaura cross coupling. Although NO_x (including NO_2 and NO) reduction is not always catalyzed only by the PdO film, we conclude that there may happen continual redox reactions mediated by oxygen-adsorbed PdO films over a Pd surface structure, when the influx of NO_x and CO continues, and when the reaction cycle is kept on a well-designed oxygen surface.Comment: 15 pages, 6 figures, submitted to J. Phys. Condens. Matte

Public Labeling Revisited: The Role of Technological Constraints Under Protected Designation of Origin Regulation

This paper takes into account technological and output constraints for firms to analyse PDO regulation. We first examine an original dataset of French Brie cheese producers and compare the cost structure of PDO producers with non-PDO ones. The paper also finds that PDO firms face a more costly production technology and do not profit from scale economies. Then, based on a theoretical model, the paper shows a clear tradeoff between the sunk advertising costs (net of certification costs) and the degree of diseconomies of scale. This tradeoff affects both the firms' incentive to certify, and the efficiency of public certification.Agricultural and Food Policy,

MaxDiff approaches for PDO “Calanda” peaches (Spain)

Peaches with PDO Calanda are one of the 20 fruits with PDO existing in Spain. The aim of this work is to understand how consumers make their choices based on the most important peaches’ attributes and levels. In this work, 4 attributes with 3 levels in each attribute have been considered (price: 1.5 €/kg, 2.5 €/kg and 3.5 €/kg; origin: PDO Calanda, non PDO Calanda and non Calanda; packaging: bulk, conventional packaging and active packaging; and fruit size: small, medium and big). Four Best-Worst (BW) exploded models have been utilised, two of them with scale factors. All those models have been compared to two traditional Discrete Choice (DC) models. Results show that traditional DC models have better performance than the other models and the best model is when consumers select the best option. Within the exploded models, the choice sequence decisions starting from worst options are better than those which start from best option. Consumers prefer PDO Calanda peaches over other types and the positive difference in their Willingness to Pay (WTP) are more or less the same between peaches from Calanda with PDO and without PDO as it is between the latter and peaches coming from other origins.best-worst, exploding models, consumer behavior, choice experiment, fruit quality., Agricultural and Food Policy,

Quality Choice, Competition and Vertical Relationship in a Market of Protected Designation of Origin

Protected Designation of Origin (PDO) is a public label that is used by the European Union as a tool to sustain the competitiveness and the profitability of agricultural sector and in particular to maintain rural activity in less favored areas. However, in PDO supply chain, many farmers deal with relatively few processing firms. In this framework, it is not clear that producers under such protective policy would have incentive to adopt costly measures to improve their product qualities and accept the restrictions on their production practices. Taking into account the vertical structure of the PDO supply chain, we develop a model of oligopoly and oligopsony competition to investigate the conditions under which PDO producers set high quality requirements on the production of the agricultural input. We find that even if raising quality does not imply additional willingness to pay from consumers, there is still scope for the PDO producers to choose a higher level of quality than the minimum quality standard. The outcome depends on the demand and technology characteristics, which will affect the oligopoly and oligopsony power of processors. In particular, farmers will prefer a higher quality standard than processors when the demand for PDO market is inelastic and the increase in quality generates an additional reduction in farmers’ return to scale.Marketing,

Raising rivals’ costs strategy: test on two LAFS in Europe

Some Localised Agro-Food Systems (LAFS) are traditionally qualified as success stories (Comté PDO in France, Gruyere PDO in Switzerland, Parmigiano Reggiano PDO in Italy), whilst other PDOs (as for example the Cantal PDO from France) pay the same price for the milk as standard milk. The price difference may reach between 10 and 25% over a long period. To explain this difference, we assume that the agents who make up the LAFS developed a collective action to protect their localized cheese production system against unfair competition and to promote their product outside its region of origin. The aim of this communication is to shed light on levers which the agents activate to assure their uniqueness is irrevocable, and uphold the benefits of their LAFS. We propose to discuss the idea that the search for market power based on the strategy of raising rivals’ costs may be used even outside a situation of vertical integration or a situation in which pressure is applied to suppliers to challenge competitors. We assume that some companies within the LAFS have sufficient control on the rules governing the organization of the traditional system to benefit from it. They also succeed in protecting a kind of relationship between business companies. The Raising Rivals’ Costs theory helps to analyze the economic consequences of the legal set-up implementation and of its control by some companies. Indeed, we show that the collective control of the rules which are set up in the PDO legal framework explain the difficulties met by rivals to stand out through an alternative and independent production system based on the costs leadership strategy. The collective set up of institutions and rules help the agents to achieve a collective competitive advantage in which every agent benefits individually. This is the strategy developed in Europe and particularly for two PDO Localised Agro-cheese Systems: Comté PDO for France and Gruyère PDO for Switzerland.PDO, localised agro-food system, Raising rivals’ costs, regulation, Agribusiness, Agricultural and Food Policy, Community/Rural/Urban Development, Food Consumption/Nutrition/Food Safety, Labor and Human Capital,

High yield 1,3-propanediol production by rational engineering of the 3-hydroxypropionaldehyde bottleneck in Citrobacter werkmanii

Background: Imbalance in cofactors causing the accumulation of intermediates in biosynthesis pathways is a frequently occurring problem in metabolic engineering when optimizing a production pathway in a microorganism. In our previous study, a single knock-out Citrobacter werkmanii Delta dhaD was constructed for improved 1,3-propanediol (PDO) production. Instead of an enhanced PDO concentration on this strain, the gene knock-out led to the accumulation of the toxic intermediate 3-hydroxypropionaldehyde (3-HPA). The hypothesis was emerged that the accumulation of this toxic intermediate, 3-HPA, is due to a cofactor imbalance, i.e. to the limited supply of reducing equivalents (NADH). Here, this bottleneck is alleviated by rationally engineering cell metabolism to balance the cofactor supply. Results: By eliminating non-essential NADH consuming enzymes (such as lactate dehydrogenase coded by ldhA, and ethanol dehydrogenase coded by adhE) or by increasing NADH producing enzymes, the accumulation of 3-HPA is minimized. Combining the above modifications in C. werkmanii Delta dhaD resulted in the strain C. werkmanii Delta dhaD Delta ldhA.adhE::ChlFRT which provided the maximum theoretical yield of 1.00 +/- 0.03 mol PDO/mol glycerol when grown on glucose/glycerol (0.33 molar ratio) on flask scale under anaerobic conditions. On bioreactor scale, the yield decreased to 0.73 +/- 0.01 mol PDO/mol glycerol although no 3-HPA could be measured, which indicates the existence of a sink of glycerol by a putative glycerol dehydrogenase, channeling glycerol to the central metabolism. Conclusions: In this study, a multiple knock-out was created in Citrobacter species for the first time. As a result, the concentration of the toxic intermediate 3-HPA was reduced to below the detection limit and the maximal theoretical PDO yield on glycerol was reached