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Discrimination of spoiled beef and salmon stored under different atmospheres by an optoelectronic nose. Comparison with GC-MS measurements
No full textInternational audienceThe aim of this study was to evaluate the capacity of an electronic nose, the NeOse Pro, to assess the alteration of two food matrixes of animal origin, beef and salmon. For each matrix, two types of samples were analyzed, natural samples and simplified "diluted " samples based on meat juice and agar. Samples were inoculated with specific spoilage organisms and stored for 6 days at 8°C under different conditions: air, modified atmosphere packaging, and vacuum packaging. A non-inoculated control sample was stored at-80°C under vacuum packaging. Results of the NeOse Pro were compared with gas chromatography coupled to mass spectrophotometry analysis. For this purpose, heatmaps, principal component analysis and discriminant analysis were used. GC-MS results show that the major detected volatile organic compounds for beef stored under air are dimethyl disulfide and ethyl acetate. For salmon stored under air, it was mainly dimethyl disulfide, methyl thioacetate, acetoin and ethyl acetate that were produced. For beef and salmon NeOse Pro and GC-MS results are consistent; samples stored under air are separated from other samples
Reduced tillage in organic farming affects soil organic carbon stocks in temperate Europe
No full textInternational audienceFor decades, conservation tillage has been promoted as a measure to increase carbon stocks in arable soils. Since organic farming improves soil quality and soil carbon storage, reduced tillage under organic farming conditions may further enhance this potential. Therefore, we assessed soil organic carbon (SOC) stocks of reduced tillage compared with mouldboard ploughing in nine organic farming field trials in France, Germany, the Netherlands, and Switzerland with the same sampling and analytical protocol. We sampled soil cores until a depth of 100 cm to determine soil carbon stocks that are relevant for climate change mitigation but are often overlooked in tillage studies with shallow sampling depths. The studied field experiments were between 8 and 21 years old and comprised different soil types with clay contents ranging from 10% to 50%. SOC stocks increased with increasing clay-to-silt ratio, precipitation and organic fertiliser input. Across sites, reduced tillage in comparison with ploughing increased SOC stocks in the surface layer (0-10/15 cm) by 20.8% or 3.8 Mg ha − 1 , depleted SOC stocks in the intermediate soil layers to 50 cm soil depth with a maximum depletion of 6.6% or 1.6 Mg ha − 1 in 15/ 20-30 cm and increased SOC stocks in the deepest (70-100 cm) soil layer by 14.4% or 2.5 Mg ha − 1. The subsoil SOC stock increase may be linked to the inherent soil heterogeneity. Cumulative SOC stocks increased by 1.7% or 1.5 Mg ha − 1 (0-50 cm, n = 9) and 3.6% or 4.0 Mg ha − 1 (0-100 cm, n = 7) by reduced tillage compared with ploughing with estimated mean C sequestration rates of 0.09 and 0.27 Mg ha − 1 yr − 1 , respectively. There was no effect of field trial duration on tillage induced cumulative SOC stocks differences. Under reduced tillage, biomass production was 8% lower resulting in a decrease of crop C input by 6%. However, this reduction may have been outbalanced by increased C inputs from weed biomass resulting from a higher weed incidence in reduced tillage, which warrants further research. Thus, reduced tillage in organic farming has the potential to increase total SOC stocks, while crop management has to be improved to increase productivity
Pesticide contamination of fish ponds in relation to crop area in a mixed farmland-pond landscape (Dombes area, France)
No full textInternational audiencePesticides are still widely used by agriculture, leading to the exposure of surface water. This may be the case for fish ponds located in farmland landscapes. To address this issue, the present study investigated the contamination by pesticides of fish ponds located in the mixed agriculture-pond landscape of the Dombes area, France. Ten ponds were selected in water catchments with a gradient of 3–57 ha of cropland with maize and winter cereals as the dominant crops. A total of 197 water samples were collected in the ponds during the fish production season over 3 years. Recently used pesticides were the most frequent residues occurring. Occurrences greater than 0.1 µgL−1 particularly concerned chlorotoluron and S-metolachlor. Maximum observed concentrations were slightly above 3 µgL−1 for S-metolachlor, acetochlor, and dimethenamide, all herbicides allowed for maize cultivation. Isoproturon and chlorotoluron, herbicides allowed in cereal crops, reached up to 1.2 and 1.0 µgL−1, respectively. We found a significant positive effect of crop area in catchments on the pond contamination frequency by pesticides and more significantly on the contamination frequency by broad-spectrum herbicides (glyphosate and AMPA residues). The cumulative antecedent rainfall was best correlated to the frequency of highest contaminations (> 0.5 µgL−1). In such a hydrological context, the crop area within catchment was identified as a good indicator of fish pond exposure to pesticide residues. Finally, we proposed to adapt some mitigation measures to reduce fish pond contamination
Perception of cultured “meat” by French consumers according to their diet
No full textInternational audienceThe culture of muscle cells for food purposes, so-called cultured "meat", is advertised by its proponents as likely to meet the growing demand for animal protein without the disadvantages of animal farming. However, while this product is still in development and not yet widely commercialised, it is already attracting various forms of criticism from consumers. The present study follows a large international online survey of 5418 consumers in France which was aimed at understanding consumer perceptions of muscle cell culture for food purposes. Based on 118 interviews conducted on volunteers with specific dietary habits (vegans, vegetarians, flexitarians, regular meat consumers), the aim of this study was to target an audience with a variety of diets and thus to analyse more closely consumers' feelings towards this product. Regular meat consumers are more favourable to this product than vegetarians and vegans whose convictions prevent them from tasting artificial "meat". The consumption of this new product would be perceived by the latter as a step backwards. Of the 118 people questioned, half of them think that this product could have a negative impact on the animal industry, 41% fear undesirable health effects and 29% do not believe in the quality of this product. However, this new product arouses curiosity amongst the respondents, the majority of whom (80%) would like to try it. While the selling price of this product is questionable, 22% of respondents indicated that they had no intention of buying it. For those who were likely to buy this product, prices were expected to be lower or equal to those of conventional meat for 72% of them. Despite the uncertainties regarding its future development, the majority of respondents were optimistic about the future of this product. 80% of them believe it will become widespread more or less quickly, whether they like it or not, mainly because French people's mentalities are changing, despite that fact that the implementation of this product would appear difficult on certain points. The vegans are more likely to be neutral than the other consumers. There is no consensus on the term "meat" for this new foodstuff, with 25% of those questioned agreeing with the term "cultured meat" (14%) in particular. The majority of flexitarians (55%) are opposed to the use of the term "meat" for this new product, whereas this term seems to be suitable for 91% of the vegans and 82% of the vegetarians. The semantic issue is important and the name of this new product must not mislead the consumer
Public awareness of organic agriculture: creation of the 1st MOOC on organic farming in Europe
No full textSource Agritrop Cirad (https://agritrop.cirad.fr/599242/)International audienceGiven the many sources of information available on organic agriculture (OA), it is difficult for the public to build an opinion. The first, francophone MOOC on organic farming and food (MOOC BIO) was built to provide updated information on the development status and challenges of OA and to allow as many people as possible to build an objective and informed opinion on OA. For 8 weeks, a broad range of themes (regulation, stakeholders, history, production techniques, marketing systems and territorial development) were addressed. Almost 20,000 students have participated to the MOOC, with large international coverage, illustrating the great interest paid to OA. In addition, the organization of events around the MOOC has broadened the target audience. Through a partnership with OA stakeholders in Senegal we even reached an international dimension. For wider dissemination, translation into others languages is a perspective. Background: The development and media coverage of organic farming has resulted in the wide dissemination of information on organic farming and food. Anyone can learn about organic farming by browsing the wide internet. However, the diversity in nature and quality related to this information and also controversies between researchers (See for instance the debate after the publication In Nature Searchinger et al., 2018) may lead to some confusion and misinformation for the general public. Organic farming stakeholders, citizens and consumers need to form a critical opinion on some of the issues raised by the OA: what is the right price for organic products? Are organic products better for human and environmental health? In the digital age, the MOOC BIO (Massive Open Online Course on OA) aims to support this public in building informed opinion on organic agriculture. To our knowledge, this is the first MOOC dedicated to organic agriculture, started in 2018. Core messages and conclusions: The main messages are: - Two MOOC sessions have already unfolded in 2018 and 2019, and attracted almost 20,000 participants coming from more than 100 countries. This underlines the interest that OA represents for learners, citizens, consumers and organic farming actors. - The MOOC addresses seven dimensions of organic agriculture, namely: regulation, stakeholders, history, production techniques, marketing systems linked to consumption and territorial development. The deepening of controversial cross-cutting issues (OA and biodiversity; OA and prices; OA and human health; OA and water), based on selected resources and promoting exchanges between registered participants (thanks to forums and collective synthesis work) enriched the participants' positioning. The learners were also led to develop a reflexive approach on the evolution of their representations of OA, between the beginning and the end of the MOOC training. - The cross-disciplinary of this MOOC was made possible thanks to the diversity of the authors' fields of expertise (Figure1). It has led to the creation of a network around organic farming in higher education in France - The construction of an informed opinion on learners' organic farming was built thanks to the original structure of the MOOC: a more transmitted part (although punctuated by varied activities) and another part where knowledge is co-constructed by the participants (Figure 2). - This online training also includes meetings in France (between MOOC participants and organic farming actors) via surveys that participants carried out or via events organized by MOOC authors. - The dissemination of the knowledge developed in the MOOC has also reached a wider audience through events organised by the MOOC's designers: Interventions with high school students (“Fête de la science” event), the resources produced have also been used in face-to-face training for future agricultural engineers in France. - International collaborations (with actors of agroecology in Senegal and with the CIRAD) enable us to propose resources outside the European context. 111 -A further perspective is to translate this MOOC into several languages (English and Spanish) for the next sessions in order to increase its international visibility
Les produits laitiers locaux face à l'industrialisation de la filière-lait (1950-1980)
No full textInternational audienceLe beurre, produit phare de la modernisation- Une « industrialisation » exemplaire en Bretagne ?- Des résistances autour de l’arôme, de la valorisation des crus régionaux et de valorisation des savoir-faireLe saint-nectaire, une AOC au carrefour de deux modèles agricoles- 1955, la consécration éphémère d’un saint-nectaire uniquement fermier- Le saint-nectaire fermier : du monopole à la marginalisation- Une cohabitation des modèles pour une gouvernance en perpétuelle évolutio
: Le cas de la vallée de la Vanne et de la ville de Paris
No full textInternational audienceL’agriculture biologique (AB) est considérée comme une solution pertinente aux problèmes de pollution des ressources en eau. Dans cet article, nous nous appuyons sur le projet mené par la ville de Paris dans la vallée de la Vanne pour analyser comment une agglomération peut développer un projet de développement de l’AB à l’échelle d’une aire d’alimentation de captages et engager un changement de fonds de l’agriculture afin de pérenniser son approvisionnement en eau potable. Nous retraçons la trajectoire de ce projet et montrons que différents outils et échelles d’action ont été mobilisés pour mettre en lien l’enjeu eau potable avec d’autres comme celui de l’alimentation via l’approvisionnement de cantines en produits biologiques
Food Sovereignty and Rights-Based Approaches Strengthen Food Security and Nutrition Across the Globe: A Systematic Review
No full textInternational audienceThis systematic review assembles evidence for rights-based approaches–the right to food and food sovereignty–for achieving food security and adequate nutrition (FSN). We evaluated peer-reviewed and gray literature produced between 1992 and 2018 that documents empirical relationships between the right to food or food sovereignty and FSN. We classified studies by literature type, study region, policy approach (food sovereignty or right to food) and impact (positive, negative, neutral, and reverse-positive) on FSN. To operationalize the concepts of food sovereignty and the right to food and connect them to the tangible interventions and practices observed in each reviewed study, we also classified studies according to 11 action types theorized to have an impact on FSN; these included “Addressing inequities in land access and confronting the process of land concentration” and “Promoting gender equity,” among others. We found strong evidence from across the globe indicating that food sovereignty and the right to food positively influence FSN outcomes. A small number of documented cases suggest that narrow rights-based policies or interventions are insufficient to overcome larger structural barriers to realizing FSN, such as inequitable land policy or discrimination based on race, gender or class