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Utilisation of a Portable Electronic Nose, NeOse Pro, to Follow the Microbial Fermentation of a Yoghurt
No full textInternational audienceYoghurt is fermented milk which results from the exclusive action of Lactobacillus delbrueckii subsp bulgaricus and Streptococcus thermophilus. However, a disruption of the bacterial growth can lead to significant industrial losses. Currents monitoring methods, based on the checking of the pH during the fermentation step are not always satisfactory. The NeOse Pro system, a portable electronic nose, is a mean to obtain immediately aromatic profiles. In this work, we applied this technology to the yoghurt ecosystem, a highly hydrated product. The profiles obtained allowed us to discriminate yoghurts before and after fermentation. In detail, the discrepancy between the two bacteria cultured alone was slight. It was also the case when we compared different initial bacterial ratios. However, two different mixes of bacteria led to clearly distinguishable profiles. A GC/MS analysis performed on products fermented 7 h allowed us to explain the detection of acetaldehyde by the stimulation of some captors of the apparatus. NeOse Pro is so convenient to study the fermentation of yogurt
OPALE: a Framework for Assessing the Eco-functionalities of Landscapes
No full textInternational audienceEcohydrological processes are of primary importance in agricultural landscapes where fluxes of water are driven by vegetation, whether cultivated in fields or grasslands or present in semi-natural habitats and interstitial areas (open channels, riparian borders, inter-ranks of perennial crops) surrounding the cultivated parcels. Human practices are a key lever of the composition and properties of vegetation in landscape agroecosystems. In order to better understand their impact, we propose a suite of Gama and Matlab programs coupled in a single OPALE-gui (OPerational Assessment of Landscapes Eco-functionalities) that aims at (i) representing landscape organization in relation with the functioning and decision rules of annual crops or breeding systems, (ii) evaluating water movements and trajectories from biomass and hydrological exchanges, and (iii) analyzing the transfer dynamics of nutrients, suspended matter or fecal bacteria based on particle tracking methods. More precisely, the tool includes a set of libraries about: • the distribution of the farmland part of the landscape, allowing to spatially allocate crops into farm fields and the related farming practices (inputs, soil tillage, fodder management...) following time schedules (Land Use and Land Cover Change model, LULCC); • the modeling of water movements within previous simulated landscapes, considering surface, sub-surface and deep flows (Water Movements Within Landscapes model, WMWL); • the evaluation of –inert and living– solute and suspended matter transfers related to water movements, including N, P, E. Coli (EC) and Suspended Matter (SM); • the construction of output normalized indicators of landscape function in order to assess its regulation service. OPALE allows to better understand the underlying processes that drive exchanges and sink-source effects operating at the landscape scale, including a landscape transfer function and a delivery ratio for the global assessment of landscapes. It was tested in three agricultural contexts and biophysical situations. Water flows and flows of associated matters were compared to data recorded at the catchment outlet, and showed the efficiency of the algorithms developed in the generic OPALE libraries
Définition d'un cadre d'ingénierie à base de modèles pour la conception et le pilotage des systèmes agroalimentaires de proximité
No full textInternational audienceThe objective of this project is to produce knowledge on hybrid food systems between short and long circuits, on their economic, social and environmental performances, on the conditions of their sustainability, in order to co-construct with the partner actors of the projecta method and support tools for their sustainable development. These systems are particularly complex: interaction between actors, interaction between performance indicators of various kinds, new vocabulary and new practices centered on human relationships with very little formalization. To tackle this problem, we propose to use some system engineering approaches based on meta-modeling, both at the level of flows, as well as requirements as well as performance indicators. After presenting the problem, we will detail our approach as well as its implementation. We will end with a review and outlook.L'objectif de ce projet est de produire des connaissances sur les systèmes alimentaires hybrides entre circuits courts et circuits longs, sur leurs performances économiques, sociales et environnementales, sur les conditions de leur durabilité, afin de co-construire avec les acteurs partenaires du projet une méthode et des outils d'accompagnement pour leur développement durable. Ces systèmes s'avèrent particulièrement complexes : interaction entre acteurs, interaction entre indicateurs de performance de nature diverse, nouveau vocabulaire et nouvelles pratiques centrées sur les rapports humains avec très peu de formalisation. Pour aborder ce problème, nous proposons d'utiliser certaines approches issues de l'ingénierie système basée sur la méta-modélisation, tant au niveau des flux, que des exigences ainsi que des indicateurs de performances. Après avoir présenté la problématique, nous détaillerons notre approche ainsi que sa mise en oeuvre. Nous terminerons par un bilan et des perspectives. ABSTRACT. The objective of this project is to produce knowledge on hybrid food systems between short and long circuits, on their economic, social and environmental performances, on the conditions of their sustainability, in order to co-construct with the partner actors of the project a method and support tools for their sustainable development. These systems are particularly complex: interaction between actors, interaction between performance indicators of various kinds, new vocabulary and new practices centered on human relationships with very little formalization. To tackle this problem, we propose to use some system engineering approaches based on meta-modeling, both at the level of flows, as well as requirements as well as performance indicators. After presenting the problem, we will detail our approach as well as its implementation. We will end with a review and outlook. MOTS-CLÉS. Système alimentaire de proximité, ingénierie système, méta-modélisation, diagramme des exigences, indicateurs de performance
Nanoencapsulation of Essential Oils as Natural Food Antimicrobial Agents: An Overview
No full textInternational audienceThe global demand for safe and healthy food with minimal synthetic preservatives is continuously increasing. Natural food antimicrobials and especially essential oils (EOs) possess strong antimicrobial activities that could play a remarkable role as a novel source of food preservatives. Despite the excellent efficacy of EOs, they have not been widely used in the food industry due to some major intrinsic barriers, such as low water solubility, bioavailability, volatility, and stability in food systems. Recent advances in nanotechnology have the potential to address these existing barriers in order to use EOs as preservatives in food systems at low doses. Thus, in this review, we explored the latest advances of using natural actives as antimicrobial agents and the different strategies for nanoencapsulation used for this purpose. The state of the art concerning the antibacterial properties of EOs will be summarized, and the main latest applications of nanoencapsulated antimicrobial agents in food systems will be presented. This review should help researchers to better choose the most suitable encapsulation techniques and materials
Bringing sustainable urban planning down to earth through food: the experience of the food transects of Grenoble and Caen
No full textInternational audienceOur contribution aims at pointing out how the food issue challenges metropolitan areas while at the same time identifying potential for sustainable urban planning. To that end, we investigate to what extent taking into account agricultural and food-related issues enables to rethink urban planning which is usually qualified as sustainable. Our analysis will be based upon the two French urban regions of Grenoble and Caen where participatory research was conducted through collective and prospective walks. These urban explorations, which provide insights on metropolitan spaces and the interrelations that underlie them, underly the disconnections of contemporary urban planning with the inhabitants, their vital needs and, more generally, the soil, while highlight working paths for a more nourishing, meaningful and rooted urban planning. By considering urban planning through the scope of agri-food stakes, we contribute then to the renewal of urban concepts and thus highlight three workshops aiming at further developing sustainable urban planning issues and tools
ISARA Lyon : Peut-on pratiquer du semis direct sous couvert végétal sans herbicide ?
No full textInternational audienceLa technique du semis direct sous couvert végétal (SDSC) développée en agriculture de conservation (AC) protège et améliore la fertilité des sols. Cependant avec l'interdiction du glyphosate ou en agriculture biologique la méthode n'est pas durable. Compte rendu d'expérimentations exploratoires menées dans le cadre d'un doctorat avec l'ISARA en Auvergne-Rhône-Alpes où il apparaît la nécessité de développer des outils adaptés à de fortes biomasses présentes sur le sol en absence de recours aux herbicides
C’est le retour du « maire nourricier », les collectivités territoriales réorganisent la disponibilité de l'offre alimentaire
No full textEntretien avec Caroline BRAND. Propos recueillis par Juliette Démas.Spécialiste des systèmes et politiques alimentaires territoriales, enseignante-chercheuse en géographie à l'ISARA, Caroline Brand analyse les dynamiques qui émergent dans l'urgence de la crise et invite à penser leur pérennisation
Le développement de filières locales est-il gage d’une écologisation des pratiques agricoles ?
No full textInternational audienceAccording to the literature on short local food systems, the direct relationship between consumers and producers triggers a virtuous circle that relies upon shared trust. What happens when the relationship is no longer direct but mediated by a small number of intermediaries? Socio-technical processes of changing agricultural practices are questionned by analysing the emergence of two local food chains in the Auvergne Rhône Alpes region: local soybean and minced steaks. Enrollment in a local food chain does not necessarily imply that producers adopt more agro-ecological practices. Nonetheless practices considered as environmental friendly are valued by local food chains. Sociotechnical objects or food chain governance have the potential to question farmers practices and invite to move the focus on long term learning processes.Selon la littérature sur les circuits courts, la relation directe entre consommateurs et producteurs enclenche un cercle vertueux de confiance partagée. Qu’advient-il lorsque la relation n’est plus directe mais médiée par un petit nombre d’intermédiaires dans des filières qui revendiquent une dimension locale ?L’analyse de la mise en place de deux filières de la région Auvergne-Rhône-Alpes, soja local et steaks hachés, nous permet de saisir les processus socio-techniques fins d’écologisation des pratiques agricoles. La construction de ces filières locales, dans leur phase d’émergence, n’entraine pas d’écologisation des pratiques mais valorise des pratiques jugées plus écologiques. En l’absence des consommateurs dans la gouvernance de ces filières, les objets techniques mobilisés ou la gouvernance mise en place ont la capacité de réinterroger les pratiques des agriculteurs et invitent à placer la focale sur les apprentissages dans le temps long
Medium‐term evolution in French national newspaper coverage of the interrelations between biodiversity and agriculture
No full textInternational audienceAgricultural landscapes are sites of difficult trade-offs between conservation and production objectives. The media play a part in shaping public opinion and policies and vice-versa. In line with the constructionist approach to public problems, we analyzed the role of media in the problem-framing of interrelations between biodiversity and agriculture. We investigated the medium-term evolution in French national newspaper coverage of these interrelations using a content and time analysis over a 19-year period (1999–2017). We applied a statistical method using IRaMuTeQ (interface of R) on seven daily newspapers (Le Monde, Libération, La Croix, Les Échos, Le Figaro, L'Humanité, and La Tribune; N = 2,547). Our results reveal the growing importance of agriculture in the public problem of biodiversity loss. The increase of agriculture/biodiversity coverage is driven by environmental issues and specific political events. However, the number of articles focused on biodiversity/agriculture dynamics remains low. Around 2007, the articles shifted from an international speciescentered view to a national and local human-centered view. These evolutions in media-coverage create a space for ecologists, social scientists, and agronomists to combine their approaches and to develop and communicate on new actions in favor of biodiversity in agricultural landscapes