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Nanoemulsion-Based Multilayer Films for Ground Beef Preservation: Antimicrobial Activity and Physicochemical Properties
No full textInternational audienceThis study aimed to improve the physical, mechanical, and biological properties of a monolayer pectin (P) film containing nanoemulsified trans-Cinnamaldehyde (TC) by incorporating it between inner and outer layers of ethylcellulose (EC). The nanoemulsion had an average size of 103.93 nm and a zeta potential of −46 mV. The addition of the nanoemulsion increased the opacity of the film, reduced its moisture absorption capacity, and improved its antimicrobial activity. However, the tensile strength and elongation at break of the pectin films decreased after the incorporation of nanoemulsions. Multilayer films (EC/P/EC) showed a higher resistance to breaking and better extensibility compared to monolayer films. The antimicrobial activity of both mono and multilayer films was effective in inhibiting the growth of foodborne bacteria during storage of ground beef patties at 8 °C for 10 days. This study suggests that biodegradable antimicrobial multilayer packaging films can be effectively designed and applied in the food packaging industry.Cette étude visait à améliorer les propriétés physiques, mécaniques et biologiques d'un film monocouche de pectine (P) contenant du trans-cinnamaldéhyde (TC) nanoémulsifié en l'incorporant entre les couches internes et externes d'éthylcellulose (EC). La nanoémulsion avait une taille moyenne de 103,93 nm et un potentiel zêta de -46 mV. L'ajout de la nanoémulsion a augmenté l'opacité du film, réduit sa capacité d'absorption de l'humidité et amélioré son activité antimicrobienne. Cependant, la résistance à la traction et l'élongation à la rupture des films de pectine ont diminué après l'incorporation des nanoémulsions. Les films multicouches (EC/P/EC) ont montré une plus grande résistance à la rupture et une meilleure extensibilité que les films monocouches. L'activité antimicrobienne des films monocouches et multicouches a permis d'inhiber la croissance des bactéries d'origine alimentaire pendant le stockage de galettes de bœuf haché à 8 °C pendant 10 jours. Cette étude suggère que les films d'emballage multicouches biodégradables et antimicrobiens peuvent être conçus et appliqués efficacement dans l'industrie de l'emballage alimentaire
OUTILLAGE -Des outils pour accompagner les agriculteurs dans l'innovation en ferme
No full textCe numéro réunit les publications liées aux programmes de développement agricole et rural (PNDAR). Ces projets sont financés par le Compte d’affectation spéciale développement agricole et rural (CASDAR) 2017National audienceThe agroecological transition of farms requires an in-depth change in advisory approaches, placing the farmer at the centre of a co-innovation and adaptive management approach. In this context, the main objective of the OUTILLAGE project was to close the gap in operational resources to support these new approaches, by developing tools to support farmers in their system change. Led by Terres Inovia, the project brought together 22 partners for 4 years. It relied on three farmer networks (Berry network, VIVESCIAgrosol club, AGRO D'OC group) to produce three types of tools: (i) dashboards applied to obtaining a robust rapeseed and to the success of sunflower in conservation agriculture, (ii) a decision tree applied to the transition to conservation agriculture, (iii) observation methods to feed these different tools. In this article we also describe the diversity of approaches to advising/supporting farmers and therefore the diversity of expectations in terms of tools and their uses, highlighted during the project. Finally, we propose a framework to help in the construction and use of personalised tools, to contribute to scale up these new approaches of innovation support.La transition agroécologique des exploitations agricoles nécessite de faire évoluer en profondeur les approches de conseil, en plaçant l’agriculteur au centre d’une démarche de co-innovation et de gestion adaptative. Dans ce contexte, l’objectif principal du projet OUTILLAGE était de combler le manque de ressources opérationnelles pour soutenir ces nouvelles approches, en mettant au point des outils d’accompagnement des agriculteurs dans leur changement de système. Piloté par Terres Inovia, le projet a réuni 22 partenaires pendant 4 ans. Il s’est appuyé sur trois réseaux d’agriculteurs (réseau Berry, club VIVESCIAgrosol, groupe AGRO D’OC) pour produire trois types d’outils : (i) des tableaux de bord appliqués à l’obtention d’un colza robuste et à la réussite du tournesol en agriculture de conservation, (ii) un arbre de décision appliqué à la transition vers l’agriculture de conservation, (iii) des méthodes d’observation pour alimenter ces différents outils. Dans cet article, nous décrivons également la diversité des approches de conseil/accompagnement aux agriculteurs et donc la diversité d’attentes en termes d’outils et de leurs usages, mis en évidence au cours du projet. Enfin, nous proposons un cadre pour aider à la construction et l’usage d’outils personnalisés, afin de contribuer au déploiement de ces nouvelles approches d’accompagnement à l’innovatio
Dynamic weighting model of environmental impacts of food systems
No full textInternational audienceDynamic and accurate assessment of environmental impacts of products in relation to national and regional conditions is important for the development of efficient mitigation strategies and policies. Available weighting methods in life cycle assessment rate environmental burdens based on survey- and panel-based approaches. Moreover, the importance of weighted values in relation to current state or environment carrying capacity is not known. It is especially obvious when the weighting is performed for emerging protein products or different regions or performed for the novel protein products like insect or microalgae. Taking the approach of weighting the characterized environmental impacts against the total impacts or impact of specific production chains on a country or regional level allowed to determine their current state importance of environmental influence. Among compared countries, proposed weights based on total national impact, available arable land and country population were the highest for Saudi Arabia and Japan and lowest for China and India. Weights based on impact of protein production supply, arable land and population were more relevant to emerging protein products indicating higher potential impact for Saudi Arabia and Japan. For example, the global Vwarming impact of Acheta domesticus (crickets) as a novel protein source weighted against the impact of total protein supply, available arable lands and population indicated more than 60 times higher eco-potential impacts for India than for Saudi Arabia and Japan, and only 2 times higher than potential impact in the USA, China and Russian Federation. The weights have a dynamic annual resolution and thus represents a sensitive approach for precise disclosure of environmental impact of a product in relation to the current state of environmental influence. They can be used as an-biased explainable weighting factors for the sustainability assessment of products, providing a valuable insight for the research, industry and policymaking
Vitrification of guinea pig (Cavia porcellus) embryos
No full textInternational audienceEstablishment of an embryo cryobank will permit genetic pool preservation of both native breeds and scientifically valuable strains of guinea pig (Cavia porcellus). The aim of the present work was to test a simple vitrification procedure usable directly in field conditions. Female guinea pigs between 6 and 12 months of age weighing from 1.0 to 1.5 kg were housed under farming conditions in an experimental station in La Molina National Agrarian University of Lima (Peru). The protocol of oestrus synchronisation and embryo production was described in our previous studies (Grégoire et al. 2012 Theriogenology 78, 842–847). An ovariohysterectomy was performed 72 h after fertilisation and embryos were flushed from the uterus horn and oviducts with 1 mL lactated Ringer’s solution supplemented with 10% fetal calf serum. Only grade 1 and 2 embryos at 8–16 cells/early morulae stage according to IETS guidelines were selected for cryopreservation and for in vitro control. Embryos (n = 24) were equilibrated for 5 min at room temperature (22–25°C) in a droplet of VS1 solution: VS1 = embryo-holding medium® ([HM], IMV Technologies) + 0.1 M trehalose + 5% ethylene glycol (EG) + 5% dimethyl sulfoxide (DMSO). Then, embryos were transferred to a droplet of VS2 solution (VS2 = HM + 0.2 M trehalose + 10% EG + 10% DMSO) for 3 min, and finally transferred into a VS3 solution (VS3 = HM + 0.4 M trehalose + 20% EG + 20% DMSO) for 30 s. A batch of four embryos was loaded into a 0.25-mL plastic straw using two columns of HM + 0.5 M sucrose separated by air bubbles from the central column (18–20 µL) containing the embryos into VS3. The straws were plunged immediately into liquid nitrogen after VS3 bath. Straws were warmed for 10 s in air at room temperature and 20 s in a 25°C water bath. Immediately after thawing, embryos were expelled and diluted successively 5 min in HM + 0.5 M sucrose, 5 min in HM + 0.25 M sucrose, and 5 min in HM. All the embryos were then in vitro cultured in potassium-enriched simplex optimised medium (EmbryoMax® KSOM Embryo Culture, Millipore) for 48 h at 38.5°C, under 5% CO2 in air and 98% humidity. In vitro survival of embryos was assessed by their ability to develop into hatching or hatched blastocysts after the culture period. A control group of 17 fresh embryos was also in vitro cultured directly after collection in order to test the efficiency of the culture medium. All fresh 8–16 cell embryos developed to the expanded blastocyst stage (17/17) after in vitro culture in KSOM. Regarding the vitrified embryos (8–16 cells to first morulae), all were intact (24/24) after thawing and 2 hours of in vitro culture, and 10/24 (41.7%; 95% Clopper-Pearson confidence interval [22.11;63.36]) reached the expanded blastocyst stage after 48 h of in vitro culture. These results lead us to consider KSOM as an appropriate culture medium for embryo development in guinea pigs. For the first time, vitrified-thawed embryos have been evaluated through a 48 h in vitro culture in Cavia porcellus species
New strategies for the construction and management of pond production systems for sustainable fish farming
No full textInternational audienceFreshwater fish ponds are agro-ecosystems that provide important ecosystem services (ES) to territories, notably by hosting a recognized biodiversity. In France, the low profitability of freshwater ponds for fish production runs the risk that they will be abandoned, and thus that the ES they provide will disappear. The FEAMP SEPURE project brings together scientists from different backgrounds (agronomy, ecology, biology, modelling, environmental sciences) to link farmers' practices, economic and environmental performances and pond responses by monitoring water quality, phytoplankton, zooplankton, benthic macroinvertebrates, aquatic macrophytes and fish communities. Based on the analysis of the contexts and expectations expressed in Dombes, Lorraine and Brenne-Sologne, eleven scenarios with different species assemblages were co-designed with fish farmers. They took into account many parameters, such as the complementarity of species according to their trophic and behavioral traits, water availability, water temperature in summer, the existence of local and national markets, the presence of submerged vegetation, the depth of the ponds, feeding and liming practices, and the use of the ponds for other activities (e.g. hunting). In 10 production sites, farmers applied these scenarios, and practices and ecosystems were monitored. The new data generated by the SEPURE project should help support decision making for the future development of the pond sector and help maintain this economic activity in the territories
Discussion: Prioritize perennial grain development for sustainable food production and environmental benefits
No full textInternational audiencePerennial grains have potential to contribute to ecological intensification of food production by enabling the direct harvest of human-edible crops without requiring annual cycles of disturbance and replanting. Studies of prototype perennial grains and other herbaceous perennials point to the ability of agroecosystems including these crops to protect water quality, enhance wildlife habitat, build soil quality, and sequester soil carbon. However, genetic improvement of perennial grain candidates has been hindered by limited investment due to uncertainty about whether the approach is viable. As efforts to develop perennial grain crops have expanded in past decades, critiques of the approach have arisen. With a recent report of perennial rice producing yields equivalent to those of annual rice over eight consecutive harvests, many theoretical concerns have been alleviated. Some valid questions remain over the timeline for new crop development, but we argue these may be mitigated by implementation of recent technological advances in crop breeding and genetics such as low-cost genotyping, genomic selection, and genome editing. With aggressive research investment in the development of new perennial grain crops, they can be developed and deployed to provide atmospheric greenhouse gas reductions
Development of agroecology in Austria and Germany [version 1; peer review: 2 approved]
No full textInternational audienceBackground: Transforming food systems is necessary to address the global issues of severe biodiversity loss, hunger, and malnutrition as well as the consequences of the rapidly advancing climate change. Agroecology as a systemic approach has been recognised as a promising path of change exemplified in various case studies strengthening this transformation. The aim of this study is to get insight specifically for Austria and Germany in providing an overview of the advancement in agroecology in both countries and identify agroecology-related initiatives. Methods: 21 interviews with experts were conducted to determine the recognition, understanding, and development of agroecology in Austria and Germany in terms of movement, practice, policies, education, and research. In addition, information about agroecology-related initiatives was collected from interviews with 24 representatives of initiatives and literature analysis. Data was analysed according to five activity categories under which agroecology manifest: movement, practice, living lab, science and research infrastructure, and training and education. Results: Results show that the term agroecology is not commonly used in Austria and Germany, where the concept is mainly associated to a scientific discipline. Practices considered agroecological are implemented primarily through organic agriculture, which is very developed in Austria and to a lesser extent in Germany. Many networks, food policy councils, associations, and scientific projects related to agroecology exist, each with specific purposes and ambitions to change farming and food systems. While most selected initiatives do not explicitly refer to agroecology, all follow certain agroecological principles and aim at contributing to accelerate the agroecological transition. Conclusions: Clarifying the concept of agroecology, overcoming economic and political barriers as well as fostering participation of a multitude of stakeholders in the transition is essential for the future development of agroecology in Austria and Germany
Une alimentation sans agriculture demain : la « viande » produite en laboratoire ?
No full textInternational audienceIn order to provide food to a growing population while protecting the planet and the animals, some companies suggest to cultivate muscle cells to produce “meat”. However, this innovation is the subject of three controversies at the intersection of technical, political, legal and societal issues. The first concerns the potential environmental, health and nutritional benefits, which are not widely accepted. The second concerns the ethical and social aspects (artificialization of food and consumer acceptance). Finally, its economic model is still in its infancy due to various strategies and a lack of both hindsight and transparency from the actors.Pour nourrir une population croissante tout en protégeant la planète et les animaux, différentes entreprises proposent de cultiver des cellules musculaires pour produire de la « viande ». Toutefois, cette innovation fait l’objet de plusieurs controverses à l’intersection de problématiques techniques, politiques, légales et sociétales. La première concerne les potentiels bénéfices environnementaux, sanitaires et nutritionnels de cette technologie. La seconde est relative aux aspects éthiques et sociaux (artificialisation de l’alimentation et acceptation par les consommateurs). Enfin, son modèle économique est balbutiant en raison de stratégies variées et d’un manque à la fois de recul et de transparence de la part des acteurs
Pathways and schemes for Agroecology Territories across Europe
No full textInternational audienceCurrent literature emphasizes the importance of territorial level and place-based approaches at landscape scale, involving local communities to foster transition to agroecology and sustainable food systems. Related to this, the concept of Agroecology-Territories (AET) has been proposed and is based on territorial action on three dimensions (i) the adaptation of agricultural practices, (ii) the conservation of biodiversity and natural resources, and (iii) the development of embedded food systems. This paper analyses the current development of AET or similar concepts in Europe and questions the relevance of this concept as an upscaling pathway for agroecology, considering economic, environmental and social aspects. Driven through the European AE4EU project, this research is based on a literature review, 26 semi-structured interviews with informants from Spain, UK, Italy, France and Germany. The analysis highlights the gradual emergence of different territorial schemes across Europe that support transitions to sustainable food systems, with three main roots in rural development, territorial food systems, and agri-environment and biodiversity conservation. The current use of the AET concept in the literature seems to be sometimes spatially limited to a specific scientific community whereas an important body of literature was found on comparable territorial schemes or promoting the relevance of territorial approaches. Among the 11 schemes compared, three have been identified as having a good potential toward qualifying as an AET as they covered the three dimensions and involve stakeholders: Bio-districts (Italy), Eco-model regions (Germany), and Regional Nature Parks (France). The comparison of those schemes through eight case studies provides interesting insights regarding the conditions, levers and barriers for sustainable transition pathways at territorial level. The AET concept appears throughout this work as a fertile and promising frame to design and extend current existing territorial schemes and their area of action to promote the development of agroecology