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Perspectives concernant l'impact de l'initiative « 3 degrés de plus » sur la durée de conservation des aliments surgelés
No full textInternational audienceFrozen storage temperature plays a crucial role in preserving the initial quality of frozen foods. The most used storage temperature of frozen food is -18°C and is based on 0°F, which corresponds to -17.8°C. This temperature does not correlate with a specific ratio of frozen water in foods (“level of frozenness”-LOF) and has been arbitrarily chosen. The fact is that at -18°C, most foods never reach 100% LOF (usually in the range of 95% LOF). The 100% LOF refers to a state in which the maximum ice crystallization zone has been covered (usually around -30°C). New lowtemperature storage modes, such as chilling, superchilling, and supercooling, gained attention in academia and in the food industry, pushing the boundaries of existing regulations. The recent “Three Degrees if Change” initiative launched by the University of Birmingham (UK) aims at exploring the interest and impact of changing the frozenfood storage temperature from -18°C to -15°C. This paper proposes a review of the current regulations in connection with selected subzero temperature storages. Based on the principle of the Q10 models (Ratio of a food quality loss rate at T+10°C divided by said rate at T°C), a Q3 model is proposed showing that frozen foods stored at -15°C may lose around 30% of their quality life from the sensorial point of view. Raising the temperature to -15°C should not pose a major microbial risk; however, this point must be under scrutiny. In particular, the permitted temperature oscillations during transport and at the retail outlet may require some adjustment.La température de stockage en congélation joue un rôle crucial dans la préservation de la qualité initiale des aliments surgelés. La température de conservation la plus utilisée est de -18 °C, équivalente à 0 °F (soit -17,8 °C). Cette température a été choisie arbitrairement, sans correspondre à un certain pourcentage d’eau congelée dans les aliments (appelé « niveau de congélation » – LOF). En réalité, à -18°C, la plupart des aliments n’atteignent jamais un LOF de 100 % (généralement autour de 95 %). Le LOF de 100 % correspond à un état où la zone maximale de cristallisation de la glace a été atteinte (généralement vers -30 °C).L’initiative récente « Trois Degrés de Plus », lancée par l’Université de Birmingham (Royaume-Uni) en 2023 en collaboration avec l’IIF, vise à faire évoluer la température de stockage des aliments surgelés de -18 °C à -15 °C. Cet article propose des perspectives sur l’effet d’une telle mesure sur la qualité des produits surgelés. En se basant sur le principe des modèles Q10 (rapport d’une vitesse de perte de qualité d’un aliment à T+10 °C divisée par ladite vitesse à T °C, aussi appelé coefficient de température ou sensibilité), un modèle Q3 est proposé, montrant que les aliments surgelés stockés à -15 °C peuvent perdre environ 30 % de leur durée de vie en termes de qualité sensorielle. Une élévation de la température à -15 °C ne devrait pas poser de risque microbien ni de risque sur les virus ; néanmoins, ce point doit être surveillé de près. En particulier, les oscillations de température actuellement tolérées durant le transport et dans les points de vente pourraient nécessiter des ajustements
Alternatives to polarity reversal to cope with mineral cathodic electro-precipitation: A critical review on reactor engineering factors in limiting scaling issues or favoring valuable compounds recovery
No full textInternational audienceMineral scaling deposition can occur naturally (in the presence of Ca2+, Mg2+, phosphates, carbonates, etc.) while treating water, and it is an evergreen problem. Technical and economic issues pertaining to calcareous scaling in industrial plants and domestic equipment have triggered research on this topic for several decades, including via electrochemical methods. Polarity reversal has been known to be one of the most feasible techniques to mitigate mineral scaling. Nevertheless, its application is not omnipotent in all cases and conditions, while only efficient in several specific conditions. In the last couple of years, owing to technological advancements and catapulted engineering knowledge, alternatives to polarity reversal have been proposed by modifying reactor design, cathode material, and maneuvering the electrochemical operating conditions. This exploration has since widened the application range of electrolysis. Electro-precipitation that was previously seen as fiendish has only recently been considered a virtue when it can recover value-added compounds from aqueous effluents.Henceforth, this critical review will credit the application of polarity reversal wherever implementable. But more emphasis will be given to its alternative to minimize the occurrence of mineral scaling. This review will also debug the technical and engineering aspects of electrochemical reactors, in which scaling/electro-precipitation is purposefully promoted. This second part of the review will then address the recovery of precious compounds/elements from wastes in line with the international goal of circular economic implementation
Effect of Printing Temperature on the Microstructure and Tensile Properties of Polylactic Acid–Magnetic Iron Composites Manufactured by Material Extrusion
No full textInternational audienceIn this study, we examined how printing temperature affects the microstructure and mechanical properties of polylactic acid (PLA) composite reinforced with iron oxide i.e., magnetite manufactured using a material extrusion technique. The composite was printed at temperatures from 185 • C to 215 • C. Microstructure analysis via synchrotron radiation Xray microtomography revealed changes in both iron oxide and porosity contents within the printed structures. Mechanical testing results demonstrated a limited effect of the printing temperature on tensile performance. Finite element computation is considered to predict the elasticity behavior of the printed composite by converting 3D images into 3D structural meshes. When implementing a two-phase model, the predictions show a leading role of the iron oxide content, and an overestimation of the stiffness of the composite. A three-phase model demonstrates a better matching of the experimental results suggesting a limited load transfer across the PLA-iron oxide interface with Young's moduli in the interphase zone as small as 10% of PLA Young's modulus. Magnetic actuation demonstrates that experiments on PLA-iron oxide plates reveal a pronounced thickness-dependent limitation, with the maximum deflection observed in thin strips of 0.4 mm
Optimization of biomolecule extraction from Spirulina platensis with [bmim][Cl]
No full textInternational audienceSpirulina platensis stands out as a promising raw material for various industries due to its composition, rich in proteins and carbohydrates, and its valuable phycobiliprotein content. This study explored the influence of four key factors – incubation time, incubation temperature, ultrasound exposure, and IL mass fraction – on the single-step extraction of these cyanobacterial ingredients using [bmim][Cl]. Results were analysed through a four-factor surface response analysis, allowing the identification of the most relevant operational factors for the extraction of each biomolecule.The IL mass fraction in its linear and quadratic form emerged as the primary factor influencing protein and phycobiliprotein recoveries, although other factors such as the interaction between incubation time and incubation temperature were also deemed significant. In these experiments, protein recovery ranged over a wide yet low range, going from 2.37 to 24.30 %, while phycobiliprotein recovery did not reach 10 % for any of the three studied pigments. In contrast, carbohydrate recovery was higher. It ranged between 35.85 and 63.25 %, and was only influenced by the linear term for the incubation temperature.The excellent fit of the protein recovery model and its pronounced ascending trend with increasing IL mass fractions prompted further experimental work into the influence of this factor. These additional experiments, focusing solely on the IL mass fraction, confirmed the observations derived from the surface response analysis, with IL mass fractions outside the studied range following the observed ascending trend. Such post-model experiments led to higher recoveries even when operating at low IL mass fractions due to the suppression of negatively-influencing factors, leading to single-step protein recoveries ranging between 15.92 and 28.95 %.The purity of the obtained extracts from both model and post-model experiment was also evaluated. Purity in model experiments was driven by practically the same factors influencing biomolecule recovery, while post-model experiments revealed how the change of the operational conditions not only increased protein recovery, but also boosted its purity
Heavy Metal Contamination in Yogurt from Lebanon: Evaluating Lead (Pb) and Cadmium (Cd) Concentrations Across Multiple Regions
No full textInternational audienceThe toxicity of metals such as lead (Pb) and cadmium (Cd) makes heavy metal contamination in food products a major health concern. The aim of this study is to measure the levels of Pb and Cd in yogurt samples that were collected from 11 distinct Lebanese locations and determine their compliance with the legal limits set by the European Commission (0.02 mg/kg for Pb and 0.005 mg/kg for Cd). A total of 165 yogurt samples were examined using atomic absorption spectrophotometry (AAS). Interestingly, the findings showed that 10.9% of samples had Pb concentrations over the allowable limit; the highest amounts were observed in Baalbeck-Hermel (0.118 mg/kg), North Area (0.125 mg/kg), and South Lebanon (0.115 mg/kg). In addition, the highest detected concentrations of Cd were found in North Area (0.094 mg/kg), Baalbeck-Hermel (0.076 mg/kg), and Akkar (0.042 mg/kg), with 14.5% of samples above the limit. The results show regional differences in contamination, which are probably caused by industrial emissions, agricultural activities, and environmental pollution. To better understand the potential health implications, the estimated daily intake (EDI) of Pb and Cd through yogurt consumption was calculated and compared to international healthbased guidance values. Although the EDI values suggest a low risk from yogurt alone, the findings highlight the importance of cumulative exposure and emphasize the necessity of regular monitoring and stricter implementation of food safety laws to decrease exposure to heavy metals through dairy intake.</div
Thermal and Expansion Analysis of the Lebanese Flatbread Baking Process Using a High-Temperature Tunnel Oven
No full textInternational audienceThis study investigates the thermal dynamics and material behavior involved in the baking process for Lebanese flatbread, focusing on the heat transfer mechanisms, water loss, and dough expansion under high-temperature conditions. Despite previous studies on flatbread baking using impingement or conventional ovens, this work presents the first experimental investigation of the traditional Lebanese flatbread baking process under realistic industrial conditions, specifically using a high-temperature tunnel oven with direct flame heating, extremely short baking times (~10–12 s), and peak temperatures reaching ~650 °C, which are essential to achieving the characteristic pocket formation and texture of Lebanese bread. This experimental study characterizes the baking kinetics of traditional Lebanese flatbread, recording mass loss pre- and post-baking, thermal profiles, and dough expansion through real-time temperature measurements and video recordings, providing insights into the dough’s thermal response and expansion behavior under high-temperature conditions. A custom-designed instrumented oven with a steel conveyor and a direct flame burner was employed. The dough, prepared following a traditional recipe, was analyzed during the baking process using K-type thermocouples and visual monitoring. Results revealed that Lebanese bread undergoes significant water loss due to high baking temperatures (~650 °C), leading to rapid crust formation and pocket development. Empirical equations modeling the relationship between baking time, temperature, and expansion were developed with high predictive accuracy. Additionally, an energy analysis revealed that the total energy required to bake Lebanese bread is approximately 667 kJ/kg, with an overall thermal efficiency of only 21%, dropping to 16% when preheating is included. According to previous CFD (Computational Fluid Dynamics) simulations, most heat loss in similar tunnel ovens occurs via the chimney (50%) and oven walls (29%). These findings contribute to understanding the broader thermophysical principles that can be applied to the development of more efficient baking processes for various types of bread. The empirical models developed in this study can be applied to automating and refining the industrial production of Lebanese flatbread, ensuring consistent product quality across different baking environments. Future studies will extend this work to alternative oven designs and dough formulations
Wheat flour dry heat treatment (DHT): effect of time-temperature parameters on wheat flour functionalities in the case of sponge cake applications
No full textInternational audienceThe application of a Dry Heat Treatment (DHT) on wheat flour is of interest regarding the clean label high ratio cakes production as it helps to maintain the cake structure without altering the final volume. This study aims at further exploring the DHT impact on the flour's functionalities such as the starch gelatinization enthalpy and the pasting properties using the Chopin technologies-MIXOLAB 2 equipment. This study also relates to the batter and cake properties including the batter viscosity and the cake volume and shape. The application of a DHT process at different time and temperature combinations – ranging from 108 to 151 °C and from 10 to 40 min – led to modifications on the protein quality and starch characteristics of the wheat flour. The batters made with DHT flours had higher viscosities than the control batter. Furthermore, the sponge cakes made with standard flour (control) and flours treated at 108 °C-25 min had similar specific volumes. However, the cake structure collapsed when the cake was made with the standard flour, as it did not when the cake was made of the heat treated flour. The enhancement of starch's gelatinization is suggested to be the main effect to take place during the DHT process leading to a higher viscosity, which may eventually alter the cake specific volume. The heat treated flour has shown enhanced functionalities that are suitable for a clean label high ratio sponge cake. Their application in different food matrices is still yet to be investigated
Actualisation des connaissances sur le complexe gingivo-stomatite chronique félin et données cliniques sur la thérapie via les cellules souches mésenchymateuses
No full textLa gingivo-stomatite chronique féline est une affection inflammatoire sévère, multifactorielle et douloureuse de la cavité buccale du chat. Elle touche jusqu’à 26 % des individus et altère considérablement leur qualité de vie. Ce travail propose une actualisation des connaissances sur la physiopathologie, les facteurs étiologiques (dont le rôle clé du Calicivirus félin), et les déséquilibres immunitaires et microbiens observés chez les animaux atteints. L’étude détaille également les signes cliniques, les critères diagnostiques, ainsi que les traitements conventionnels. Si l’extraction dentaire reste la thérapeutique de référence, certains cas réfractaires nécessitent des alternatives. Une attention particulière est portée à l’usage innovant des cellules souches mésenchymateuses. Après un rappel de leurs propriétés immunomodulatrices, les données internationales et françaises existantes sont analysées. Une étude pilote française, incluant plusieurs chats traités par thérapie cellulaire, est présentée : les résultats montrent des améliorations cliniques encourageantes. Cette approche cellulaire, encore en développement, pourrait représenter une option thérapeutique prometteuse pour les cas les plus sévères. Cette thèse vise ainsi à fournir aux praticiens une synthèse actualisée des connaissances et des pistes concrètes de prise en charge de cette pathologie complexe
Impaired organic and mineral extracellular matrix composition in early-onset osteoporosis
No full textInternational audienceBackground Early-onset osteoporosis (EOOP) is a rare form of primary osteoporosis defined by major skeletal fractures or low bone mineral density (BMD) that occurs in early age. However, the characteristics of the extracellular matrix that may contribute to bone fragility are unknown. Purpose We explored the microarchitecture and bone matrix composition in transiliac bone biopsies (BBs) obtained from adults with EOOP. Methods We compared EOOP BBs to historical control BBs. Microarchitecture was measured by μ-CT and bone matrix composition by Raman microspectroscopy and FTIR spectroscopy. Mechanical response of the bone matrix was investigated by nanoindentation. The contribution of each parameter was assessed by principal component analysis (PCA). Results We compared 18 BBs for EOOP patients (mean [SD] age 34 [8] years, lumbar-spine BMD Z-score -2.05 [1.04]) to 19 BBs for age-matched healthy individuals. Patients had vertebral fractures only (n=7), peripheral fracture only (n=6) and both vertebral and peripheral fractures (n=3). EOOP and controls had similar bone volume (bone volume/total volume, p=0.741). As compared with controls, EOOP BBs showed lower trabecular separation (p=0.026) and higher trabecular connectivity density (p<0.001); cortical thickness was lower in EOOP BBs (p<0.01). Also, GAG/Amide III and hydroxyproline/proline ratios as well as accumulation of AGEs were greater in EOOP than controls (all p<0.0001). Moreover, tissue mineralization was lower in EOOP than controls, as shown by v1PO4/CH2 ratio, mineral maturity crystallinity and crystal size index (all p<0.005). Hardness, indentation modulus and maximum load were all altered in EOOP. PCA revealed greater contribution of both the organic and mineral matrix phase at the trabecular and cortical EOOP bone rather than bone microarchitecture. Conclusion The matrix composition of bone showed greater damage of the organic matrix phase and reduced mineralization in EOOP patients than controls, which may explain the high risk of fracture in EOOP patients and may differentiate EOOP from other bone diseases
Evaluation d'un outil d'aide à la décision, du point de vue de l'éleveur, pour la maîtrise des troubles respiratoirs en atelier d'engraissement de jeunes bovins
No full textInfectious bovine bronchopneumonia (IBR) is the leading pathology encountered in young bull fattening units. Its economic impact is considerable, and to date, no decision support tool is available to farmers that enables early detection and effective management of this disease. In the context of the development of precision livestock farming, the decision support tool SEPTIME was developed to address this issue. The aim of this study was to evaluate to what extent the SEPTIME tool meets farmers' expectations in managing IBR through data valorization and the use of new technologies. Qualitative surveys in the form of semi-structured interviews were conducted with eight farmers who had previously tested the tool. Thematic analysis of the survey results reveals that the tool is perceived as having strong potential for improving IBR management, provided that certain improvements are made. While it contributes to farmer well-being, its impact on economic outcomes and antibiotic use remains unclear. Although it shows significant potential for managing IBR in fattening systems, the tool does not reduce risk factors, and it highlights some limitations of decision support tools for detecting health disorders.Les bronchopneumonies infectieuses (BPI) représentent la principale pathologie rencontrée en atelier d’engraissement de jeunes bovins. Ses répercussions économiques sont importantes, et il n’existe à ce jour aucun outil d’aide à la décision disponible pour les éleveurs permettant une détection précoce et une gestion efficace de cette pathologie. Dans un contexte de développement de l’élevage de précision, l’outil d’aide à la décision SEPTIME a été développé dans le but de répondre à cette problématique. Cette étude avait pour but d’évaluer dans quelle mesure l’outil SEPTIME répondait aux attentes des éleveurs en matière de gestion des BPI via la valorisation des données et l’utilisation des nouvelles technologies. Des enquêtes qualitatives sous la forme d’entretiens semi-directifs ont été réalisées auprès de 8 éleveurs ayant préalablement testé l’outil. L’analyse thématique des résultats des enquêtes révèle que l’outil est perçu comme présentant un fort potentiel pour l'amélioration de la gestion des BPI, à condition d’y apporter certaines améliorations. Il contribue au bien-être de l’éleveur, mais son impact sur les ressources économiques et l’utilisation d’antibiotiques n’est pas évident. Bien qu’il présente un potentiel important pour la gestion des BPI en élevage, l’outil ne réduit pas les facteurs de risque et illustre des limites de l’utilisation d’un OAD pour la détection des troubles de santé