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The gas (O2 and CO2) permeability of an innovative stratified PE–organoclay (LLDPE/OMMT) nano-enabled composite films was studied for the first time and related to the self-assembly process driven by hydrophobic interactions. An 84.4% and a 70% reduction (i.e. a barrier improvement factor of about 6, sufficient for food packaging applications) were observed respectively in the oxygen and carbon dioxide permeability of the 5 bilayers coated film compared to the substrate, while only incorporating 2.4 v/v% of organoclay in the composite and increasing the thickness by 17.7%. Such drastic effect with so low amount of organoclays cannot be achieved by conventional melt blending/exfoliation of the clays into the polymer matrix and is due to a geometrical blocking effect of a brick-wall and compact layer structure of the impermeable clay tactoids. Mathematical prediction of oxygen barrier performance of PE/OMMT films has revealed that 12 bilayers would be necessary to further achieve a barrier improvement factor of 10.

International audience; Despite CO2 production and diffusion during ripening of semi-hard Swiss-type cheese are considered as important quality parameters, the research concerning key gas production and transfer in cheese remains widely overlooked. In this study, experimentally assessed CO2 production was coupled with transfer coefficients in a mathematical model in order to predict CO2 gradients formed inside the cheese during ripening. The permeability coefficient of CO2 through the multilayer barrier packaging which wraps the cheese during ripening was also included in the model. The presented model was validated by assessing the CO2 concentration in the cheese and its partial pressure in the packaging headspace. CO2 production rate was found to be the most important input parameter affecting CO2 gradients formed in cheese during ripening whereas the other input parameters (solubility, diffusivity, permeability) had little effect on the total CO2 gradient.

Modified atmosphere packaging (MAP) is commonly used for packing fruits and relies on the natural interplay between the produce physiology (consumption or production of gases and vapours) and the mass transfer properties of the packaging material (gases and vapours permeation values), with possible gas flushing, in order to reach optimal conditions of storage. Then success of MAP depends on the choice of the material, whose mass transfer properties must match produce requirements. Decision aid tool for MAP of fruits would aim at helping decision makers to find the best material for a given fruit, but are not yet well developed and commonly used. If virtual MAP models exist, their objective is to dimension gas permeabilities of the packaging material to the needs of the fruit. They do not take into account multi-criteria design such as cost and mechanical properties. Then, this chapter brings an overview on current researches and developments in the field of biological, material, and computing science that could lead to the development of such a tool in regard to constitution of databases, and reliability of optimization and interrogation procedures.

A mathematical model describing the water content-dependent release of an antimicrobial agent (allyl isothiocyanate (AITC)) from a bio-based film to the packaging headspace was implemented. The system was characterised experimentally by assessing release kinetics and diffusivities. The model was validated by comparing simulations to experimental data. In spite of the high complexity of the system coupling moisture and antimicrobial diffusion within the packaging material and then release into headspace, the presented model provides a good enough reproduction of experimental conditions. A sensitivity study conducted on the model showed that the release kinetics of the antimicrobial agent were the most influential parameters, and that the diffusivity of moisture and AITC within the film have negligible impact. The model was then used to demonstrate the efficiency of such packaging for shelf-life optimization as it successfully inhibited the growth of bacteria. This work provides a framework that can be used for decision support systems. Industrial relevance This work is relevant to industrial considerations as it provides a framework for decision support systems to help manufacturers and researchers to tailor their active packaging. Indeed, the development of anti-microbial applications for food packaging is a time-consuming task, that, if undertaken from a sole experimental point of view, can also be expensive. The use of the simulation framework proposed (that was experimentally validated) helps investigate and compare multiple packaging configurations. Numerical simulation are made by changing the kinetics of release parameters and initial anti-microbial content within the packaging without requiring further experiments, the main issue lying on having plausible values for the parameters.

RFID (Radio Frequency Identification) technology has considerably grown in the past few years and is nowadays sought to be implemented for the identification of products and for traceability in the agrifood sector, ensuring food safety and quality. RFID is now considered as the worthy successor of the barcode with a foreseen expansion not only in the agrifood sector, but also in industrial sectors for environmental monitoring (temperature, relative humidity and luminosity) through namely WSN (Wireless Sensor Network) and WST (Wireless Sensor Technology). Research studies are being progressively performed in the objective of coupling sensors to the RFID technology. This interfacing would lead to a better monitoring of packaging headspace by means of the development of different sensors, as well as their coupling to RFID tags through the microchip or directly to the RFID antenna. The present work gives an overview of the basics of the RFID technology, the existing sensors and the ones being developed to be interfaced with the technology, as well as the existing RFID sensor tags. The presented literature studies, mainly in the agrifood sector, demonstrate how RFID may meet our needs for a better monitoring of food quality by coupling radio frequency communication and traceability. The implementation of sensors which is a very new technology being studied and concomitantly developed may lead to a better detection of food degradation markers and thus to a reduction in food loss which is one of the world's major issue.

Berry-based products that have beneficial effects on consumer health are competitive on themarket only if consumers understand the benefits of such products. The purpose of this research was togain in-depth analysis the factors that influence the consumer choices and behaviour towards berrybased food products in three different countries, from eastern and western Europe: Romania, Franceand Turkey. These three countries as a three distinctive markets for organic products were chosen tofind out similar and different attitudes and behaviour towards organic food consumption. This crossculturalconsumer study aims to contribute to socio-economic research market actors and policymakers. French consumers appear to be the most loyal consumers of berries-based products out of thethree countries investigated, preferring mostly fresh berries, jams and dairy products based on berries.In Turkey and Romania, the berries consumption is mostly occasional. Turkish consumers prefer mainlydried berries, while Romanian consumers – the frozen variant and muesli.

The use of wheat gluten as sensing material to detect carbon dioxide is a promising approach. The dielectric properties of wheat gluten are modified in contact with carbon dioxide gas at high relative humidity (90%) and at a temperature of 25 °C due to a structural change in the sensing material, where amino groups act as receptors to carbon dioxide molecules. In the present study, the effects of carbon dioxide on the electrical and dielectric properties of wheat gluten at 20% and 90% of relative humidity (usually found in food packaging) are determined and discussed. At 90% of relative humidity, a linear increase of the dielectric permittivity and dielectric loss was observed with a significant hysteresis which increased with the number of carbon dioxide treatment cycles. One of the significant results is the increase in the dielectric permittivity from 7.01 ± 0.07 to 12.02 ± 0.03 with a sensitivity of 31.38 ± 0.06 fF/%CO2 measured at 868 MHz. The developed sensor is sought to be integrated in the design of UHF-RFID (ultra-high frequency − radio frequency identification) systems working at 868 MHz.

International audience; This study focuses on CO2 diffusivity, which is one of the most important factors impacting eye growth in semi-hard cheese, but yet has scarcely been investigated in literature. The effect of compositional and ripening parameters on experimental CO2 diffusivity in semi-hard cheese was studied. CO2 diffusivity in semi-hard cheese showed a complex relationship with temperature in the range 4 to 25 °C, represented by a quadratic curve with the highest diffusivity at 13 °C. Salt was found to impact CO2 diffusivity, with a decrease of about 60% for 0 to 2.7% w/w salt addition, which may be ascribed to viscosity increase of the cheese matrix and “salting in” effect of protein. CO2 diffusivity was found to increase with moisture content from 39 to 42% w/w, then it decreased from 42 to 48% w/w. Inevitable changes in protein content of the three cheese variants may be responsible for the complex behaviour observed.

Despite the fact that CO2 production by Propionic Acid Bacteria (PAB) fermentation is the driving force for eye growth in most hard and semi-hard cheese types, few coefficients of CO2 production have been assessed in literature. In this study, the diffusion free CO2 production rate coefficient was experimentally assessed in semi-hard cheese as a function of salt content (0-1.3% w/w), ripening temperature (13-25 degrees C) and ripening time (2 weeks). The CO2 production rate decreased linearly with increasing salt content due to the inhibition effects of salt on the PAB, while it increased with temperature, due to the vicinity with the Poptimum growth temperature (25-30 degrees C). A lower rate of production was observed in the first days of ripening, followed by an increase in CO2 production rate and consequent decrease due to the lower availability of the main substrate (lactate). We proposed a polynomial equation for predicting changes in the CO2 production rate during ripening. This equation may be used to better describe the phenomenon of eye growth occurring in cheese with propionic acid fermentation.

Assessing gas permeation of the whole food packaging in industrial conditions (RH, temperature including stretching and sealing effect) is fundamental for predicting the quality changes of packed food during processing and shelf life. Permeability coefficients are usually assessed on a small flat, piece of packaging material which is not representative of the whole pack (usually assembly of tray + lid film or pouches of flexible films sealed on at least 2 or 3 sides) used in the industry. Moreover, conditions used are standardised (temperature of 23 °C, 0%RH) which are not representative of conditions that prevail in real use. This simplified approach may lead to erroneous mass transfer predictions when simplified permeability values are used in calculation. To face this problem, we propose a simple methodology for the assessment of the gas permeability coefficients (N2, CO2, O2) in sealed intact large scale (industrial) packaging (whole packaging) in conditions of temp and RH mimicking the real conditions of use (encountered by the material in contact with the food product). The CO2 permeability assessed in the industrial-like conditions was significantly higher compared to the one assessed with standard method. The higher gas permeation measured was ascribed to the impact of industrial operations such as shrinking and hot sealing. Our results highlight the necessity to better characterize impacts of industrial conditions such as hot sealing and shrinking on the permeability of the whole pack when prediction of gas permeation through packaging during food processing is needed.

Despite CO2 being one of the most important gases affecting the quality of most semi-hard cheeses, the thermodynamic properties of this molecule in relation to cheese ripening have rarely been investigated. In this study the CO2 solubility coefficient was experimentally assessed in semi-hard cheese as a function of the most relevant compositional and ripening variables. As expected, CO2 solubility was found to linearly decrease with temperature in the range 2–25 °C. Unexpectedly, solubility was not significantly different at 39% and 48% moisture, while it was found lower at 42%. Unavoidable changes in protein content of the three cheese variants is suspected to produce an interaction with water content, leading to complex interpretation of the results. Increasing salt content in cheese from 0 to 2.7% w/w significantly decreased CO2 solubility by about 25%, probably due to the increased bonded water molecules in the cheese water phase.

182A wide range of film-forming compounds are available today and facilitate the design and tailoring of edible films and coatings with optimized functional properties. The main targeted functional properties are mass transfer properties, that is, solubility, diffusivity, and permeability compatible with the targeted applications, for example, moisture or O2 barrier, controlled release of an active agent, O2 scavenging property, among others. The dimensioning of an edible film or coating relies thus essentially on the knowledge of its targeted mass transfer property. Despite recent huge efforts made in the development of integrated approach for building the specifications of edible film and coating, a realistic assessment of the film or coating efficacy is still critical. Mathematical modeling of mass transfer phenomena involved in the coated food is the base of a better realistic assessment of the performance of protective edible films. The aim of this chapter is to make a progress report on the measurement of mass transfer properties and on the modeling of mass transfer into the coating/food system. The last section illustrates how mathematical tools could be used to adequately dimension edible films or coatings.

This study reports the first effort to synthesize a new type of PE–organoclay multilayer film by starting from an uncharged apolar polymer substrate and successively depositing apolar organoclay and uncharged apolar polyethylene (PE) layers with subsequent repeating depositions. The alternate variation of contact angle (85° average for organoclay and 107° for PE layers) confirmed the profilometry and the scanning electron microscopy results as well as the linear growth pattern, i.e. the successful highly stratified assembly of repetitive bilayers comprised of 450 nm organoclays and 2.25 μm PE layers. The self-assembly of organoclays on PE surfaces was driven by solvophobic molecular construction involving hydrophobic interactions between the organic parts of the organoclay tactoids dispersed in an organic solvent and the PE hydrophobic surface. The deposition of PE molecules on the organoclay layers was the result of a dip-coating process involving physical sorption of a highly viscous PE solution on the surface of the organoclay layers.

An interdigital capacitor (IDC) system was designed in order to provide a controlled high exposure (high surface/thickness ratio) to the environmental atmosphere of a sensing layer of which the dielectric properties were identified by a finite element method simulation and validated using a common parallel plate capacitor technique. The dielectric properties of one of the most sensitive and widely available plant polymers in nature: wheat gluten (WG) proteins were determined at ultra high frequency (500 MHz-1000 MHz) at 25 degrees C and at two different values of relative humidity (RH). Increasing relative humidity from 20% RH to 80% RH increased the dielectric loss and permittivity of wheat gluten from 0.39 +/- 0.01 to 0.84 +/- 0.02 and from 5.01 +/- 0.06 to 7.07 +/- 0.18, respectively. This effect was discussed in the light of wheat gluten composition (constituting amino acids), structure (high molecular weight, proteins unfolding and mobility) and water content (adsorbed water-bonding state). In addition to RH, two other analytes known as food quality markers, carbon dioxide (CO2) and ethanol were studied in terms of sensitivity. The sensitivities of 10.0 +/- 0.4 fF/%RH, 31.38 +/- 0.06 fF/%CO2 and 25.50 +/- 0.05 pF/%ethanol obtained should pave the way for the development of innovative green radio frequency identification (RFID) tags using renewable, cheap and biodegradable plant polymers as gas and vapor sensors. The sensors are intended to be interfaced to low-cost, ultra high frequency, passive, RFID tags for monitoring food quality and freshness volatile markers in packaging headspace.

Based on the measurement of local oxygen partial pressure kinetic, a non-invasive methodology was proposed to assess O2 diffusivity ( D O 2 ) in liquid, viscous and solid matrices. This new method was compared with a previous invasive method, developed by the same group, based on the same principle. The new method has proven to be essential to measure D O 2 in solid food matrices where invasive methods usually failed. It was successfully used to obtain D O 2 of cooked ham and processed cheese which were found respectively equal to 0.450 ± 0.004 × 10−9 m2·s−1 and 1.15 ± 0.11 × 10−9 m2·s−1 at 20 °C. D O 2 was also evaluated as a function of temperature (from 5 to 30 °C) and viscosity in lipid-based matrices. These results have permitted to determine activation energy of the diffusion and have revealed that increasing viscosity of the lipid matrices tested did not impact their D O 2 values.

We define a multi-criteria Decision Support System for designing fresh food packaging.An argumentation module gathering stakeholders' preferences is included in the DSS.The argumentation module computes the consensual stakeholders' preferences.Using the DSS the user will have only one trial to perform validation step. Within the framework of the European project EcoBioCap (ECOefficient BIOdegradable Composite Advanced Packaging), aiming at conceiving the next generation of food packagings, we have designed an argumentation-based tool for management of conflicting viewpoints between preferences expressed by the involved parties (food and packaging industries, health authorities, consumers, waste management authority, etc.). The requirements and user preferences are modeled by several rules provided by the stakeholders expressing their viewpoints and expertise. Based on these rules, the argumentation tool computes consensual preferences which are used to parameterize a flexible querying process of a packaging database to retrieve the most relevant solution to pack a given food. In this paper, we recall briefly the principles underlying the reasoning process, and we detail the main functionalities and the architecture of the argumentation tool. We cover the overall reasoning steps starting from formal representation of text arguments and ending by extraction of justified preferences which are sent to the database querying process. Finally, we detail its operational functioning through a real life case study to determine the justifiable choices between recyclable, compostable and biodegradable packaging materials based on stakeholders' arguments.

We define a multi-criteria Decision Support System for designing fresh food packaging.A modified atmosphere packaging simulation module is included in the DSS.A flexible querying module handles imprecise data stored in a packaging database.Using the DSS the user will have only one trial to perform validation step. To design new packaging for fresh food, stakeholders of the food chain express their needs and requirements, according to some goals and objectives. These requirements can be gathered into two groups: (i) fresh food related characteristics and (ii) packaging intrinsic characteristics. Modified Atmosphere Packaging (MAP) is an efficient way to delay senescence and spoilage and thus to extend the very short shelf life of respiring products such as fresh fruits and vegetables. Consequently, packaging O2/CO2 permeabilities must fit the requirements of fresh fruits and vegetable as predicted by virtual MAP simulating tools. Beyond gas permeabilities, the choice of a packaging material for fresh produce includes numerous other factors such as the cost, availability, potential contaminants of raw materials, process ability, and waste management constraints. For instance, the user may have the following multi-criteria query for his/her product asking for a packaging with optimal gas permeabilities that guarantee product quality and optionally a transparent packaging material made from renewable resources with a cost for raw material less than 3?/kg. To help stakeholders taking a rational decision based on the expressed needs, a new multi-criteria Decision Support System (DSS) for designing biodegradable packaging for fresh produce has been built. In this paper we present the functional specification, the software architecture and the implementation of the developed tool. This tool includes (i) a MAP simulation module combining mass transfer models and respiration of the food, (ii) a multi-criteria flexible querying module which handles imprecise, uncertain and missing data stored in the database. We detail its operational functioning through a real life case study to determine the most satisfactory materials for apricots packaging.

CO2 is produced by many microorganisms present in cheese and it can affect cheese quality both during processing and storage. The knowledge of the extent of CO2 production by cheese microorganism (CO2 production rate coefficients) may be used to predict gas exchange in cheese/packaging systems, helping dairy industries in the right choice of the packaging (higher/lower gas permeability) and mastering of cheese ripening. However very few coefficients for CO2 production rate have been published and the ones assessed in vitro (not inside real food) may not well describe the activity of the microorganisms in situ. We have therefore developed a methodology for the in situ assessment of CO2 production rate and applied it to cheese with propionic acid fermentation. The proposed methodology is based on infra-red measurement of CO2 and it allows measuring its accumulation up to 1% with 0.001% resolution, while monitoring the level of oxygen. The method showed a good repeatability, with a low coefficient of variation within samples (6.6%) and between samples (8.4%) compared to 10–30% between samples found in literature. The method was compared with a gas chromatography based method, which is also described.

International audience; Within the framework of the European project EcoBioCap (ECOefficient BIOdegradable Composite Advanced Packaging), we model a real world use case aiming at conceiving the next generation of food packagings. The objective is to select packaging materials according to possibly conflicting requirements expressed by the involved parties (food and packaging industries, health authorities, consumers, waste management authority, etc.). The requirements and user preferences are modeled by several ontological rules provided by the stakeholders expressing their viewpoints and expertise. To deal with these several aspects (CO 2 and O 2 permeance, interaction with the product, sanitary, cost, end of life, etc.) for packaging selection, an argumentation process has been introduced.

Composite materials made from fibrous support coated with agro-polymers are widely commercialized for different appli- cations. But, their transfer properties have only been sparingly studied despite their importance in membrane technologies or food packaging. Furthermore, most of past studies on the topic have been focused on the impact of surface properties of the support on the final coated material structure and its properties; leaving unexplored the potential impact of the in-bulk structure of the support. This study demonstrated the influence of in-bulk structure and especially fibers refining degree of 4 kraft papers (SP28, 36, 60, and 80) on the structure, and surface and gas transfer properties of their respective wheat gluten (WG) coated papers (WGP28, 36, 60, and 80). Paper presenting a high fibers refining degree (SP28) exhibited very tight and narrow in bulk fibers network which pre- vented most of the WG-coated layer penetration, maintaining an important WG apparent layer on top of the paper and a small fibers/wheat gluten composite zone inside (WGP28). Such structure gave strong "WG-like" properties to the final coated material with moderate oxygen permeation and high permselectivity (1.50 3 10 211 mol m 22 s 21 Pa 21 and 8.09, respectively for WGP28) whereas the highly impregnated structure of coated papers built on lowly refined papers (SP80, with wide and loose structure) gave coated materials presenting weak "WG-like" properties, supposedly due to a thick composite zone presenting interfacial defects, with higher oxygen permeation and very limited permselectivity (11.90 3 10 211 mol m 22 s 21 Pa 21 and 1.06, respectively for WGP80). V C 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 2848-2858, 2013

Gas transfer properties of wheat gluten (WG) coated paper and their ability to fulfil the requirements in eMAP of fresh parsley were studied. Permeation of gases through WG-paper was demonstrated to be RH-dependent and closely related to structural modification in the WG layer. Formation of micro-cracks was evidenced in dry conditions; but when increasing RH, plasticisation occurs within the protein layer and micro-fractures were reduced until disappearance. This reversible phenomenon allowed the WG-layer to recover its integrity at RH higher than 70%, and the WG character to be expressed in such conditions. When used at 20 degrees C and 80% RH as part of the packaging of parsley, modified atmosphere was created and a steady state of 11 kPa O-2 and 4.5 kPa CO2 was reached after 45 h. In such conditions, the overall quality of parsley leaves remained acceptable during 8 days, with only 28% loss of chlorophyll. (C) 2013 Elsevier Ltd. All rights reserved.

International audience; To overcome the limitations of current trial and error approaches used to design food packaging, a requirement driven approach was adapted from the software and service industries to the field of fresh fruits and vegetable packaging. Based on 5 steps, it relies on the knowledge of produce needs and the use of modeling tools to turn produce requirements into packaging properties before designing the packaging. It was then successfully applied to dimension and design an active packaging, tailor made for optimal preservation of strawberries at 20 degrees C. The solution consisted in a PET punnet providing protection against physical damage and a lid ensuring both gas transfer for optimal atmosphere and release of an active agent acting against mold growth. This active lid was made of wheat gluten proteins containing 2-nonanone that was quickly released only in high RH conditions in an amount equal to the minimal inhibition dose for Botrytis cinerea. Industrial Relevance: Design of packaging for fresh produce such as fruits and vegetables is still mainly based on a trial and error approach (often referred as "pack and pray") that does not ensure conception of an optimal packaging for produce preservation. The non-optimal character of existing packaging is one of the main causes of fresh fruit and vegetable losses along the supply chain. This study proposes an alternative approach to design optimal packaging for fresh and respiring produce: the requirement driven approach. This approach was adapted from the field of software and service industries to the specificity of fresh produce packaging one. It takes into account the needs of the produce (e.g. physical protection, microbial protection or optimal atmosphere for preservation) from the very beginning of the conception process to reduce the risks of inadequacy between the packaging and the produce. In addition to knowledge of the produce physiology and needs, this approach relies on the use of modeling tools to turn produce requirements into packaging properties before designing the packaging. The efficiency of such method was demonstrated through a case study on strawberry packaging. Given the increasing quantity of data available on produce physiology and needs, and the online, free to use and user friendly character of recent MAP modeling tools such as Tailorpack (www.tailorpack.com), generalization of the requirement driven approach proposed in this study could be of major interest for the fresh fruits and vegetable packaging industry. It should help to design optimal packaging for specific produce and thus reduce risk of losses along the supply chain by improving preservation.

IATE Axe 5 : Application intégrée de la connaissance, de l’information et des technologies permettant d’accroître la qualité et la sécurité des aliments Publication Inra prise en compte dans l'analyse bibliométrique des publications scientifiques mondiales sur les Fruits, les Légumes et la Pomme de terre. Période 2000-2012. http://prodinra.inra.fr/record/256699; International audience; Mathematical models are instrumental tools to predict gas (O2 and CO2) evolution in headspaces of Modified Atmosphere Packaging (MAP). Such models simplify the package design steps as they allow engineers to estimate the optimal values of packaging permeability for maintaining the quality and safety of the packed food. However, these models typically require specifying several input parameter values (such as maximal respiration rates) that are obtained from experimental data and are characterized by high uncertainties due to biological variation. Although treating and modelling this uncertainty is essential to ensure the robustness of designed MAPs, this subject has seldom been considered in the literature. In this work, we describe an optimisation system based on a MAP mathematical model that determines optimal permeabilities of packaging, given certain food parameters. To integrate uncertainties in the model while keeping the optimisation computational burden relatively low, we propose to use an approach based on interval analysis rather than the more classical probabilistic approach. The approach has two advantages: it makes a minimal amount of unverified assumption concerning uncertainties, and it requires only a few evaluations of the model. The results of these uncertainty studies are optimal values of permeabilities described by fuzzy sets. This approach was conducted on three case studies: chicory, mushrooms and blueberry. Sensitivity analysis on input parameters in the model MAP was also performed in order to point out that parameter influences are dependent on the considered fruit or vegetable. A comparison of the interval analysis methodology with the probabilistic one (known as Monte Carlo) was then performed and discussed.

International audience; There is a growing trend for governmental efforts to promote health benefits of fresh foods, despite their short shelf life. Beyond respect of the chill chain, modified atmosphere is an efficient way to delay senescence and spoilage without using controversial preservatives compounds. Modified atmosphere packaging (MAP) for fresh produce relies on modification of the atmosphere inside the package in order to extend food shelf life and is achieved by the interplay of two processes: (1) the transfer of gases through the packaging and (2) the respiration of the product. MAP can be achieved by matching the film permeation rate with the respiration rate of respiring products. There is a wealth of published information on MAP but a lack of systematic treatment of the data that can provide information to designers and users on which film to use for particular purposes and targets. This approach is especially important for developing biodegradable packaging because of the limited barrier properties of most of them that could be either turned out into an asset to extend shelf life of respiring foods. Mathematical models have been developed (such as www.tailorpack.com) to design passive MAP. Such numerical tools simplify the package design steps by allowing predicting in advance the required window of packaging permeability for maintaining the quality and safety of the packed food. In addition to the gas permeation properties, the design of biodegradable packaging for fresh foods must take into account numerous other factors such as the cost, availability, potential contaminants of raw materials, process ability, preferences of consumer, waste management constraints, etc. In the EcoBioCap project, knowledge engineering method and tools are designed to store, share and use information regarding packaging material and to solve the dilemma of multi-criteria demands. Databases gathering most of the relevant information as regard fresh producer and packaging material are currently developed and used in connexion with the Tailorpack software. A specific methodology has been developed to query those databases when user's preferences are bipolar (i.e., express both constraints and wishes about the desired result). Results are then completely ordered with respect to these bipolar preferences, giving priority to constraints over wishes. This approach has permitted to build a Decision Support System for designing biodegradable packaging for fresh produces. This decision making tool will be useful for the development of new added-value materials for food packaging application from locally available and poorly valorised solid by-products and liquid effluents.

International audience; This chapter discusses the use of wheat gluten (WG) based materials for food packaging. It presents the two technological processes to prepare WG-based materials and reviews the ways to modulate mechanical and mass transfer properties, with a specific section devoted to WG-based nanocomposites. The chapter also includes a case study of using WG-based materials (paper coated by wheat gluten) as modified atmosphere packaging for fruits and vegetables.

Correspondance: fax: +33 4 6714 4990. E-mail address: c-guillaume@univ-montp2.fr Publication Inra prise en compte dans l'analyse bibliométrique des publications scientifiques mondiales sur les Fruits, les Légumes et la Pomme de terre. Période 2000-2012. http://prodinra.inra.fr/record/256699; International audience; Quality changes of fresh endives were related to packaging condition and development of the internal atmosphere composition. Three packaging conditions were tested at 20C: a macroperforated oriented polypropylene (OPP) pouch considered as "unmodified atmosphere packaging" (UAP) and a low density polyethylene (LDPE) pouch with or without an individual oxygen scavenger sachet to create active or passive modified atmosphere packaging (MAP), respectively. With a steady modified atmosphere composed of 3 and 4.5 kPa of O2 and CO2, respectively, the effect of passive MAP on colour changes in endives was similar to that of UAP. Benefit of MAP of endives was obtained by using an O2 scavenger, i.e. active MAP, that did not change O2 and CO2 partial pressure during the steady state period, compared to passive MAP, but induced a 50% reduction of the transient period. This reduction led to an important delay in greening and browning of endives

Several snake venom secreted phospholipases A2 (sPLA2s) including OS2 exert a variety of pharmacological effects ranging from central neurotoxicity to anti-HIV activity by mechanisms that are not yet fully understood. To conclusively address the role of enzymatic activity and map the key structural elements of OS2 responsible for its pharmacological properties, we have prepared single point OS2 mutants at the catalytic site and large chimeras between OS2 and OS1, a homologous but nontoxic sPLA2. Most importantly, we found that the enzymatic activity of the active site mutant H48Q is 500-fold lower than that of the wild-type protein, while central neurotoxicity is only 16-fold lower, providing convincing evidence that catalytic activity is at most a minor factor that determines central neurotoxicity. The chimera approach has identified the N-terminal region (residues 1-22) of OS2, but not the central one (residues 58-89), as crucial for both enzymatic activity and pharmacological effects. The C-terminal region of OS2 (residues 102-119) was found to be critical for enzymatic activity, but not for central neurotoxicity and anti-HIV activity, allowing us to further dissociate enzymatic activity and pharmacological effects. Finally, direct binding studies with the C-terminal chimera, which poorly binds to phospholipids while it is still neurotoxic, led to the identification of a subset of brain N-type receptors which may be directly involved in central neurotoxicity. UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto Clodomiro Picado (ICP)

The ability of an original pH-reversible treatment of milk to improve rennet gelation was evaluated by rheological measurements on reconstituted skim milk supplemented or not with casein. Samples were acidified at 4°C to pH 5.10 by injection of CO 2 in a laboratory pilot plant (pressure less than 2 MPa) and then depressurised under vacuum. Depressurisation induced the pH to return to its initial value (6.65±0.02) and restored the mineral and protein partition of milk as well as the water solvation, the size diameter and the zeta potential of the casein micelles. After rennet addition, CO 2 -treated milk showed a decrease of the rennet clotting time and an increase of the firming rate compared with a non-treated sample. Moreover, this treatment had a positive effect on the release of glycomacropeptide during enzymatic gelation, suggesting that the rennet accessibility of κ -casein was greater in the CO 2 -treated than in the non-treated sample. The pH-reversible CO 2 acidification greatly activated the rennet gelation of casein-supplemented milk. Indeed, without this treatment, no clotting was observed even 300 min after rennet addition. Therefore, this CO 2 treatment might involve modification of the micellar surface properties in favour of rennet gelation.

Two novel peptides that inhibit the intra-erythrocyte stage of Plasmodium falciparum in vitro were identified in the venom of the Trinidad chevron tarantula, Psalmopoeus cambridgei. Psalmopeotoxin I (PcFK1) is a 33-residue peptide and Psalmopeotoxin II (PcFK2) has 28-amino acid residues; both have three disulfide bridges and belong to the Inhibitor Cystine Knot superfamily. The cDNAs encoding both peptides were cloned, and nucleotide sequence analysis showed that the peptides are synthesized with typical signal peptides and pro-sequences that are cleaved at a basic doublet before secretion of the mature peptides. The IC(5O) of PcFK1 for inhibiting P. falciparum growth was 1.59+/-1.15 microM and that of PcFK2 was 1.15+/-0.95 microM. PcFK1 was adsorbed strongly to uninfected erythrocytes, but PcFK2 was not. Neither peptide has significant hemolytic activity at 10 microM. Electrophysiological recordings in isolated frog and mouse neuromuscular preparations revealed that the peptides (at up to 9.3 microM) do not affect neuromuscular transmission or quantal transmitter release. PcFK1 and PcFK2 do not affect the growth or viability of human epithelial cells, nor do they have any antifungal or antibacterial activity at 20 microM. Thus, PcFK1 and PcFK2 seem to interact specifically with infected erythrocytes. They could therefore be promising tools for antimalaria research and be the basis for the rational development of antimalarial drugs.

An experimental method based on the controlled chymosin-induced kappa-casein hydrolysis of milk was proposed to modify micellar reactivity. Milk samples with a degree of kappa-casein hydrolysis of 19, 35, and 51% were obtained. The physicochemical properties of partially converted casein micelles were determined. The net negative charge of casein micelles was reduced with increasing degree of kappa-casein hydrolysis and a small but significant decrease in hydrodynamic diameter and micellar hydration were noted. Dynamic low amplitude oscillatory rheology was used to monitor the rheological properties of acid milk gels (GDL) made with partially chymosin-hydrolyzed milks in comparison with those of strictly acid and rennet gels. An increase in the gelation pH value was observed with increasing the degree of kappa-casein hydrolysis. The moduli values (G' and G'') reached 2 h after the point of gel were, for all degrees of hydrolysis tested, significantly higher than those of strictly rennet and acid gels. Comparison of changes in delta G'/delta t with time indicated differences in gel formation that could be related to the increased values of G' obtained for acid gel made with chymosin-treated milk. At a given time after gelation (2 h), increasing the degree of kappa-casein hydrolysis in milk led also to an increase in the loss tangent and the serum holding capacity of acid milk gels suggesting a correlation between these two parameters.