The objective of MAP’OPT project is to explain, quantify and model the effects of modified atmospheres according to packaging film type. Interactions between determining factors and their effects on the effectiveness of MAP will be evaluated. In parallel, methods will be assessed to characterise the effect of gas on food properties. The main factors that will be studied include the characteristics of films, gas composition, their diffusion properties, headspace volume and the weight of the food product. The nature of microorganisms and their respiratory metabolism (aerobic, anaerobic, microaerophilic) are also key factors in this project. Only non-respiring food products will be studied. Impact of gas composition in the headspace on spoilage mechanisms as oxidation will be evaluated. The input data of this project include the available and/or published data on the microbial behaviour under modified atmospheres and on the specific effects of each gas, already acquired knowledge on the gas diffusion through the film or between the headspace and the food product and the laws that govern the diffusion of gases. A general schematic diagramme of the model will be validated and the necessary data for defining the parameters of the models will be collected. The underlying assumptions of the model will be validated: laws of gas diffusion and models on the effects of gas on microbial growth curves. Based on new, acquired and existing data, we will construct models that can assess microbial behaviour according to film type and gas composition of the modified atmosphere.This project is expected to lead to a quantitative approach for optimising barriers properties of packaging films and modified atmospheres composition to ensure better food quality. According to the type of food product and knowledge of the microflora that limits its shelf life, this project aims to determine the parameters to be estimated to optimise the gas mixture and the choice of film. Based on the developed models, the volume of the food package can also be optimized. The Sym'Previus data intergration system will be completed in order to capitalize the new data which will be input in this project. A new database will be designed to modelise the knowledge on the gas diffusion through the film or between the headspace and the food product, and on the impact of gas on bacterial behaviour. Consequently, the Sym'Pevius domain onthology will be complemented to take into account the new knowledge. This project gathers expertises in mass transfer, physical characteristics of food, in packaging, microbiology, biostatistics, quantitative modelling and Bayesian statistitcs and Bayesian networks. The projet has to supply to the scientific community with criteria for the development of new packaging contributing to the safety of food and to the sustainable development.

Food spoilage leads to significant wastes and losses, and is an important economic issue in food industry. In the case of meat, a large part of spoilage is the consequence of bacterial growth and subsequent metabolic activities causing organoleptic spoilage of the final product (defects in texture, color, odor, or aspect), leading finally to products that are lost because they do not fit the quality standards. In addition, meat production chain requires energy, water and cost consuming operations (i.e. animal breeding, slaughtering, and transformation and storage which are usually performed at low temperature). Therefore meat product spoilage that appears at the end of the process or during shelf life affects the whole production chain performances as well as the sustainability label of the meat sector. The objective of the project is to reduce food losses by predicting, early in the production process, the onset of bacterial spoilage during storage in order to propose decision-support tools for directing process. Pork and poultry meat, the two main meats consumed in France will be studied. The economic impact of losses of these products will be assessed. Dynamics of bacterial communities will be monitored during processing steps (from primary cuts to end products at use-by-date and beyond) and various descriptors of spoilage will be measured. The natural variability between batches and that associated with production processes will be considered. Data will be used to identify accurate spoilage markers and to compute innovative mathematical models for predicting spoilage occurrence as a function of the initial composition of the microbiota (diversity and abundance) and some abiotic parameters (storage temperature, modified atmosphere packaging). The models will be validated on meat products, including the economic aspect in order to propose decision-support tools for the food producers.

In recent years, use of new technologies has attracted attention from the food industry due to the increase in consumer demand for minimally processed food products (mild pasteurization) by preserving their nutritional and sensorial properties. The objective of the project is the control of pathogenic and spoilage microorganisms in food products by a rational use of the oxydoreduction potential (Eh). Eh modification will be used to allow the sanitary and quality in different types of food products. It has been already proved that Eh modification (mainly reducing) has a positive impact on the aromatic, rheological and textural properties of food. Access for food operators to a new controlled factor, Eh, will permit in interactions with environmental parameters like pH, aw, temperature, acids to optimize the shelf life of products. The project will also be in the context of food systems with low environmental impact. Food-redox can impact at a better control of energetic consumption in thermal treatment used to stabilize foods and at less withdraw of products from economics actors (operators, distributors) by allowing optimized formulations of foodstuff. Food-Redox might increase the shelf-life by a better control of microbiological safety and the quality of the production, and consequently might reduce the logistic costs. Taking into consideration this context, this project offers several opportunities: to reinforce the competitiveness of the food companies, to reinforce the safety of food and to develop of sustainable methods of production, preservation and handling of agri-food products. The goal of the Food-Redox project is to provide an overview of the microbial cellular response of foodborne and spoilage bacteria to stress (pH, acid, or thermal) under conditions of redox controlled in view of better control these micro-organisms in food. A more comprehensive study on the impact of Eh on the physiology of micro-organisms contaminating food has never been made so far. The work plan integrate research and modelling phase of the effect of Eh on the re-growth of Lactococcus lactis, Listeria monocytogenes, Bacillus cereus after acid or thermal stresses and a validation phase conducted on a selection of foods (cheese, dairy desserts, meat products, sauces, salads) based on bacterial species targeted and stress studied. This program combines 6 academic research laboratories, 4 Agro-industrial Institutes, one company leader in industrial gases, one French dairy council and 2 SME companies, closely involved in the development of processes to control Eh. The Agro-industrial institutes will implement testing at a pilot scale. A scientific based analysis on the possibility to use Eh in new strategies for the control of the microbial contaminations in food products will be available for industry. Scientific communication and technical valorisation of project will be structured by the general committee, the French dairy council and in interaction with the joint national technological network "Expertise on determination of food products microbial shelf life", qualified by the French Ministry of Agriculture in August 2007.

The objectives of the FLUOPATH project are 1) to find new biomarkers (promoeters that induce the expression of genes of interest) coupled to a fluorescent biosensor allowing to acquire new knowledge in bacterial cell physiology related to the impact of technological disturbances inducing stresses. The study will be focused on the growth, survival and virulence of two pathogens in dairy products (milk, diluted cheese and if possible solid cheese) and 2) to use this knowledge combined with the knowledge present in the scientific literature to improve the models for predicting the microbiological risk in dairy products. The pathogens considered will be L. monocytogenes and B. cereus. The matrices considered will be liquid milk as well as model diluted and undiluted cheese (gelified matrix). New models based on the use at the scale of the single cell and the whole population of biomarkers will be developed to predict growth, resistance and virulence (invasive capacity for L. monocytogenes and entry into sporulation and toxin production for B. cereus) to stress while taking into account cellular variability. A precise quantification of the impact of stressful industrial conditions will be carried out on bacterial responses at the cellular level: probability of single cell / whole poulation growth, survival, toxin production, spore formation, invasive capacity. The challenge is to design and validate in food matrices bacterial biomarkers of phenotypes of interest in risk assessment in order to incorporate the intensity of biomarker response into exposure assessment models.

Meat and seafood products are highly perishable foodstuffs, the preservation of which is crucial. Indeed, a bad preservation of these products may lead to important hygienic and safety risks as well as considerable economic loss, a situation that is particularly true for novel products. The utilisation of protective cultures in order to limit these risks is proposed since several years but is still not in common use, partially because a lack of knowledge of microbial ecosystems of these products. The partners of the French network FLOREPRO decided to share their know-how and scientific knowledge on one hand, and their various expertise about food on the other hand, in order to increase the knowledge of meat and seafood products and on the impact of protective cultures on these ecosystems and on the quality of the products. Our aim is thus to provide a sound scientific based information on the benefit that the utilisation of protective cultures may represent in the production of meat/fish foodstuffs. The project is divided into three tasks: - an as exhaustive as possible characterisation of the ecosystem of height selected products (meat and seafood) by the up to date most performing method, 16S rDNA pyrosequencing of the bacterial DNA present on these products, at the time of production and after the use by date. This task also encompasses the selection of putative spoiler micro-organisms from those products; - set up and sharing of model matrices and sensory analysis in order to reproduce spoilage and to prove the spoiling properties of the strains selected from the first task; - evaluation of the impact of already available protective cultures on spoilage, sensorial quality, and global ecosystem of the products we propose to study. The partners of this project are academics, agro institutes and one SME which was a pioneer in the commercialisation of protective cultures. Other industries, SMEs with no financial support, joined the project to furnish the foodstuffs to be analysed. Know-how, expertise and missions of the partners are complementary and about meat/fish products. The foodstuffs we selected are representative of a large panel of origins (beef, veal, poultry, fish, shellfish) and processes (ground, diced cubes, fillets, peeled) and concern novel products for which knowledge about their ecosystem and sanitary quality is scarce.