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International audience; Cheeses exist since ancient times and are still a matter of discovery, as well as a source of innovation. Originally designed to preserve milk, their culture- and tradition-driven technology led to the empirical selection of domesticated microbial consortia. Science has later deciphered, cultivated and characterized the members of such dedicated consortia. Microbial strains can now be selected based on both technological and probiotic criteria. Beyond the traditions and the expected hedonic perceptions, the keystones of the current changes in cheese technology are indeed the way cheeses are made, the way starters are selected and conserved as well as how the cheeses are destructured in the digestive tract, according to specific population. Here we describe our advances in these different research areas and the emerging trends for future. The selection of strains of lactic acid bacteria and of propionibacteria, each combining cheese-making and probiotic skills, leads to the production of functional cheeses, in which the dairy matrix constitutes a protective delivery vehicle for immunomodulatory components. This is illustrated in the context of colitis, i.e. gut inflammation.Cheeses enriched in whey proteins, fermented with selected starters, fulfil the requirements of elderly towards essential aminoacids.Uncoupling the 2 major steps of cheese making, texturing through protein concentration, and flavouring through microbial fermentation, allows quick, safe and sustainable production of “high-tech” cheeses with reduced energy consumption and reduced coproducts production.Incorporation of vegetable proteins, and of microbes able to process them, into the cheese-making process, leads to innovative cheeses with a reduced ecological impact.All these innovations open new avenues for the development of designer cheeses adapted to evolving needs of specific populations and addressing growing ethical concerns.

De nombreux programmes de santé ont essayé d’aider les individus à mettre en œuvre un régime alimentaire pour améliorer leur santé. Ces programmes, principalement axés sur l'éducation et l'information, visaient à lutter contre l'épidémie d'obésité et ses conséquences potentielles sur les troubles de la santé. Nous nous interrogeons sur la manière dont les appareils connectés pourraient constituer une méthode plus efficace pour promouvoir des aliments sains. Ils peuvent être utilisés dans une perspective de marketing social pour mélanger le divertissement virtuel et l'engagement réel à un changement de comportement, comme un régime plus sain pour une meilleure santé., Numerous health programs have tried to make people implement their diet to improve their health. These programs - mainly education and information-oriented - nevertheless sought to fight the epidemic of obesity and its potential outcomes on health disorders. We question how connected devices could provide a more effective method to promote healthy food. They can be used in a social marketing perspective to mix virtual entertainment and real commitment to a behavioural change, such as a healthier diet for a better life.

National audience

INTRODUCTION Propionibacterium freudenreichii is an emergent probiotic bacterium, belonging to dairy propionibacteria, within the group of Actinomycetales, and possessing the GRAS (Generally Recognized As Safe, USA, FDA) and QPS (Qualified Presumption of Safety, EFSA, European Union) status. It is a traditional Swiss-type cheeses starter and an emergent probiotic, exerting several beneficial effects, including anti-inflammatory modulation of gut inflammation. This feature relies on several metabolites and on surface proteins including in particular the surface protein SlpB. METHOD In the present study, we assessed first the impact of proteolytic degradation of SlpB on its immunomodulatory effect on colon epithelial HT-29 cells. Intact P. freudenreichii cells, purified surface layer proteins (SLPs), as well as trypsin-proteolyzed SLPs, were used to stimulate HT-29 cells, in the presence or absence of pro-inflamatory LPS. Cytokines were then quantified to evaluate the inflammatory response. We then investigated the potential of cheese matrix as a delivery vehicle of anti-inflammatory P. freudenreichii MAMP to the colon, by comparing dairy liquids matrices to a solid Swiss-type cheese matrix, using two in vitro digestion models. Integrity of SlpB was monitored using western blotting. RESULTS In this study, we firstly investigated the relevance to avoid SlpB digestive proteolysis, by comparing the effect of i) P. freudenreichii CIRM-BIA 129, ii) its native SLPs, or iii) peptides resulting from SLPs stimulations, with respect to modulation of HT-29 cells response to lipopolysaccharide (LPS) challenge. The anti-inflammatory effect exerted by P. freudenreichii CIRM-BIA 129 and by native surface proteins (SLPs) on HT-29 cells was abolished by digestive proteolysis. This result confirmed the importance to protect immunomodulatory surface proteins from digestive proteolysis in order to allow gut immune system modulation. Thus, we examined the effect of dairy matrices on P. freudenreichii viability and on SlpB integrity during digestion. In comparison with liquid matrices, the cheese matrix provided an enhanced tolerance to digestive stresses and protection of SlpB towards proteolysis, during two in vitro digestion models: static and dynamic. CONCLUSION These in vitro results provide new insights into the matrix effect on P. freudenreichii probiotic functionalities. The cheese matrix offers significant protection against the digestion stresses by enhancing survival, and by protecting surface layer proteins from proteolysis. However, in vivo investigations are necessary to study the matrix effect during digestion, to follow SLPs expression and to evaluate the matrix effect on immunomodulation by P. freudenreichii within the gut. Such data accordingly will allow the development of new functional foods for the delivery of P. freudenreichii to the gastrointestinal tract of humans in the aim to help prevention or treatment of life-style related diseases with an inflammatory component.

Propionibacterium freudenreichii is a beneficial bacterium traditionally used as a cheese-ripening starter and more recently for its probiotic abilities based on the release of beneficial metabolites. In addition to these metabolites (short-chain fatty acids, vitamins, and bifidogenic factor), P. freudenreichii revealed an immunomodulatory effect confirmed in vivo by the ability to protect mice from induced acute colitis. This effect is, however, highly strain-dependent. Local action of metabolites and of immunomodulatory molecules is favoured by the ability of probiotics to adhere to the host cells. This property depends on key surface compounds, still poorly characterized in propionibacteria. We thus investigated the involvement of a specific propionibacterial surface protein in adhesion of the probiotic Propionibacterium freudenreichii to host cells. We compared several strains of Propionibacterium freudenreichii, with respect to adhesion to cultured human intestinal epithelial cells, using a well-established model. We inactivated genes using a previously developed method, based on the integration of a non-replicative plasmid, harbouring a portion of the target gene. We analysed adhesion of the wild type and the mutant strains using fluorescent-assisted flow cytometry and confocal microscopy. We also sought inhibition of adhesion using antibodies directed against surface layer proteins. In the present study, we showed different adhesion rates to cultured human intestinal cells, among strains of P. freudenreichii. The most adhesive one was P. freudenreichii CIRM-BIA 129, which is known to expose surface-layer proteins. We evidenced here the involvement of these proteins in adhesion to cultured human colon cells. We then aimed at deciphering the mechanisms involved in adhesion. Adhesion was inhibited by antibodies raised against SlpB, one of the surface-layer proteins in P. freudenreichii CIRM-BIA 129. Inactivation of the corresponding gene suppressed adhesion, further evidencing the key role of slpB product in cell adhesion. This work confirms the various functions fulfilled by surface-layer proteins, including probiotic/host interactions. It opens new perspectives for the understanding of probiotic determinants in propionibacteria, and for the selection of the most efficient strains within the P. freudenreichii species.

Human studies have clearly demonstrated the beneficial impact of consuming oats on cholesterol levels, however, processing can have a significant influence on functionality, which has not yet been fully addressed., Epidemiological and interventional studies have clearly demonstrated the beneficial impact of consuming oat and oat-based products on serum cholesterol and other markers of cardiovascular disease. The cholesterol-lowering effect of oat is thought to be associated with the β-glucan it contains. However, not all food products containing β-glucan seem to lead to the same health outcome. Overall, highly processed β-glucan sources (where the oat tissue is highly disrupted) appear to be less effective at reducing serum cholesterol, but the reasons are not well understood. Therefore, the mechanisms involved still need further clarification. The purpose of this paper is to review current evidence of the cholesterol-lowering effect of oat in the context of the structure and complexity of the oat matrix. The possibility of a synergistic action and interaction between the oat constituents promoting hypocholesterolaemia is also discussed. A review of the literature suggested that for a similar dose of β-glucan, (1) liquid oat-based foods seem to give more consistent, but moderate reductions in cholesterol than semi-solid or solid foods where the results are more variable; (2) the quantity of β-glucan and the molecular weight at expected consumption levels (∼3 g day–1) play a role in cholesterol reduction; and (3) unrefined β-glucan-rich oat-based foods (where some of the plant tissue remains intact) often appear more efficient at lowering cholesterol than purified β-glucan added as an ingredient.

Une particularité des aliments d’origine végétale est d’être des sources riches et exclusives d’une grande diversité de composés bioactifs qui participent à leurs effets santé. Contrairement aux autres micronutriments (minéraux, vitamines), les phytomicronutriments ne sont pas essentiels pour la croissance et le développement des grandes fonctions de l'organisme. Cependant ces composés constituent des acteurs clés du « bien vieillir en bonne santé ». En effet, un grand nombre d'études d'observation et d'intervention ont montré que certains de ces bioactifs végétaux apportés par l’alimentation (polyphénols, caroténoïdes, glucosinolates, phytostérols) pouvaient contribuer de manière significative à maintenir les grandes fonctions physiologiques et à réduire le risque de maladies chroniques liées au vieillissement.Cependant, il ressort aussi de l'observation qu'il existe des différences substantielles entre les sujets en réponse à des interventions nutritionnelles mettant en jeu des aliments riches en bioactifs végétaux ou des composés purifiés. Cette constatation laisse sous-entendre que certains sous-groupes de population pourraient tirer plus de bénéfice que d'autres de la consommation de produits végétaux. Il est maintenant devenu essentiel de traiter spécifiquement et de façon adéquate la question des facteurs (génétiques, environnementaux) responsables de cette hétérogénéité. En effet, c’est seulement sur la base d’une meilleure connaissance de ces facteurs que de nouvelles stratégies pourront être développées efficacement afin d’optimiser les effets bénéfiques de la consommation d'aliments végétaux pour tout le monde.

Symposium 144/105 - Nutrition Science at a Cross – roadSymposium 144/105 - Nutrition Science at a Cross – road; Up today nutrition science, in Western countries, has been mainly experimented according to the reductionist paradigm. Reductionism is based on the assumption that since reality is too complex to be studied as such it needs to be fragmented into isolated entities that are studied according to the view that the whole is equal to the sum of the part (2 = 1+1) on the basis of a linear cause-effect relationship. As a result foods are considered as only sums of nutrients and calories ; and one nutrient is generally associated with one deregulated metabolism then one chronic disease (e.g., relationship between saturated fats, dyslipidemia and atherosclerosis whereas it is a reducing association). Reductionism can be considered as the main deep cause at the roots of diet-related chronic diseases that are encountered in populations consuming the most fractionated/recombined and refined ultra-processed foods, the ultimate consequence of reductionism. Indeed, if foods are only sums of nutrients why not cracking them in a multitude of nutrients and to recombine them. Nutritional supplements, functional foods and ultra-processed foods are therefore the consequences of our modern reductionist science. They are also based on the assumption that food health potential is based on its composition only.On the contrary, holism views whole foods as more than a sum of nutrients because of synergy of action of nutrients and food matrix effect. Holistic nutrition science defines food health potential as combination of both matrix and compositional effects. Food is more than the only sum of nutrients (2 > 1+1). Matrix effect is crucial because it impacts satiety potential and nutrient bioavailability, both playing a crucial role to maintain a good health. Therefore two foods of identical composition but with a different matrix have not the same health potential.Therefore to fight against the increasing prevalence of diet-related chronic diseases we need today to base more nutrition science on the holistic paradigm. Whereas recombined/refined ultra-processed foods are the fruit of reductionism whole and complex foods participate more of the holistic paradigm which should encourage technologists to less process foods to preserve their matrix, and public authorities to lay emphasis on minimally-processed foods as a basis of a healthy diet.In addition to food science and technology the holistic paradigm may find other important applications in the study of diets on human health. Randomized controlled studies are coming from reductionist and pharmacologist designs, very far from real life, and cannot yield long-term and effective applicable results. Nutrition science is not pharmacology and foods are not drugs: therefore application of holism should prompt nutritionists to carry out intervention studies in complex real life conditions (taking into account all aspects of dietary lifestyles), and not to control only one

IBD constitute a growing public health concern in western countries. Inflammation is a key parameter involved in many non-communicable chronic diseases. Bacteria with anti-inflammatory properties are lacking in dysbiosis accompanying IBD. Selected strains of probiotic bacteria with anti-inflammatory properties accordingly alleviate symptoms and enhance treatment of ulcerative colitis in clinical trials. Such properties are also found in selected strains of dairy starters, including Propionibacterium freudenreichii and Lactobacillus delbrueckii, which are widely ingested. We investigated the possibility to develop a fermented dairy product, combining both starter and probiotic abilities of both lactic acid and propionic acid bacteria, designed to extend remissions in IBD patients.Methods & ResultsWe developed a two-strain P. freudenreichii and L. delbrueckii-fermented experimental pressed cheese using strains previously selected for their anti-inflammatory properties. This cheese was made in fully mastered conditions and contained only the two selected strains. It was consumed daily by mice during five days before induction of acute colitis by trinitrobenzenesulfonic acid (TNBS). Outcomes of colitis induction were then monitored in mice consuming this cheese or a placebo dairy matrix.For the first time, consumption of a designer P. freudenreichii and Lactobacillus delbrueckii pressed cheese was shown to protect mice against experimental colitis, alleviating severity of symptoms, modulating local and systemic inflammation, as well as colonic oxidative stress and epithelial cell damages. As a control, the corresponding sterile dairy matrix failed to afford such protection.ConclusionWe eat more bacteria through daily consumption of fermented dairy products then through functional food supplements. This offers a tremendous level to modulate the digestive tract through the intake of desired bacteria. This work reveals the probiotic potential of a mixture of lactic and propionic selected starters. A “two-in-one” ability is revealed for bacteria able both to produce a fermented dairy product and to modulate inflammation. Such an innovation opens new avenues for the reverse engineering development of anti-inflammatory fermented foods designed for target populations with IBD, and has provided evidences leading to an ongoing pilot clinical study in ulcerative colitis patients.This work was financed by the French National Agency for Research.

Scope. Inflammatory bowel diseases (IBD) constitute a growing public health concern in western countries. Bacteria with anti-inflammatory properties are lacking in the dysbiosis accompanying IBD. Selected strains of probiotic bacteria with anti-inflammatory properties accordingly alleviate symptoms and enhance treatment of ulcerative colitis in clinical trials. Such properties are also found in selected strains of dairy starters such as Propionibacterium freudenreichii. Cheese constitutes an important source of bacteria, which can have beneficial effects, depending on the species or strain. We thus investigated the possibility to develop a fermented dairy product, combining both starter and probiotic abilities of propionic acid bacteria, designed to extend remissions in IBD patients.Methods and results. We developed a single-strain P. freudenreichii-fermented experimental pressed cheese using a strain previously selected for its anti-inflammatory properties. Key immunomodulatory P. freudenreichii surface proteins were expressed within the cheese matrix, as evidenced by in situ proteomics. Consumption of this experimental fermented dairy product protected mice against TNBS-induced colitis, alleviating severity of symptoms, modulating local and systemic inflammation, as well as colonic oxidative stress and epithelial cell damages. As a control, the corresponding sterile dairy matrix failed to afford such protection.Conclusion. This work reveals the probiotic potential of dairy propionibacteria, in the context of fermented dairy products. It opens new perspectives for the reverse engineering development of anti-inflammatory fermented foods designed for target populations with IBD, and has provided evidences leading to an ongoing pilot clinical study in ulcerative colitis patients.

conférence plénièreconférence plénière; Est-il possible de prévenir le diabète de type 2 par la nutrition ?. Le Pied Diabétique

5th International Conference on Food Digestion Rennes, France - 4-6 April 2017 Dear Colleagues, Dear Friends, On behalf of the organizing and scientific committees, I’m really proud to invite you to join us at the 5th International Conference on Food Digestion. This conference is a major event in the field of Food, Nutrition and Health. It is organized in the frame of the INFOGEST research network (www.cost-infogest.eu) whose objective is to “improve the health properties of food by sharing our knowledge on the digestive process”. The first 4 editions of the conference were held in Cesena Italy (2012), Madrid Spain (2013), Wageningen The Netherlands (2014) and Naples Italy (2015). They gathered around 200 experts from academia and industry from more than 30 countries. The team from JRU Science and Technology on Milk and Eggs in Brittany will be delighted to welcome you in Rennes France. The conference will take place at Agrocampus Ouest. Dr Didier Dupont, Chair of Infogest

International audience; The purpose of this study was to examine food choice motives associated with various organic and conventional dietary patterns among 22,366 participants of the NutriNet-Sante study. Dietary intakes were estimated using a food frequency questionnaire. Food choice motives were assessed using a validated 63-item-questionnaire gathered into nine food choice motive dimension scores: "absence of contaminants", "avoidance for environmental reasons", "ethics and environment", "taste", "innovation", "local and traditional production", "price", "health" and "convenience". Five consumers' clusters were identified: "standard conventional food small eaters", "unhealthy conventional food big eaters", "standard organic food small eaters", " green organic food eaters" and "hedonist moderate organic food eaters". Relationships between food choice motive dimension scores and consumers' clusters were assessed using analysis of covariance (ANCOVA) models adjusted for sociodemographic factors. "Green organic food eaters" had the highest mean score for the "health" dimension, while "unhealthy conventional food big eaters" obtained the lowest mean score for the "absence of contaminants" dimension. "Standard organic food small eaters", "green organic food eaters" and "hedonist moderate organic food eaters" had comparable scores for the "taste" dimension. "Unhealthy conventional food big eaters" had the highest mean score for the "price" dimension while "green organic food eaters" had the lowest mean scores for the "innovation" and "convenience" dimensions. These results provide new insights into the food choice motives of diverse consumers' profiles including "green" and "hedonist" eaters.

National audience; Conscients qu’une alimentation déséquilibrée peut être à l’origine d’un nombre important de pathologies chroniques, de nombreux pays lancent des campagnes d’information pour inciter les consommateurs à adopter une alimentation meilleure pour la santé en consommant moins de gras, de sucres et de sel et plus de fruits et légumes. Récemment, des études ont également montré que l’alimentation pouvait être à l’origine de 15 à 30 % des émissions de gaz à effet de serre (GES) des pays développés. La nécessité de limiter les émissions de GES conduit de nombreux experts à recommander des changements de comportements alimentaires et l’adoption de régimes moins impactants sur le plan environnemental. Ces recommandations, qui portent notamment sur la baisse de la consommation de produits d’origine animale, ne sont pas encore intégrées aux campagnes d’information mises en place par la puissance publique en France. Nous avons évalué les coûts et les bénéfices de diverses recommandations alimentaires et nutritionnelles qui prendraient en compte ce double enjeu sanitaire et environnemental. Nos résultats montrent que : le coût d’adoption par les consommateurs varie fortement selon les recommandations envisagées ; les objectifs de réduction des émissions de GES et de santé publique sont généralement compatibles ; la valeur économique des effets sur la santé est généralement bien supérieure à celle des effets de réduction des émissions de GES ; pour bon nombre de recommandations, les politiques d’information des consommateurs présentent un bilan coût-bénéfice favorable suggérant qu’il est pertinent d’intensifier ces campagnes d’information.

Les effets hypotenseurs d’une huile d’olive raffinée enrichie en hydroxytyrosol sont associés à une amélioration de la fonction musculaire lisse dans un modèle de souris atteintes de diabète de type 2. Journées francophones de nutrition (JFN 2016)

Objectives and study: Human milk is the ideal food for neonatal nutrition and optimal growth.When the mother's own milk is unavailable or limited, pasteurized human milk from milk banks ispreferentially administered instead of infant formula, especially for preterm hospitalized neonates.Holder pasteurization (62.5 °C, 30 min) is applied for sanitary reasons but alters human milkcomponents such as enzymes and immunoglobulins. In vitro studies have also shown thatpasteurization of human milk impacts its hydrolysis and disintegration in term newborns (De Oliveiraet al., 2016). Our study aimed at investigating the impact of pasteurization of human milk on itsgastric digestion in preterm infants.-Methods: In vivo study was conducted at Rennes Hospital on preterm infants (n=12) fed by afeeding nasogastric tube each three hours (NCT02112331). Over a six-day sequence, gastric aspirateswere collected twice a day, before and after administration of raw or pasteurized human milk.Samples were collected at 35, 60 or 90 min after meal ingestion. Gastric volume and pH weremeasured. Structural changes of the digesta were evaluated by confocal microscopy and laser lightscattering. In digesta, residual intact proteins left were followed by gel electrophoresis (SDS-PAGE)submitted to densitometry, and lipolysis degree was evaluated by gas and thin layer chromatographyfitted to flame ionization detector.-Results: On average (±SD), infants were 27.5 ± 12.3 days old at the first day of the study. Birthweight was 1.4 ± 0.3 kg and gestational age 29.6 ± 1.0 weeks. Digestive kinetics presented high interand intra-individual variabilities. Regarding proteins, results showed a rapid disappearance of intactcaseins and lactoferrin, but a resistance of alpha-lactalbumin. The contribution of meal gastricemptying or hydrolysis in protein disappearance depended on the protein. Some pre-lipolysis wasdetermined in milk before digestion and it was in overall significantly lower in pasteurized than inraw milk, likely due to the heat-denaturation of endogenous lipases. During gastric digestion thekinetics of lipolysis were not affected by pasteurization (p > 0.05). The lipolysis degree ranged from 6to 20% at 90 min. This relatively limited extent of gastric lipolysis was observed for both raw andpasteurized human milk, and was illustrated by the microscopic observations: some native milk fatglobule structure (hydrophobic core enveloped by an amphiphilic membrane) persisted through thegastric digestion for both raw and pasteurized human milk. Regarding the structure, pasteurizationled to heat-induced protein aggregates in the soluble phase and at the interface of the human milkfat globule membrane, and also impacted the protein aggregation and emulsion disintegrationduring gastric digestion.-Conclusion: This study represents a unique and important dataset on the behavior of pasteurizedversus raw human milk. The gastric digestion is a key step which can further modulate nutrientabsorption and infant nutrition. Digestive hydrolysis may also impact on gut microbiota, a majorcontributor to the development of the intestinal and systemic immune systems in the neonatalperiod. Physiologic and metabolic consequences remain to be investigated.

National audience; L'approche réductionniste est prédominante dans la recherche en nutrition, expliquant les mécanismes à la base de l'action des nutriments et augmentant l'espérance de vie. Pourtant, les pathologies associées à l’alimentation, épidémies d'obésité et de diabète, croissent chaque année, conduisant à une réduction de l’espérance de vie en bonne santé. Les interactions qui sous-tendent la relation nutrition-santé ne peuvent être modélisées sur la base d'une relation de cause à effet linéaire entre un composé et un effet physiologique mais plutôt selon des relations non linéaires multi-causales. Expliquer l'ensemble à partir du particulier par une approche réductionniste est limité. Examiner les questions complexes par une vue holistique avant d'aborder une question spécifique devient nécessaire. Mais les deux approches se renforcent mutuellement. Dans cet article sont examinées les conséquences de l'application d'une approche réductionniste versus holistique sur la recherche en nutrition et, plus généralement sur l’alimentation. Ces réflexions et mes recherches m’ont amené, dans une perspective holistique, à définir les trois règles d’or d’une bonne alimentation protectrice à la fois de la santé, du bien-être animal et de l’environnement

Le délicieux gras saturé a été injustement déconsidéré !

The mechanism of interaction of two oppositely charged macromolecules leading to a liquid-liquid phase separation is called complex coacervation. Examples of complex coacervation between oppositely charged polyelectrolytes are numerous but complex coacervation involving two oppositely charged proteins was only described recently and it results from precise balance of repulsive and attractive interactions between the two proteins1. A better knowledge of the mechanisms of formation and stabilization of such system is essential to design biomaterial with optimized properties such as the encapsulation of bioactives. Here, we investigated the potentiality of two whey proteins, Beta-lactoglobulin (BLG) and Lactoferrin (LF), known for their ability to form complex coacervation2, to spontaneously co-assemble with vitamin B9. Under conditions of LF-BLG coacervation, in contrast to BLG, LF is able to interact with vitamin B9, forming specific nanoparticles3. The ability of such nanoparticles to form coacervates with BLG (B9-LF-BLG coacervates) was further investigated. B9-LF-BLG coacervation was assessed across a range of B9:Proteins mixing ratios and pH conditions by turbidity and phase contrast microscopy. Kinetics of their formation were monitored by light scattering technics. B9 entrapment was evaluated. Storage and time stability of the coacervates were assessed at various temperatures. B9-LF-BLG coacervates were formed in a narrow range of pH, protein concentration and stoichiometry. We evidenced that B9-LF-BLG coacervates exhibited an optimal entrapment of ≈ 10 mg B9/g of proteins. The B9-LF-BLG coacervates were stable over a two weeks storage time. The entrapment efficiency of B9 by the coacervates was found to be similar to that of other encapsulation techniques. Hence the B9-LF-BLG coacervates display useful potentialities as biocarriers for bioactives. They constitute new structured biomaterial based delivery systems with enhanced health benefit to formulate natural and functional ingredient.

The authors are very grateful to the physician and nurses of the Human Nutrition Research Centre of Auvergne and to Patrice Reiling for their technical assistance; International audience; Lycopene (LYC) bioavailability is relatively low and highly variable, because of the influence of several factors. Recent in vitro data have suggested that dietary Ca can impair LYC micellarisation, but there is no evidence whether this can lead to decreased LYC absorption efficiency in humans. Our objective was to assess whether a nutritional dose of Ca impairs dietary LYC bioavailability and to study the mechanism(s) involved. First, in a randomised, two-way cross-over study, ten healthy adults consumed either a test meal that provided 19-mg (all-E)-LYC from tomato paste or the same meal plus 500-mg calcium carbonate as a supplement. Plasma LYC concentration was measured at regular time intervals over 7 h postprandially. In a second approach, an in vitro digestion model was used to assess the effect of increasing Ca doses on LYC micellarisation and on the size and zeta potential of the mixed micelles produced during digestion of a complex food matrix. LYC bioavailability was diminished by 83 % following the addition of Ca in the test meal. In vitro, Ca affected neither LYC micellarisation nor mixed micelle size but it decreased the absolute value of their charge by 39 %. In conclusion, a nutritional dose of Ca can impair dietary LYC bioavailability in healthy humans. This inhibition could be due to the fact that Ca diminishes the electrical charge of micelles. These results call for a thorough assessment of the effects of Ca, or other divalent minerals, on the bioavailability of other carotenoids and lipophilic micronutrients.

La microbiologie du lait et de sa transformation

The nutritional benefits of pomegranate have attracted great scientific interest. The pomegranate, including the pomegranate peel, has been used worldwide for many years as a fruit with medicinal activity, mostly antioxidant properties. Among chronic diseases, osteoporosis, which is associated with bone remodelling impairment leading to progressive bone loss, could eventually benefit from antioxidant compounds because of the involvement of oxidative stress in the pathogenesis of osteopenia. In this study, with in vivo and ex vivo experiments, we investigated whether the consumption of pomegranate peel extract (PGPE) could limit the process of osteopenia. We demonstrated that in ovariectomized (OVX) C57BL/6J mice, PGPE consumption was able to significantly prevent the decrease in bone mineral density (−31.9%; p < 0.001 vs. OVX mice) and bone microarchitecture impairment. Moreover, the exposure of RAW264.7 cells to serum harvested from mice that had been given a PGPE-enriched diet elicited reduced osteoclast differentiation and bone resorption, as shown by the inhibition of the major osteoclast markers. In addition, PGPE appeared to substantially stimulate osteoblastic MC3T3-E1 alkaline phosphatase (ALP) activity at day 7, mineralization at day 21 and the transcription level of osteogenic markers. PGPE may be effective in preventing the bone loss associated with ovariectomy in mice, and offers a promising alternative for the nutritional management of this disease.

Background Breakfast cereals exhibit a wide variability in nutritional quality, and differences are not easily grasped by consumers. A simplified nutritional information system might contribute to help consumers make healthier food choices. A five-category colour label based on the Food Standards Agency Nutrient profiling system (FSA score) has been proposed in France to be implemented on the front-of-pack of foods (the five-colour nutrition label - 5-CNL). Objectives were to evaluate the ability of the 5-CNL to discriminate nutritional quality between types of breakfast cereals, within a category and in equivalent products, as well as its ability to change through product reformulation. Methods Nutritional information was collected through an Internet and supermarket research for N = 433 breakfast cereals (N = 380 complete data included in the analyses). Breakfast cereals were categorized according to common attributes in terms of processing and/or ingredients used. The FSA score and 5-CNL category allocation were computed for each cereal. Nutrient content and FSA score were compared across types of cereals. Distribution within the 5-CNL categories was assessed across types of cereals and for equivalent products. Impact of reformulation (reduction of 5 and 10% in simple sugar, saturated fat and sodium) on the 5-CNL category allocation was compared to original allocation with Bapkhar’s tests of homogeneity of marginal distribution. Results Variability in nutritional quality of breakfast cereals was high, as reflected by the FSA score (range −7- 22 for a theoretical range of −15-40) and the 5-CNL (all five categories represented). The 5-CNL allowed for discrimination across types of cereals, within categories of breakfast cereals and for equivalent products (at least 3 categories of the 5-CNL represented). Reformulation scenarios allowed for significant change in 5-CNL allocation: 5% reduction in sugar lead to a modification of the label for 4.21% of products while a reduction of 10% of sugar, saturated fat and sodium lead to a modification of the label for 19.2% of products. Conclusion The 5-CNL adequately discriminates between breakfast cereals. It would therefore be an adequate tool for consumer information on nutritional quality of foods in the French context. Electronic supplementary material The online version of this article (doi:10.1186/s12889-015-1522-y) contains supplementary material, which is available to authorized users.

Biological and pharmacological activity of natural products workshop. Bone health maintenance: innovative nutritional strategy by polyphenols. 62. International Congress and Annual Meeting of the Society for Medicinal Plant and Natural Product Research

Sustainable management impact on tomato product quality and nutritional/health factors. 13. ISHS Symposium on the Processing Tomato

Présentation oale: Dardevet, Dominique COST FA 1005 Infogest is an action granted by COST in the domain of Food and Agriculture. It will last for 4 years from April 4, 2011. It is coordinated by the French National Institute for Agricultural Research (INRA); International audience; The challenge of translating knowledge on food composition into dietary guidelines that promote health is compounded by the process of food digestion. INFOGEST tackles this issue by promoting research on this topic. The digestive system is highly interconnected with the gut microbiota and immune system. Knowledge on digestion must therefore integrate these additional processes in order to link food composition to the nutritional signals finally sensed by the human organism. This issue can be addressed by a backward strategy identifying relevant metabolic signals produced by humans in response to the ingestion of specific foods. Dairy products are major components of the diet and interact with the gut microbiota and the immune system. Also, inflammation is mechanistically linked to the metabolism of nutrients. As a demonstrator of this backwards strategy, this review therefore identifies gaps in knowledge on the association between dairy product consumption and inflammation. We conducted a systematic review of the literature (Medline, Scopus) and identified >60 human studies using inflammatory markers in relation to the consumption of dairy products. These studies were critically evaluated using the PRISMA checklist and EFSA guidance for the authorization of health claims. An inflammatory score was determined for each reported data set to allow for a quantitative evaluation of the impact of dairy consumption on inflammation. Our analysis indicates that dairy products can modulate inflammation in humans. This effect is, however, blurred by the heterogeneity in study designs, the health status of the subjects under study, the type and dosage of the dairy products, and the inflammatory markers measured. Furthermore, the literature is characterized by a large gap of knowledge on the bioavailability of the nutrients potentially mediating these effects. Future research should better combine food and nutritional sciences to adequately follow the fate of bioactive nutrients along the gastrointestinal and metabolic axes.

to define the nutritional needs and to formulate healthy cereal products from these needs. Such an approach should be done with a sustainability perspective, notably preserving environment and allowing marketing of products affordable for all socio-professional categories, and respectful of the different culture worldwide [6].The new ‘philosophy’ to emphasize behind these issues is to move forward technological processes less deleterious towards natural foods through minimal processing. It is not saying that ultra-processing should be abandoned or is useless: innovation and creativity is very necessary and it is normal that agro-food industry and food scientists need to create new foods, even

Undeniably, technological treatments alter the physical structure of the food matrix and hence its nutritional value, either in a positive or negative way. There is obviously no question of eating cereal grains or legumes without hydrothermal treatment because starch has to be a minimally gelatinized to be digestible

L’impact de la structure de l’aliment sur ses propriétés nutritionnelles est encore mal connu. L’objectif de ce travail était de voir si des gels laitiers de composition identique obtenus par des procédés de gélification différents présentaient des cinétiques de digestion des protéines et de mise à disposition d’acides aminés plasmatiques différentes. A partir d’un lait écrémé traité thermiquement (90°C/10 min), un gel acide et un gel présure de composition identique ont été conçus. Ces deux gels présentent des microstructures similaires (diamètre des pores 0.8 μm) et des propriétés rhéologiques voisines (facteur de perte tan δ identiques). Ces deux matrices ont été données à des mini-porcs adultes équipés de canules duodénale et jéjunale et d’un cathéter sanguin. Il ressort que les cinétiques de digestion des protéines laitières dépendent directement du temps de résidence de ces aliments dans l’estomac, luimême piloté par la structure du gel. Les gels acides présentent un temps de résidence plus court dans l’estomac que les gels présure. Le nombre de peptides identifiés dans la lumière intestinale tout au long des 7h de digestion était 3 fois supérieur pour le gel acide que pour le gel présure (4349 vs 1443). Le gel acide provoque l’apparition d’un pic précoce et massif d’acides aminés essentiels dans le plasma. Le gel présure semble induire plus de satiété que le gel acide. Des données supplémentaires obtenues in vitro et in silico ont permis de mettre en évidence une forte agglomération de particules de caséines dans l’estomac pour le gel présure entrainant un temps de séjour supérieur ainsi qu’une contraction du réseau protéique suivie d’une expulsion de lactosérum (synérèse) provoquant une vidange rapide des protéines sériques., Little is known about the effect of the structure on the nutritional properties of food. The objective of this work was to determine if dairy gels of identical composition but obtained through different gelation process exhibited different protein kinetics of digestion and amino acid release in plasma. Using a heattreated milk (90°C/10 min), an acid and a rennet gel were manufactured. These two gels exhibited similar microstructure (mean pore diameter of 0.8μm) and rheological properties (identical loss factor tan δ). Multi-canulated (duodenum and jejunum) adult mini-pigs bearing blood catheters were fed these matrices. Milk protein kinetics of digestion were directly related to the time of residence of the matrices in the stomach that was driven itself by the gel structure. Acid gels showed a lower time of residence in the stomach than the rennet one. Number of peptides identified in the intestinal lumen throughout the 7h of digestion was 3 times higher for the acid gel (4349 vs 1443). The acid gel caused a fast and sharp increase of essential amino acids in the plasma. Rennet gel induced more satiety than acid ones. Supplementary data obtained in vitro and in silico showed a strong casein particle aggregation in the stomach for rennet gel leading to a higher time of residence and a contraction of the protein network followed by an expulsion of whey (syneresis) causing a rapid gastric emptying of the whey proteins.

Scientific evidence clearly shows that food health potential depends on both its matrix structure (i.e., qualitative food characteristics) and nutrient composition (i.e., quantitative food characteristics). But food structure comes first because, at identical chemical composition, health potential may completely differ depending on food structure [1]. Indeed, this is the food structure parameters e.g., matrix density, particle size, nutrient interactions, starch structure, etc. that will determine nutrient bioavailability, then health effects.

Présentation poster : Lara Cardozo Junior E.; National audience; Yerba-maté (Ilex paraguariensis A.St.-Hil.) est une plante originaire d'Amérique du Sud, traditionnellement consommée comme une boisson stimulante. Différents produits traditionnels (maté, chimarrão, tereré) sont obtenus à partir des feuilles de Yerba-maté et consommées en infusion. Les études sur la composition chimique du maté ont révélé sa richesse en composés phénoliques, principalement des acides caféoylquiniques. La présence simultanée de différents acides mono- et di-caféylquiniques est une particularité de ces produits. La consommation d'aliments riches en composés phénoliques a été associée à un effet bénéfique sur certains facteurs de risque cardiométabolique (pression sanguine, fonction endothéliale, HDL et LDL-cholestérol, résistance à l’insuline). Dans ce contexte, on peut s’interroger sur l’intérêt potentiel de la consommation de Yerba-maté pour la santé cardiovasculaire. Plusieurs études in vitro et in vivo chez l’animal ont montré que les polyphénols présents dans le maté pourraient effectivement exercer des effets biologiques en lien avec la protection cardiovasculaire. Cependant il y a encore peu de données sur les avantages potentiels d’une consommation régulière de Yerba-maté sur la santé cardiovasculaire chez l'homme. Dans ce contexte, notre projet prévoit d’une part, d’évaluer les niveaux et les modes de consommation de Yerba-maté dans la population de la ville de Toledo, Paraná, Brésil et d’autre part, de réaliser une étude d'intervention nutritionnelle chez l’homme pour évaluer les effets d’une consommation de produits traditionnels de maté, avec un contenu standardisé en composés phénoliques, sur des biomarqueurs cliniques du risque cardiovasculaire. Il s’agira d’une étude contrôlée, randomisée et en crossover, réalisée chez des hommes sains présentant des facteurs de risque cardiovasculaire, qui devront consommer pendant un mois un produit de maté, dont la composition en polyphénols aura été caractérisée, ou une boisson contrôle. Outre l’impact sur des biomarqueurs fonctionnels et systémiques de la fonction vasculaire et de l’inflammation, en condition basale et en réponse à un test de charge au glucose, l’étude prévoit aussi d’examiner les effets nutrigénomiques induit par la consommation de maté par une analyse des profils d’expression géniques au niveau des cellules immunitaires circulantes.

invited lecture; National audience; Les produits alimentaires de type grains et graines constituent la base de la pyramide alimentaire pour la majorité de la population mondiale. Les grains et graines incluent les grains de céréales (e.g. blé et maïs) et de pseudo-céréales (e.g. quinoa), les légumineuses (e.g. haricot), les graines oléagineuses et les fruits à coque (e.g. noix et graine de sésame). Contrairement aux légumes et fruits qui sont riches en fibres, vitamines, minéraux et autres composés bioactifs), ils ont la particularité d’être aussi riche en énergie. Cependant, ils contiennent aussi des facteurs anti-nutritionnels comme l’acide phytique. A l’inverse des graines oléagineuses et fruits à coque, les grains doit être processée avant consommation, notamment pour rendre l’amidon plus digestible et pour dégrader certains facteurs anti-nutritionnels qui peuvent limiter l’absorption des minéraux. Toutefois, la tendance a été bien souvent d’appliquer des traitements technologiques trop drastiques, notamment pour les céréales, réduisant leur densité nutritionnelle et donc leur valeur santé (e.g. raffinage excessif des farines). Aujourd’hui, on recherche donc à appliquer des traitements technologiques plus doux (minimal processing) afin de trouver un bon compromis entre améliorer leur digestibilité et conserver leurs composés protecteurs. D’un point de vue santé et nutrition préventive, contrairement aux céréales raffinées, la consommation de céréales complètes a été associée à un risque significativement plus faible de développer l’obésité, le diabète de type 2, les maladies cardiovasculaires et certains cancers digestifs. Quant aux légumineuses, leur consommation devrait être largement plus encouragée car ils ont l’avantage d’être à la fois bon marché et de posséder une haute valeur nutritionnelle (sucres lents, fibres, densité nutritionnelle et potentiel satiateur élevés). Concernant les graines oléagineuses et les fruits à coque, des résultats récents ont montré leur effet protecteur pour la santé, notamment vis-à-vis des maladies cardiovasculaires, lorsque consommés en quantité modérée en raison de leur densité énergétique élevée.

Dairy propionibacteria, mainly Propionibacterium freudenreichii, are consumed in high amounts within cheeses. They are also known as probiotics able to modulate the gut microbiota and the corresponding metabolic activities. Their immunomodulatory properties, analyzed here on human PBMCs, displayed a remarkable variability, depending on the P. freudenreichii strain. Moreover, such modulating properties varied depending on the culture medium considered, i.e. laboratory culture medium versus fermented dairy product. Selected anti-inflammatory strains were further tested in 2 distinct mice experimental colitis models, revealing significant protection and confirming for these cheese starter bacteria (i) probiotic potential and (ii) predictive value of immune-based selection criteria. The role of surface component, including surface exopolysaccharide (EPS) and surface exposed proteins (SEPs), in this modulation, was investigated. We showed that presence of EPS abrogates immunomodulation while presence of key SEPs determines nature and intensity of this modulation. These key SEPs are being identified, as well as the mechanisms leading to their variability. These results open new perspectives for propionibacteria selection aiming at probiotic applications and new mechanistic explanation of their effects on the digestive tract.

Background and objectives.[br/] Dairy propionibacteria are isolated from various ecological niches, including soil, grass, silage, rumen, raw milk and dairy plants, showing great adaptability and robustness. Used as ripening starters in Swiss type cheeses, these food grade bacteria are described as nutraceutical producers and they release into the external medium short chain fatty acids (SCFA), folic acid, cobalamin and the bifidogenic 1,4- dihydroxy-2-naphthoic acid (DHNA). These compounds are known to play a pivotal role in the modulation of intestinal physiology through diet. Considering the pro-apoptotic potential of some of these metabolites, we investigated the potential of dairy products fermented by the main species, Propionibacterium freudenreichii, to prevent colon carcinogenesis. Methods.[br/] We developed a new fermented milk. Taking advantage of milk fractions, high and stable populations of P. freudenreichii were obtained in this product. It was tested in vitro on gastric HGT-1 and colic HT-29 cells with respect to the typical hallmarks of apoptosis. In vivo, the fermented milk was evaluated in piglets with respect to general health parameters and in human microbiota-associated rats, treated or not with dimethylhydrazine (DMH), with respect to intestinal proliferation and apoptosis. Results. Fermented milk induced cell death in both gastric and colon cancer cells. Cellular and molecular characterization of cells dying in response to SCFA treatment revealed cell cycle arrest, drop in intracellular ATP, depolarization of mitochondria, translocation of key apoptosis proteins, processing of caspases and fragmentation of the nucleus. Interestingly, the new fermented milk was shown to potentiate the cytotoxic effect of molecules used in cancer chemotherapy. In accordance, it modulated expression of key apoptotic proteins. In vivo, the fermented milk was evaluated in piglets. Daily oral gavage led to high colic P. freudenreichii populations, to modulation of the intestinal microbiota and modulation of intestinal cytokines. Promotion of piglets’ growth also revealed general probiotic effects of fermented milk. Considering that propionibacteria were metabolically active in the intestine, we further investigated their impact on colon carcinogenesis (induced by dimethylhydrazine, DMH) in human microbiota-associated rats. Consumption of selected strains of propionibacteria resulted in enhanced apoptotic depletion of DMH damaged epithelial cells, yet had no effect on neither proliferation nor apoptosis in healthy rats. Conclusions and perspectives.[br/] These results open new perspectives in the field of colon cancer cells prevention and/or treatment. The synergy with pro-apoptotic chemotherapy molecules suggests that such a fermented product may be proposed as a food supplement to enhance the effects of anticancer treatments.

C’est à la fin des années 1970 qu’émergea l’idée que les protéines alimentaires pouvaient, en plus de leur vocation nutritive, avoir des rôles physiologiques grâce à la présence de peptides bioactifs encryptés dans leur séquence. Les protéines laitières sont une source particulièrement bien dotée en de tels peptides et sont porteuses d’activités aussi diverses que des activités anti-hypertensives, anti-thrombotiques, anti-oxydantes, immunomodulatrices, anti-stress, anti-microbiennes, anti-virales, anti-tumorales et facilitatrices du transport de calcium ou encore de certains oligo-éléments. La littérature fait état d’un nombre impressionnant d’études sur les peptides bioactifs pour leur bénéfice-santé et le potentiel qu’ils représentent dans le développement de nouveaux aliments de prévention/aliment-santé. Il faut cependant différencier les effets physiologiques potentiels appuyés par des études in vitro et ceux réellement démontrés in vivo chez l’animal et chez l’homme. Cet éditorial se focalisera dans des domaines où les enjeux de santé sont importants notamment les risques cardiovasculaires, l’obésité, la défense immunitaire en privilégiant les résultats avec études cliniques. L’introduction très récente de la génomique fonctionnelle au travers des profils d’expressions moléculaires (ARN messagers, protéomes, métabolomes) dans le cadre des études d’interventions nutritionnelles sur les constituants actifs du lait est probablement une des voies les plus prometteuses pour mieux appréhender le mode d’action de ces peptides bioactifs. Par ailleurs ces peptides posent le problème récurrent des critères de choix qui permettraient de mieux évaluer la valeur nutritionnelle des protéines alimentaires qui, malgré une nouvelle définition où le DIAAS1 remplace le PDCAAS2 (voir Actualités), ne tient toujours pas compte du rôle de ces peptides qui interagissent sur les fonctions digestives.

INFOGEST is an international network of institutes carrying out research on food digestion. Here, Dr Didier Dupont, a senior scientist at the French National Institute for Agricultural Research in Rennes, discusses the project’s aims and the challenges presented by a multidisciplinary approach

Nutritional recommendations concern the reduction of the consumption of certain saturated fatty acids (SFA), which are associated with the risk of cardio-vascular diseases, in favour of increased amounts of unsaturated fatty acids (UFA) in the human diet. In this context, adapting the FA profile of high-fat content dairy products such as cheeses is of considerable interest for industrials and consumers. The objectives of this study were i) to produce an experimental UFA-enriched milk by adapting the cows diet (corn silage + grass silage + rapeseed) and to collect control milk in a local dairy plant during winter season (corn silage based diet), ii) to evaluate the possibility of manufacturing mould-ripened soft cheeses, iii) to characterize the physico-chemical and sensory properties of the UFA-enriched and control cheeses. Camembert-type cheeses have been chosen since they are highly appreciated by French consumers and about 108.000 tons are produced each year (CNIEL 2009).These experiments have been performed in the project “AGILAIT” (ANR 06-PNRA-012).

High-throughput sequencing technologies have the potential to decipher genomic diversity at a moderate cost. Propionibacterium freudenreichii is an Actinobacterium used in cheese technology (responsible for aroma and holes in Swiss cheese) and that has probiotic properties (bifidogenic and with anti-inflammatory properties in human and animal). 23 strains of Propionibacterium freudenreichii covering 18 different sequence types out of 46 (Dalmasso et al. AEM 2010) were (i) sequenced by Solexa-Illumina paired-end sequencing and (ii) de novo assembled using Velvet software. Depending on strain, 63 to 166 scaffolds were obtained. These scaffolds were arranged along the reference genome CIRM-BIA1, previously obtained from traditional Sanger sequencing (Falentin et al. PlosOne 2010). For each strain, single nucleotide polymorphism and insertion deletion events were plotted against reference genome. Sequences were automatically annotated (by blastp and pattern matching) on the INRA AGMIAL platform. By bidirectional best-hit, each gene was attributed either to core genome or accessory genome. In some strains, some genes belonging to the accessory genome corresponded with genomic islands and confered peculiar phenotypes (ability to lactose degradation for exemple). In the future, screening of P. freudenreichii (~500 strains) collection on genetic basis at CIRM-BIA biological resource center (Rennes) will help in strain choice for cheese starter and probiotic market.

L’industrie laitière rencontre parfois des problèmes d’instabilité du lait UHT au cours de son stockage. L’instabilité des laits se traduit généralement par une gélification ou par une séparation de phases. Les causes sont multifactorielles (zoologique, enzymatique, physico chimique...). Cette instabilité pourrait venir de la protéolyse des micelles de caséines des laits UHT au cours de leurs stockages. Récemment, il a été démontré que les protéases des cellules somatiques et la plasmine n’avaient pas d’effet sur le phénomène de déstabilisation alors que la protéase AprX d’une souche de P. fluorescens (espèce psychrotrophe la plus retrouvée dans le lait) avait un effet marqué sur la déstabilisation (I.Gaucher, 2008). Ces résultats n’ayant été obtenus qu’avec une seule souche, il était donc essentiel de reproduire ce phénomène de déstabilisation et de le caractériser sur une plus grande gamme de souche du genre Pseudomonas afin de mieux comprendre les mécanismes mis en jeu.Pour cela, six souches du genre Pseudomonas ont été inoculées dans du lait microfiltré (lait épuré au niveau des cellules somatiques et de la flore bactérienne) puis traité thermiquement (140°C/4sec). Après 1 mois de stockage, la déstabilisation était visible. Des agrégats étaient également détectés. En parallèle, nous avons trouvé une augmentation de la taille et de la charge des micelles de caséines, une baisse de l’hydratation micellaire ainsi qu’une augmentation de l’azote non caséinique et de l’azote non protéique pour les laits ensemencés par rapport aux laits témoins. Les résultats obtenus traduisaient bien la protéolyse des micelles de caséines. L’outil spectrométrie de masse va être par la suite utilisé pour permettre de déterminer les peptides issus de ces protéolyses. Nous espérons de cette manière mieux comprendre le mode d’action de ces protéases. Sur les 6 souches, 5 secrètent la protéase aprX. La déstabilisation de ces laits serait donc due à cette protéase thermorésistante au traitement UHT. Le mécanisme proposé est résumé dans la figure 1. Afin de confirmer cette hypothèse, il a été prévu d’injecter une quantité définie de l’enzyme directement dans du lait UHT et d’en apprécier la déstabilisation.

Nutritional recommendations concern the reduction of the consumption of certain saturated fatty acids (SFA), which are associated with the risk of cardio-vascular diseases, in favour of increased amounts of unsaturated fatty acids (UFA) in the human diet. In this context, adapting the FA profile of high-fat content dairy products such as cheeses is of considerable interest for industrials and consumers. The objectives of this study were i) to produce an experimental UFA-enriched milk by adapting the cows diet (corn silage + grass silage + rapeseed) and to collect control milk in a local dairy plant during winter season (corn silage based diet), ii) to evaluate the possibility of manufacturing mould-ripened soft cheeses, iii) to characterize the physico-chemical and sensory properties of the UFA-enriched and control cheeses. Camembert-type cheeses have been chosen since they are highly appreciated by French consumers and about 108.000 tons are produced each year (CNIEL 2009).These experiments have been performed in the project “AGILAIT” (ANR 06-PNRA-012).

Milk and dairy products contain micronutrients such as minerals and vitamins, which contribute to multiple and different vital functions in the organism. The mineral fraction is composed of macroelements (Ca, Mg, Na, K, P, and Cl) and oligoelements (Fe, Cu, Zn, and Se). From a physicochemical point of view, the chemical forms, the associations with other ions or organic molecules, and the location of macroelements such as Ca, Mg, Na, K, P, and Cl in milk are relatively well described and understood. Thus, it is admitted that these macroelements are differently distributed into aqueous and micellar phases of milk, depending on their nature. K, Na, and Cl ions are essentially in the aqueous phase, whereas Ca, P, and Mg are partly bound to the casein micelles. About one third of the Ca, half of the P, and two thirds of the Mg are located in the aqueous phase of milk. Dairy products are more or less rich in these different minerals. In cheeses, mineral content depends mainly on their processing. The Ca content is strongly related to the acidification step. Moreover, if acidification is associated with the draining step, the Ca content in the cheese will be reduced. Thus, the Ca content varies in the following increasing order: milks/fermented milks/fresh cheeses < soft cheeses < semi-hard cheeses < hard cheeses. The chemical forms and associations are less described than those present in milk. Concerning Ca, the formation of insoluble calcium phosphate, carbonate, and lactate is reported in some ripened cheeses. The NaCl content in cheeses depends on the salting of the curd. From a nutritional point of view, it is largely admitted that milk and dairy products are important sources of Ca, Mg, Zn, and Se. The vitamin fraction of milk and dairy products is composed of lipophilic (A, D, E, and K) and hydrophilic (B(1), B(2), B(3), B(5), B(6), B(8), B(9), B(12), and C) vitamins. Because of their hydrophobic properties, the lipophilic vitamins are mainly in the milk fat fraction (cream, butter). The hydrophilic vitamins are in the aqueous phase of milk. For one part of these vitamins, the concentrations described in the literature are not always homogenous and sometimes not in accordance between them; these discrepancies are due to the difficulty of the sample preparation and the use of appropriate methods for their quantification. However, there is no doubt of the significant contribution of milk and dairy products to the intake of vitamins. Milk and dairy are considered essential sources for vitamins. Key teaching points: Milk and dairy products are unique micronutrient combinations with recognized health benefits. The concentration, chemical forms, and location of different minerals are relatively well known and described. For example, Ca is present in dairy products in different forms: free, associated with citrate, inorganic and organic phosphates, and free fatty acids. Milk and dairy products are excellent sources of Ca, P, Mg, Zn, and Se. The concentration of vitamins in milk and dairy products is variable and depends on several factors such as biosynthesis, animal feeding, physicochemical conditions (heat, light, O(2), oxidant agents), and analytical methods for their determinations. Vitamins A, D, E, and K are mainly located in the lipid phase and vitamins of group B and C in the aqueous phase. Milk and dairy products are excellent sources of vitamins A, B(1), B(2), and B(12).

Les produits laitiers et leur microflore Comment maîtriser la conception de produits laitiers fermentés ?. Doctorama 2011 Université de Nancy

Milk and dairy products contain micronutrients such as minerals and vitamins, which contribute to multiple and different vital functions in the organism. The mineral fraction is composed of macroelements (Ca, Mg, Na, K, P, and Cl) and oligoelements (Fe, Cu, Zn, and Se). From a physicochemical point of view, the chemical forms, the associations with other ions or organic molecules, and the location of macroelements such as Ca, Mg, Na, K, P, and Cl in milk are relatively well described and understood. Thus, it is admitted that these macroelements are differently distributed into aqueous and micellar phases of milk, depending on their nature. K, Na, and Cl ions are essentially in the aqueous phase, whereas Ca, P, and Mg are partly bound to the casein micelles. About one third of the Ca, half of the P, and two thirds of the Mg are located in the aqueous phase of milk. Dairy products are more or less rich in these different minerals. In cheeses, mineral content depends mainly on their processing. The Ca content is strongly related to the acidification step. Moreover, if acidification is associated with the draining step, the Ca content in the cheese will be reduced. Thus, the Ca content varies in the following increasing order: milks/fermented milks/fresh cheeses < soft cheeses < semi-hard cheeses < hard cheeses. The chemical forms and associations are less described than those present in milk. Concerning Ca, the formation of insoluble calcium phosphate, carbonate, and lactate is reported in some ripened cheeses. The NaCl content in cheeses depends on the salting of the curd. From a nutritional point of view, it is largely admitted that milk and dairy products are important sources of Ca, Mg, Zn, and Se. The vitamin fraction of milk and dairy products is composed of lipophilic (A, D, E, and K) and hydrophilic (B(1), B(2), B(3), B(5), B(6), B(8), B(9), B(12), and C) vitamins. Because of their hydrophobic properties, the lipophilic vitamins are mainly in the milk fat fraction (cream, butter). The hydrophilic vitamins are in the aqueous phase of milk. For one part of these vitamins, the concentrations described in the literature are not always homogenous and sometimes not in accordance between them; these discrepancies are due to the difficulty of the sample preparation and the use of appropriate methods for their quantification. However, there is no doubt of the significant contribution of milk and dairy products to the intake of vitamins. Milk and dairy are considered essential sources for vitamins. Key teaching points: Milk and dairy products are unique micronutrient combinations with recognized health benefits. The concentration, chemical forms, and location of different minerals are relatively well known and described. For example, Ca is present in dairy products in different forms: free, associated with citrate, inorganic and organic phosphates, and free fatty acids. Milk and dairy products are excellent sources of Ca, P, Mg, Zn, and Se. The concentration of vitamins in milk and dairy products is variable and depends on several factors such as biosynthesis, animal feeding, physicochemical conditions (heat, light, O(2), oxidant agents), and analytical methods for their determinations. Vitamins A, D, E, and K are mainly located in the lipid phase and vitamins of group B and C in the aqueous phase. Milk and dairy products are excellent sources of vitamins A, B(1), B(2), and B(12).

Lipolysis plays an important role in the formation of cheese flavor. In Emmental cheese, the main part of lipolysis has been associated with the presence of Propionibacterium freudenreichii, a species used as a ripening culture. Our aim was to identify the most probable lipolytic esterase(s) involved in cheese lipolysis by P. freudenreichii. Since cheese lipolysis mainly occurs during P. freudenreichii growth, we hypothesized that P. freudenreichii possesses secreted lipolytic esterase(s). For 12 putative esterase genes previously identified from the genome of P. freudenreichii CIRM1, the level of expression was quantified by real-time reverse transcriptase (RT)-PCR, and the subcellular localization of esterases was predicted in silico. The esterase activity in extracellular and intracellular extracts of P. freudenreichii was characterized by zymography, and the extracellular esterases were identified by mass spectrometry. Finally, the best candidate was overexpressed in the same strain. All of the 12 genes encoding putative esterases were expressed. Esterase PF#279 was predicted to be secreted in the medium, PF#774 to be surface exposed, and the 10 remaining putative esterases to be intracellular. Zymography revealed that esterase activities in culture supernatant differed from the ones detected in intracellular extracts. PF#279 was identified as the sole esterase present in culture supernatant. Transformed P. freudenreichii CIRM1 clones overexpressing PF#279 showed 5 to 8 times more lipolytic activity on milk fat than the wild-type strain. Combining in silico, biochemical, and genetic approaches, we showed that PF#279 is the sole secreted esterase in P. freudenreichii and is active on milk fat. Therefore, it is likely a key component in cheese lipolysis by P. freudenreichii.

P. freudenreichii (PF) is a Gram + species, with the GRAS (Generally Recognized As Safe) status in the USA and a Qualified Presumption of Safety (QPS) status in Europe. It is widely consumed by humans because it is an essential ripening culture in Swiss type cheeses (Emmental, Leerdammer®…), and also as a probiotic in food supplement (Propio-Fidus®). Recently, PF was shown to produce a (1→3, 1→2)-β-D-glucan polysaccharide. A single gene (named gtf) is responsible for the biosynthesis of this surface polysaccharide, that has been immunodetected for 30% of the 100 strains of PF tested. Here we investigated the role(s) of this β-D-glucan.

Propionibacterium freudenreichii is essential as ripening culture in Swiss-type cheese manufacture and is also considered for its probiotic use. The type strain of this species, P. freudenreichii subsp shermanii CIRM 1 (CIP 103027 or ATCC 9614), was sequenced using a whole genome shotgun strategy. The whole genome was sequenced with an elevenfold coverage. The circular chromosome of 2.7 Mb has a GC-content of 67 % and contains 34 loci corresponding to integrase sequences. IS sequences cover 3.5 % of the genome. The automatic and manual annotation, based on homology and conserved domain research has been done for the complete genome. The annotation revealed (1) the genetic basis of hardiness: sequences involved in immunity against phages, genes belonging to metabolism of different carbon and nitrogen sources, genes encoding enzymes of the vitamins and amino acids synthesis, genes involved in the management of polyphosphate and glycogen storage, several copies of chaperones, genes encoding proteins coping with oxidative stresses (2) genes responsible for aroma compound synthesis: Wood-Werkman pathway forming propionic and acetic acids, esterase/lipase involved in the formation of free fatty acids and esters, pathways of branched chain amino acids degradation resulting in the formation of branched chain volatile fatty acids (3) genes potentially involved in probiotic activity: complete biosynthesis pathway for the bifidogenic compound, a high number of surface proteins present in other probiotic bacteria and involved in the interaction with the host. The perspectives opened by post genomic research for cheese technology and health applications of P. freudenreichii will be discussed.

International audience; La convention sur la diversité biologique souligne le rôle important qu'ont joué les pratiques des sociétés dites "traditionnelles" dans l'utilisation de leur environnement naturel et le maintien de sa biodiversité, et encourage leur application à plus grande échelle. Comment mettre en place des filières équitables autour des ressources forestières en impliquant les sociétés locales de manière à ce qu'elles valorisent elles-mêmes leurs savoirs et savoir-faire sur la nature ? En s'appuyant sur de nombreux exemples, l'article envisage les questions d'ordre éthique, social, environnemental, législatif, technologique et économique, que soulève cette démarche.