Publications by authors named "Romain Jeantet"

The main objective of this study was to assess the ability of the NEar Real Digestive Tract (NERDT), a computer-controlled biomimetic in vitro digestion system that considers the biomechanics of the stomach, to reproduce physiologically relevant features of skimmed milk gastric digestion. A second objective was to evaluate the influence of pepsin on the gastric coagulation and emptying of milk proteins from experiments performed with and without pepsin. A mass balance model over the stomach, assuming a perfectly stirred reactor behaviour, has been developed.

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Understanding how shear affects whey protein stability is crucial to deal with typical industrial issues occurring at the bulk solution/surface interface, such as fouling during heat treatments. However, at the state of the art, this effect remains unclear, contrary to that of temperature. This article presents a novel strategy to study the impact of shear rate and concentration on the accumulation of whey protein surficial deposits.

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The purpose of this study was to improve understanding of the structural and functional property changes that milk-protein concentrates undergo during production, particularly how the manufacturing route (heat treatment position and intensity), standardization (in osmosed water or ultrafiltrate permeate) and formulation (casein:whey protein (Cas:WP) ratio) influence the physico-chemical characteristics-hygroscopicity, particle size, sphericity, density and evolution of browning during storage. To obtain a comprehensive understanding of the parameters responsible for the distinctive characteristics of different powders, a multifactorial approach was adopted. Hygroscopicity depended mainly on the standardizing solution and to a lesser extent the Cas:WP ratio.

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Dairy ingredients with highly concentrated protein contents are high added value products with expanding market. The manufacture of such ingredients includes a succession of unit operations of which heat treatment is a key step to guarantee the microbial safety, that induces major changes in protein structures and thus ingredients functionalities. However, due to an incomplete understanding of phenomena taking place at high protein concentrations, shedding light on their mechanisms is a scientific challenge as well as an industrial need.

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Dairy powders are mainly produced by droplet spray drying, an articulated process that enables the manufacture of high added-value goods with a long shelf life and well-preserved functional properties. Despite the recent advances, a full understanding of the mechanisms occurring at the droplet scale in drying towers and, consequently, of the impact of process parameters and processed fluid characteristics on the powder properties is far from being achieved. In the wake of previous studies based on a laboratory scale approach, in this work, we provided a global picture of the drying in droplets of dairy protein mixes, i.

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Nowadays, in vitro digestion models have received growing interest in recent years to track the digestive fate of foods in the gastrointestinal tract. A major challenge in the development of more physiologically relevant in vitro gastric models is to simulate realistic gastric emptying. In this study, an advanced dynamic in vitro human gastric system was investigated for its potential in achieving the above.

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Propionibacterium freudenreichii is a beneficial food-grade actinobacterium, widely implemented, and thus consumed, in various food products. As the main application, P. freudenreichii is used as a cheese-ripening starter, mostly in hard type cheeses.

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Infant formulas (IFs) are used as substitutes for human milk and are mostly based on cow milk proteins. For sustainability reasons, animal protein alternatives in food are increasingly being considered, as plant proteins offer interesting nutritional and functional benefits for the development of innovative IFs. This study aimed to assess how a partial substitution (50%) of dairy proteins with faba bean and pea proteins influenced the digestibility of IFs under simulated dynamic in vitro digestion, which were set up to mimic infant digestion.

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Infant formulas (IFs) are the key nutritional source for infants who cannot be breastfed. There is currently a growing interest in these sensitive products in order to control their quality and to design their composition with regard to nutritional balance. In a context of sustainable development and increasing growth of the world population, it seems essential to search for alternative to animal protein in food today.

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Propionibacterium freudenreichii is a beneficial bacterium widely used in food as a probiotic and as a cheese-ripening starter. In these different applications, it is produced, dried, and stored before being used. Both freeze-drying and spray-drying were considered for this purpose.

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The article presents a proteomic data set generated by a comparative analysis of the proteomes of comparing the CIRM-BIA 129 and CIRM-BIA 1025 strains. The two strains were cultivated until the beginning of the stationary phase in a chemical defined medium (MMO), and in this medium in the presence of NaCl, with or without glycine betaine. Whole-cell proteins were extracted, trypsinolyzed and analyzed by nano LC-MS/MS, prior to identification and classification by function using the X!Tandem pipeline software and the proteomic data from NCBI.

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is a beneficial bacterium with documented effects on the gut microbiota and on inflammation. Its presence within the animal and human intestinal microbiota was correlated with immunomodulatory effects, mediated by both propionibacterial surface components and by secreted metabolites. It is widely implemented, both in the manufacture of fermented dairy products such as Swiss-type cheeses, and in the production of probiotic food complements, under the form of freeze-dried powders.

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is a beneficial bacterium, used both as a probiotic and as a cheese starter. Large-scale production of is required to meet growing consumers' demand. Production, drying and storage must be optimized, in order to guarantee high viability within powders.

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The evaporation of colloidal solutions is frequently observed in nature and in everyday life. The investigation of the mechanisms taking place during the desiccation of biological fluids is currently a scientific challenge with potential biomedical and industrial applications. In the last few decades, seminal works have been performed mostly on dried droplets of saliva, urine and plasma.

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Propionibacterium freudenreichii is a beneficial bacterium used as a cheese starter and as a probiotic. Indeed, selected strains of P. freudenreichii combine both technological and health-promoting abilities.

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This review deals with beneficial bacteria, with a focus on lactobacilli, propionibacteria, and bifidobacteria. As being recognized as beneficial bacteria, they are consumed as probiotics in various food products. Some may also be used as starters in food fermentation.

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is a beneficial bacterium, used as a cheese starter, which presents versatile probiotic properties. These properties are strain-dependent. We hypothesized they may also be delivery vehicle-dependent.

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BL23 has a recognized probiotic potential, which includes immune modulation, protection toward induced colitis, toward induced colon cancer and toward dissemination of pathogens. In , as well as in other probiotics, both probiotic and technological abilities are highly dependent (1) on the substrate used to grow bacteria and (2) on the process used to dry and store this biomass. Production and storage of probiotics, at a reasonable financial and environmental cost, becomes a crucial challenge.

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The drying of complex fluids provides a powerful insight into phenomena that take place on time and length scales not normally accessible. An important feature of complex fluids, colloidal dispersions and polymer solutions is their high sensitivity to weak external actions. Thus, the drying of complex fluids involves a large number of physical and chemical processes.

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Protective carriers that encapsulate probiotics in spray drying could improve the survival ratio of dried cells through different mechanisms. Unveiling the protective mechanism of each carrier will contribute to a rational design of high performance carrier formulation. This study utilized single droplet drying (SDD) technique to investigate the effects of calcium cation in varied carrier formulation.

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The swelling of polyelectrolyte hydrogels usually depends on the pH, and if the pH is high enough degradation can occur. A microindentation device was developed to dynamically test these processes in whey protein isolate hydrogels at alkaline pH 7⁻14. At low alkaline pH the shear modulus decreases during swelling, consistent with rubber elasticity theory, yet when chemical degradation occurs at pH ≥ 11.

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Probiotic bacteria have been reported to confer benefits on hosts when delivered in an adequate dose. Spray-drying is expected to produce dried and microencapsulated probiotic products due to its low production cost and high energy efficiency. The bottleneck in probiotic application addresses the thermal and dehydration-related inactivation of bacteria during process.

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Unlabelled: Propionibacterium freudenreichii is used as a cheese-ripening starter and as a probiotic. Its reported physiological effects at the gut level, including modulation of bifidobacteria, colon epithelial cell proliferation and apoptosis, and intestinal inflammation, rely on active metabolism in situ Survival and activity are thus key factors determining its efficacy, creating stress adaptation and tolerance bottlenecks for probiotic applications. Growth media and growth conditions determine tolerance acquisition.

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The drying of milk concentrate droplets usually leads to specific particle morphology influencing their properties and their functionality. Understanding how the final shape of the particle is formed therefore represents a key issue for industrial applications. In this study, a new approach to the investigation of droplet-particle conversion is proposed.

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