Ingénierie des Agropolymères et Technologies Emergentes

Developing a mechanistic understanding of the impact of food structure and composition on human health has increasingly involved simulating digestion in the upper gastrointestinal tract. These simulations have used a wide range of different conditions that often have very little physiological relevance, and this impedes the meaningful comparison of results. The standardized protocol presented here is based on an international consensus developed by the COST INFOGEST network. The method is designed to be used with standard laboratory equipment and requires limited experience to encourage a wide range of researchers to adopt it. It is a static digestion method that uses constant ratios of meal to digestive fluids and a constant pH for each step of digestion. This makes the method simple to use but not suitable for simulating digestion kinetics. Using this method, food samples are subjected to sequential oral, gastric and intestinal digestion while parameters such as electrolytes, enzymes, bile, dilution, pH and time of digestion are based on available physiological data. This amended and improved digestion method (INFOGEST 2.0) avoids challenges associated with the original method, such as the inclusion of the oral phase and the use of gastric lipase. The method can be used to assess the endpoints resulting from digestion of foods by analyzing the digestion products (e.g., peptides/amino acids, fatty acids, simple sugars) and evaluating the release of micronutrients from the food matrix. The whole protocol can be completed in ~7 d, including ~5 d required for the determination of enzyme activities.

ABSTRACT An edible wheat gluten film was developed and effects of gluten concentration, ethanol concentration (ET) and pH of the film‐forming solution on various film properties were evaluated using Response Surface Methodology. pH and ethanol concentration had strong interactive effects on film opacity, water solubility and water vapor permeability. A simultaneous variation of ethanol concentration and pH between 32.5% ET, pH 4 and 45% ET, pH 2 resulted in homogeneous and transparent film with relatively low water solubility. The lowest water vapor permeability would be expected with 20% ethanol concentration and pH 6. Mechanical properties were mainly affected by gluten concentration and pH. The most resistant film was obtained at high gluten concentration (12.5%) and pH 5.

The green chemistry era has pushed the scientific community to investigate and implement new solvents in phenolic compounds (PC) extraction as alternatives to organic solvents, which are toxic and may be dangerous. Recently, deep eutectic solvents (DES) have been applied as extraction solvents for PC. They have the advantages of biodegradability and ease of handling with very low toxicity. Nevertheless, the extraction process is affected by several factors: affinity between DES and the target compounds, the water content, the mole ratio between DES' starting molecules, the liquid/solid ratio between the DES and sample, and the conditions and extraction method. On the other hand, PC recovery from DES is a challenge because they can establish a strong hydrogen bond network. Alternatively, another possibility is to use DES as solvent extraction as well as formulation medium. In this way, DES can be suitable for cosmetics, pharmaceutical, or food applications.

AIMS: To investigate the relation between the chemical structure and the antimicrobial activity of carvacrol, eugenol, menthol and two synthesized carvacrol derivative compounds: carvacrol methyl ether and carvacryl acetate against bacteria, Escherichia coli, Pseudomonas fluorescens, Staphylococcus aureus, Lactobacillus plantarum, Bacillus subtilis, a yeast Saccharomyces cerevisiae and one fungi Botrytis cinerea. METHODS AND RESULTS: The antimicrobial activity was tested in liquid and vapour phases, by both broth liquid and microatmosphere methods, respectively. The same classification of the compound's antimicrobial efficiency was found with both methods. Eugenol and menthol exhibited a weaker antimicrobial activity than carvacrol, the most hydrophobic compound. Carvacryl acetate and carvacrol methyl ether were not efficient, indicating that the presence of a free hydroxyl group is essential for antimicrobial activity. CONCLUSIONS: The different extents of antimicrobial aroma compounds' efficiency showed that hydrophobicity is an important factor and the presence of a free hydroxyl group and a delocalized system allows proton exchange. SIGNIFICANCE AND IMPACT OF THE STUDY: This study has identified the importance of the hydrophobicity and the chemical structure of phenolic aroma compounds for antimicrobial activity and may contribute to a most rational use of these compounds as antimicrobial agent.

Edible composite films comprised of wheat gluten as the structural matrix and various concentrations of different lipids as the moisture barrier component were tested for water vapour permeability, dispersion in water, opacity and mechanical properties. the effects of lipids on the functional properties of gluten‐based composite films depended on the lipid characteristics and on the interactions between the lipid and the protein structural matrix. Beeswax, a solid and highly hydrophobic lipid, was the most effective lipid for improving moisture barrier properties of films; but these films were opaque, weak and disintegrated easily in water. Combining wheat gluten proteins with a diacetyl tartaric ester of monoglycerides reduced water vapour permeability, increased strength and maintained transparency.

Packaging is an essential element of response to address key challenges of sustainable food consumption on the international scene, which is clearly about minimizing the environmental footprint of packed food. An innovative sustainable packaging aims to address food waste and loss reduction by preserving food quality, as well as food safety issues by preventing food-borne diseases and food chemical contamination. Moreover, it must address the long-term crucial issue of environmentally persistent plastic waste accumulation as well as the saving of oil and food material resources. This paper reviews the major challenges that food packaging must tackle in the near future in order to enter the virtuous loop of circular bio-economy. Some solutions are proposed to address pressing international stakes in terms of food and plastic waste reduction and end-of-life issues of persistent materials. Among potential solutions, production of microbial biodegradable polymers from agro-food waste residues seems a promising route to create an innovative, more resilient, and productive waste-based food packaging economy by decoupling the food packaging industry from fossil feed stocks and permitting nutrients to return to the soil. To respond to the lack of tools and approach to properly design and adapt food packaging to food needs, mathematical simulation, based on modeling of mass transfer and reactions into food/packaging systems are promising tools. The next generation of such modeling and tools should help the food packaging sector to validate usage benefit of new packaging solutions and chose, in a fair and transparent way, the best packaging solution to contribute to the overall decrease of food losses and persistent plastic accumulation.

In the agricultural sector of many European countries, biogas production through anaerobic digestion (AD) is becoming a very fast-growing market necessitating to find novel valorizations routes for digestate.

Data generated by analytical instruments, such as spectrometers, may contain unwanted variation due to measurement mode, sample state and other external physical, chemical and environmental factors. Preprocessing is required so that the property of interest can be predicted correctly. Different correction methods may remove specific types of artefacts while still leaving some effects behind. Using multiple preprocessing in a complementary way can remove the artefacts that would be left behind by using only one technique. This article summarizes the recent developments in new data preprocessing strategies and specifically reviews the emerging ensemble approaches to preprocessing fusion in chemometrics. A demonstration case is also presented. In summary, ensemble preprocessing allows the selection of several techniques and their combinations that, in a complementary way, lead to improved models. Ensemble approaches are not limited to spectral data but can be used in all cases where preprocessing is needed and identification of a single best option is not easily done.

Plant-sourced proteins offer environmental and health benefits, and research increasingly includes them in study formulas. However, plant-based proteins have less of an anabolic effect than animal proteins due to their lower digestibility, lower essential amino acid content (especially leucine), and deficiency in other essential amino acids, such as sulfur amino acids or lysine. Thus, plant amino acids are directed toward oxidation rather than used for muscle protein synthesis. In this review, we evaluate the ability of plant- versus animal-based proteins to help maintain skeletal muscle mass in healthy and especially older people and examine different nutritional strategies for improving the anabolic properties of plant-based proteins. Among these strategies, increasing protein intake has led to a positive acute postprandial muscle protein synthesis response and even positive long-term improvement in lean mass. Increasing the quality of protein intake by improving amino acid composition could also compensate for the lower anabolic potential of plant-based proteins. We evaluated and discussed four nutritional strategies for improving the amino acid composition of plant-based proteins: fortifying plant-based proteins with specific essential amino acids, selective breeding, blending several plant protein sources, and blending plant with animal-based protein sources. These nutritional approaches need to be profoundly examined in older individuals in order to optimize protein intake for this population who require a high-quality food protein intake to mitigate age-related muscle loss.

Agricultural waste is a huge pool of untapped biomass resources that may even represent economic and environmental burdens. They can be converted into bioenergy and bio-based products by cascading conversion processes, within circular economy, and should be considered residual resources. Major challenges are discussed from a transdisciplinary perspective, focused on Europe situation. Environmental and economic consequences of agricultural residue management chains are difficult to assess due to their complexity, seasonality and regionality. Designing multi-criteria decision support tools, applicable at an early-stage of research, is discussed. Improvement of Anaerobic Digestion (AD), one of the most mature conversion technologies, is discussed from a technological point of view and waste feedstock geographical and seasonal variations. Using agricultural residual resources for producing high-value chemicals is a considerable challenge analysed here, taking into account innovative eco-efficient and cost-effective cascading conversion processes (bio-refinery concept). Moreover, the promotion of agricultural residues-based business is discussed through industrial ecology, to promote synergy, on a local basis, between different agricultural and industrial value chains. Finally, to facilitate a holistic approach and optimise materials and knowledge flows management, the connection of stakeholders is discussed to promote cross-sectorial collaboration and resource exchange at appropriate geographic scales.

The polar paradox states that polar antioxidants are more active in bulk lipids than their nonpolar counterparts, whereas nonpolar antioxidants are more effective in oil-in-water emulsion than their polar homologs. However, recent results, showing that not all antioxidants behave in a manner proposed by this hypothesis in oil and emulsion, lead us to revisit the polar paradox and to put forward new concepts, hypotheses, and theories. In bulk oil, new evidences have been brought to demonstrate that the crucial site of oxidation is not the air-oil interface, as postulated by the polar paradox, but association colloids formed with traces of water and surface active molecules such as phospholipids. The role of these association colloids on lipid oxidation and its inhibition by antioxidant is also addressed as well as the complex influence of the hydrophobicity on the ability of antioxidants to protect lipids from oxidation. In oil-in water emulsion, we have covered the recently discovered non linear (or cut-off) influence of the hydrophobicity on antioxidant capacity. For the first time, different mechanisms of action are formulated in details to try to account for this nonlinear effect. As suggested by the great amount of biological studies showing a cut-off effect, this phenomenon could be widespread in dispersed lipid systems including emulsions and liposomes as well as in living systems such as cultured cells. Works on the cut-off effect paves the way for the determination of the critical chain length which corresponds to the threshold beyond which antioxidant capacity suddenly collapses. The systematic search for this new physico-chemical parameter will allow designing novel phenolipids and other amphiphilic antioxidants in a rational fashion. Finally, in both bulk oils and emulsions, we feel that it is now time for a paradigm shift from the polar paradox to the next theories.

Analysis of wine fractions before and after thiolysis confirmed the occurrence in red wine of direct reactions between anthocyanins and tannins established earlier in model solutions. Results showed the presence of two types of structures differing in the linkage position of the anthocyanin moiety. On one hand, detection of malvidin-3-glucoside (Mv3g) among thiolysis products revealed the presence of anthocyanin-derived pigments in which Mv3g is linked by its C-6 or C-8 top. On the other hand, LC/MS analysis allowed the detection of two derivatives tentatively identified as flavenes or a bicyclic condensation products yielded by the reaction of a flavanol monomer (C-6 or C-8 top) with malvidin-3-glucoside (C-4 position). The presence of the corresponding benzylthioethers after thiolysis of the polymeric fractions confirmed that procyanidins are similarly involved in the latter reaction. Besides, MS also allowed the detection of new benzylthioethers of catechin derivatives released after thiolysis of the wine fractions, indicating that in addition to the postulated processes other types of reactions take place in wines. © 2000 Society of Chemical Industry.

Shifting from a linear to a circular economy in the agrifood domain requires innovative business models, including reverse logistics, new visions on customer-supplier relationships, and new forms of organization and marketing strategies at the crossroads of various value chains. This research aims to identify and characterise different types of business models that create value from agricultural waste and by-products via cascading or closing loops. Conceptual and management insights into circular business models are still sparse. In total, 39 cases have been studied that convert agro-waste and by-products into valuable products via a circular economy approach. Semi-structured interviews and on-site visits of six representative cases have been done, and secondary data been collected. Data has been treated with content analysis. Cases are presented according to the type of organisational structure, resources, transformation processes, value propositions, key partners, customers, strategic approaches and innovation. Six types of circular business models are identified and discussed: biogas plant, upcycling entrepreneurship, environmental biorefinery, agricultural cooperative, agropark and support structure. They differ in their way of value creation and organisational form, but strongly depend on partnerships and their capacity to respond to changing external conditions. This study offers the first circular business model typology within the agricultural domain, revealing the interconnectedness of the six different business model types. It provides options for managers in positioning and adapting their business strategies. It highlights the potential of using biomass first for higher added-value products before exploiting it as energy source. Cascading biomass valorisation at a territorial level will increasingly be important for locally cooperating actors within a circular bioeconomy approach.

Twenty years ago, Porter et al. (J. Agric. Food Chem. 1989, 37, 615 - 624) put forward the polar paradox stating among others that apolar antioxidants are more active in emulsified media than their polar homologues. However, some recent results showing that not all antioxidants behave in the manner proposed by this hypothesis led us to investigate the relationship between antioxidant property and hydrophobicity. With a complete homologous series of chlorogenic acid esters (methyl, butyl, octyl, dodecyl, hexadecyl, octadecyl, and eicosyl), we observed in emulsified medium that antioxidant capacity increases as the alkyl chain is lengthened, with a threshold for the dodecyl chain, after which further chain extension leads to a drastic decrease in antioxidant capacity. The antioxidant capacity evaluation in emulsion was possible using a newly developed conjugated autoxidizable triene (CAT) assay, which allows the assessment of both hydrophilic and lipophilic antioxidants. The nonlinear behavior was mainly explained in terms of antioxidant location since it was found from partition analysis that the dodecyl ester presented the lowest concentration in the aqueous phase and also that the quantity of emulsifier drastically changes the partition of antioxidant. In addition, this nonlinear influence was connected to the so-called cutoff effect largely observed in studies using cultured cells. Taken together, these different results allow one to make the proposal of a new scenario of the behavior of phenolic compounds in emulsified systems with special emphasis on the micellization process. Finally, in the CAT system, the polar paradox appeared to be the particular case of a far more global nonlinear effect that was observed here.

Abstract In recent years, a novel medium with similar properties to ionic liquids but with additional advantages regarding cost, environmental impact, and synthesis has been developed: deep eutectic solvents (DESs). These solvents result from the association between an organic salt (ammonium or phosphonium) with a hydrogen‐bond donor such as alcohols, acids, or amides. To date, the availability of green, inexpensive and easy to handle solvents is almost non‐existent. Therefore, DESs currently arouse growing interest in many research fields. This review deals with the major applications of this new family of solvents with a particular focus on lipase‐catalyzed reactions such as hydrolysis, aminolysis, or alcoholysis.

Background: Increasing crop production to feed a growing population has driven the use of mineral fertilizers to ensure nutrients availability and fertility of agricultural soils. After nitrogen, phosphorus (P) is the second most important nutrient for plant growth and productivity. However, P availability in most agricultural soils is often limited because P strongly binds to soil particles and divalent cations forming insoluble P-complexes. Therefore, there is a constant need to sustainably improve soil P availability. This may include, among other strategies, the application of microbial resources specialized in P cycling, such as phosphate solubilizing bacteria (PSB). This P-mediating bacterial component can improve soil biological fertility and crop production, and should be integrated in well-established formulations to enhance availability and efficiency in use of P. This is of importance to P fertilization, including both organic and mineral P such as rock phosphate (RP) aiming to improve its agronomic efficiency within an integrated crop nutrition system where agronomic profitability of P and PSB can synergistically occur. Aim of Review: The purpose of this review is to discuss critically the important contribution of PSB to crop P nutrition in concert with P fertilizers, with a specific focus on RP. We also highlight the need for PSB bioformulations being a sustainable approach to enhance P fertilizer use efficiency and crop production. Key Scientific Concepts of Review: We first recognize the important contribution of PSB to sustain crop production, which requires a rational approach for both screening and evaluation of PSB enabling an accurate assessment of the bacterial effects both alone and in intertwined interaction with plant roots. Furthermore, we propose new research ideas about the development of microbial bioformulations based on PSB with a particular focus on strains exhibiting synergetic effects with RP.

We consider the canonical problem of an array of rods, which act as resonators, placed on an elastic substrate; the substrate being either a thin elastic plate or an elastic half-space. In both cases the flexural plate, or Rayleigh surface, waves in the substrate interact with the resonators to create interesting effects such as effective band-gaps for surface waves or filters that transform surface waves into bulk waves; these effects have parallels in the field of optics where such sub-wavelength resonators create metamaterials in the bulk and metasurfaces at the free surfaces. Here we carefully analyse this canonical problem by extracting the dispersion relations analytically thereby examining the influence of both the flexural and compressional resonances on the propagating wave. For an array of resonators atop an elastic half-space we augment the analysis with numerical simulations. Amongst other effects, we demonstrate the striking effect of a dispersion curve which corresponds to a mode that transitions from Rayleigh wave-like to shear wave-like behaviour and the resultant change in the fields from surface to bulk waves.

Over the last three decades substantial attention has been given to the role of dietary fiber in health and disease, in particular diabetes, cardiovascular disease, intestinal health, and some types of cancer. As a result the food industry started to add back fiber to refined foods and develop fiber rich foods. Scientists suggested that whole grain foods are superior to foods enriched with fibers obtained/synthesized using enzyme treatment, and thermal or chemical processing because the content of bioactive components and micronutrients in whole grain is more abundant. This triggered interest in how to isolate the micronutrient rich aleurone fiber fraction from wheat. Aleurone is a single cell layer at the inner site of the bran. It contains most of the minerals, vitamins, phenolic antioxidants, and lignans of the wheat grain. Novel milling and dry-fractionation techniques have recently allowed for full-scale separation of aleurone cells from the other layers of wheat bran, yielding a fiber rich concentrate which potentially contains many of the "whole grain kernel bioactives," which recently have been used in a variety of studies. The present review highlights available data on aleurone isolation, composition, intestinal physiology, and its metabolism and potential health benefits as well as its use in food.

International audience

For a transition from a linear, ‘take-make-dispose’ economy to a sustainable usage of all constituents of renewable resources in cascading and circular pathways, new business models valorising streams that are currently considered as waste are needed. The aim of this article is to understand critical success and risk factors of eco-innovative business models that contribute to a circular economy via agricultural unavoidable waste or by-products valorisation. 39 cases were studied focusing on agricultural side stream conversion into valuable products. Semi-structured interviews were performed and secondary data collected. Cases were analysed according to types of initiatives, main objectives, resources and valorisation pathways, as well as external and internal factors that have influenced the businesses over time. Following success and risk factor categories are identified: (1) technical and logistic, (2) economic, financial and marketing, (3) organisational and spatial, (4) institutional and legal, (5) environmental, social and cultural. Herein, specific factors for the agricultural sector are innovative conversion technologies, flexible in and out logistics, joint investments in R&D, price competitiveness for bio-based products, partnerships with research organisations, space availability, subsidies, agricultural waste management regulations, local stakeholder involvement and acceptance of bio-based production processes. Insights from this study can help farmers and agribusiness managers by defining and adapting their strategies within their local contexts. They also show that for shifting from linear agro-food chains to a circular system, individual businesses need to evolve towards more dynamic and integrated business models, in which the macro-environment sets the boundary conditions for successful operations.