Rangées de graines.. © INRA, Elena Schweitzer © Fotolia

Our results

  1. Introduction
  2. Human milk digestion in the preterm infant: impact of technological treatments
  3. Research & Innovation 2017 - For Food and Biobased Products
  4. The way in which proteins aggregate when heated may change their sensitising potency
  5. Enhancing the viability of spray-dried probiotic bacteria by stimulating their stress tolerance
  6. To stick or not to stick? Pulling pili sheds new light on biofilm formation
  7. When biopolymers selfassemble: a balance between energy and entropy.
  8. Mimicking the gastrointestinal digestion in a lab-on-a-chip:the microdigester
  9. How a milk droplet becomes a powder grain
  10. Research & Innovation 2016 - For Food and Bioproducts
  11. A new process for the biorefining of plants
  12. Under the UV light : the bacterial membrane
  13. Reverse engineering or how to rebuild ... bread!
  14. Green Chemistry: a step towards lipid production in yeast
  15. Individually designed neo-enzymes for antibacterial vaccines
  16. Multi-scale mechanical modelling: from the nanometric scale to the macroscopic properties of bread crumb
  17. Minimill: 500 g to assess the milling value of soft wheats
  18. Microbial production of lipids for energy or chemical purposes
  19. The discrete role of ferulic acid in the assembly of lignified cell wall
  20. Eco-design of composites made from wood co-products
  21. Analysis of volatile compounds enables the authentication of a poultry production system
  22. Nanoparticles as capping agents for biopolymers microscopy
  23. Pasteurisation, UHT, microfiltration...All the processes don't affect the nutritional quality of milk in the same way
  24. Integration of expert knowledge applied to cheese ripening
  25. Controlling cheese mass loss during ripening
  26. The shape memory of starch
  27. Research & Innovation 2015 - For Food & Biobased Products
  28. Behaviour of casein micelles during milk filtering operations
  29. Overaccumulation of lipids by the yeast S. cerevisiae for the production of biokerosine
  30. Sequential ventilation in cheese ripening rooms: 50% electrical energy savings
  31. An innovative process to extract bioactive compounds from wheat
  32. Diffusion weighted MRI: a generic tool for the microimaging of lipids in food matrices
  33. Characterization of a major gene of anthocyanin biosynthesis in grape berry
  34. New enzyme activity detectors made from semi-reflective biopolymer nanolayers
  35. Improving our knowledge about the structure of the casein micelle
  36. Heating milk seems to favour the development of allergy in infants
  37. Fun with Shape
  38. Using volatile metabolites in meat products to detect livestock contamination by environmental micropollutants
  39. SensinMouth, when taste makes sense
  40. A decision support system for the fresh fruit and vegetable chain based on a knowledge engineering approach
  41. SOLEIL casts light on the 3D structure of proteins responsible for the stabilisation of storage lipids in oilseed plants
  42. A close-up view of the multi-scale protein assembly process
  43. Controlling the drying of infant dairy products by taking water-constituent interactions into account
  44. Polysccharide nanocrystals to stabilise pickering emulsions
  45. Discovery of new degradative enzymes of plant polysaccharides in the human intestinal microbiome
  46. A durum wheat flour adapted for the production of traditional baguettes
  47. Virtual modelling to guide the construction of « tailored-made » enzymes
  48. How far can we reduce the salt content of cooked meat products?
  49. Diffusion of organic substances in polymer materials: beyond existing scaling laws
  50. Smart Foams : various ways to destroy foams on demand !
  51. Dates, rich in tannins and yet neither bitter nor astringent
  52. Sodium content reduction in food
  53. Research & Innovation 2014

Eco-design of composites made from wood co-products

Taking environmental impact criteria into account in the preliminary design of complete functional units or semi-products is of increasing concern to businesses today. Eco-design implies a compromise between technical performance and environmental profile. This is done by using life cycle indicators such as the Life Cycle Assessment (LCA) and optimisation tools that take multiple objectives into account, both economic and environmental, to establish the “Pareto optimum”. In economic terms, the Pareto optimum is a state in which it is not possible to improve the well-being of an individual without having a negative impact on another. When this concept is transposed to the design of materials and processes, each individual becomes an objective to be reached.

Updated on 06/17/2013
Published on 06/11/2013

Combined uses of polymers and wood co-products

The combined use of co-products from wood processing industries and polymers opens the way to the development of new applications such as “plastic woods” that represent a growing market.  Their use in exterior trim would make it possible to partially replace PVC, whereas when used for outdoor porches and decks, it would eliminate the necessity of chemical treatments used on solid wood in these cases.  These materials are therefore part of a sustainable development approach (substitution of fossil resources with renewable resources), but that nevertheless raise environmental issues: energy balance, end-of-life disposal, etc.

A general eco-design methodology based on a multi-objective optimisation algorithm (the Pareto optimum)

Research carried out by the Biopolymer and Wood Sciences Unit has led to the development of a general eco-design methodology based on a multi-objective optimisation algorithm (the Pareto optimum), and subsequently to the development and validation of a software tool, “Ted”, making it possible to apply the method and to produce new knowledge about the mechanical and environmental performances of composites with lignocellulosic reinforcements.  
“Ted” software makes it possible to treat all types of composites for applications requiring a compromise between several objectives and is thus particularly well adapted to eco-design issues.

The optimisation strategy chosen was to look for the set of Pareto-optimal solutions (Pareto front) within the framework of design objectives.  These solutions are such that we cannot improve one objective without altering at least one other.  The method chosen is known as MOPSO, for "Multi-Objective Particle Swarm Optimisation". Objective functions for mechanical properties (creep and swelling) and the environmental property, limited to non-renewable energy consumption, were established.  Each objective function depends on design variables identified on the basis of an analytical, statistic or qualitative study.  The objective functions are related to each other by shared design variables.

The flexible software tool developed (Ted) allows the user to program objective functions and constraints specific to his or her design problem.  The evolution of the Pareto front is visualised graphically.  At the end of the process, the coordinates of Pareto-optimal solutions are recorded in a text format file. Since the analysis of the Pareto front and the choice of interesting compromise solutions for an industrial application are influenced by technico-economic constraints, all of the optimal solutions are proposed.  If we consider non-renewable energy consumption as the first criterion, favourable compromises are located in the blue zone (fig.), in the central part of the front.

Représentations graphiques du front de Pareto (a et b). © INRA
Représentations graphiques du front de Pareto (a et b) © INRA

The challenge : improving the environmental profile while maintaining technical performance of the eco-composites

To improve the environmental profile while maintaining technical performance, we considered the following two possibilities:  the chemical modification of fibres (one subsidized thesis) and the use of recycled thermoplastic (HDPE) and/or the incorporation of cornstarch (PLA) mixed with HDPE.  The chemical modification of fibres by acetylation makes the fibres hydrophobic and therefore reduces the quantity of thermoplastic used without altering the composite’s resistance to water.  Its anti-swelling ability is directly linked to the intensity of the grafting that then becomes a design variable.  Use of recycled HDPE and/or the incorporation of PLA mixed with HDPE leads to a significant decrease in the environmental impact of the composite.

A new combination of wood and biopolymers was manufactured

For the first time, formulations to replace synthetic plastic with biopolymers were manufactured by an industrial partner specialised in the production of composite wood.  Qualification testing of the product revealed that performances (sustainability) are slightly altered but that the environmental profile is clearly improved.
This work  was part of the projet Eco-Composite granted by the National Resarch Agency (ANR-PRECODD). It put together a company, a technical institute and the Joint Research Unit Wood and Biopolymers sciences, INRA-CNRS-Université Bordeaux 1.

See also

  • Michaud, F., P. Castéra, C. Fernandez and A. Ndiaye (2009). "Meta-heuristic methods applied to the design of wood-plastic composites, with some attention to environmental aspects." Journal of composite material, 43(5): 533-548.
  • Castéra, P., A. Ndiaye, C. Fernandez and F. Michaud (2008). "L'optimisation par essaim particulaire appliquée à la conception de composites à renforts lignocellulosiques." Revue des composites et matériaux avancés,  18(2): 185-190.
  • Ndiaye, A., F. Michaud, P. Castéra and C. Fernandez (2007). Metaheuristic methods applied to the environmentally concious optimization of wood-plastic composite. Twenty-second Technical Conference, Seattle, WA, September 17-19, 2007. CD-ROM(Issue): 11 pp., American Society for Composites.