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

Our results

Contents
  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

Heating milk seems to favour the development of allergy in infants

The resistance of dietary proteins to digestion forms the basis for food allergy phenomena. Work by scientists in the INRA Science and Technology of Milk and Eggs Research Unit (STLO) in Rennes has incriminated the effect of excessive thermal treatments for an increase in the resistance to digestion of certain dairy proteins, caseins, in infants. These findings may explain the upsurge of cases of milk allergy.

Biberon.. © INRA, MAITRE Christophe

Caseins, major allergens in children

Milk allergy mainly affects young infants following their initial contact with non-human proteins. It is the third most common food allergy in children, after eggs and peanuts, causing 8% of food allergies in those below the age of 15 years. Most of these children are allergic to caseins. These proteins are weakly structured, which renders them more susceptible to the action of enzymes. Therefore, they should be totally degraded during digestion and unable to induce an allergic reaction. The current upsurge in cases of milk allergy, and more specifically casein allergy, is therefore very surprising.

Blame can be placed on the intensity of thermal treatments

The hypothesis advanced by the scientists to explain the resistance of caseins to digestion incriminated the intensity of the thermal treatments applied to formula milks during their manufacture. The heating of milk can lead to the formation of protein aggregates that resist digestion more than the native proteins from which they are derived.
 

An in vitro model for digestion in infants to verify the hypothesis

The INRA scientists designed model, fat-free powdered milks which were subjected to thermal treatments of differing intensities. These reconstituted powders were then passed through an in vitro digestion model mimicking the physiological conditions that prevail in the digestive tract of infants (stomach and duodenum). Analysis of the digestion products of caseins clearly demonstrated an increase in the resistance of caseins to digestion with the powders subjected to the most intense thermal treatments. These results, obtained in model matrices devoid of fat, were then confirmed in more complex foods such as liquid milks.

Références

See also

  • Dupont D., Mandalari G., Molle D., Jardin J., Rolet-Répécaud O., Duboz G., Léonil J., Mills E.N.C. and Mackie A.R. 2010. Food processing increases casein resistance to simulated infant digestion. Mol. Nutr. Food Res., 54, 1677-1689.
  • Dupont D., Boutrou R., Menard O., Jardin J., Tanguy G., Schuck P., Haab B.B. and Leonil J. 2010. Heat treatment of milk during powder manufacture increases casein resistance to simulated infant digestion. Food Dig. 1, 28-39.
  • R. Boutrou, E. Coirre, J. Jardin, J.Léonil. 2010. Phosphorylation and coordination link of mineral inhibit the hydrolysis of the casein (1-25) peptide by intestinal brush-border membrane enzymes. Journal of Agricultural and Food Chemistry, Vol. 58 (13): 7955-7961.
  • R. Boutrou, J. Jardin, A. Blais, D. Tomé and J. Léonil. 2008. Glycosylations of k-casein-derived caseinomacropeptide reduce its accessibility to endo- but not exo- intestinal brush border membrane peptidases. Journal of Agricultural and Food Chemistry, Vol. 56: 8166-8173.