/ http://www.nantes.inra.fr/
POST DOCTORAL GRANT
The Research Unit of Biopolymer Interaction and Assembly (BIA)
Of the National Institute of Agronomical Research (INRA),
opens a Post Doctoral position (11 months) on the following topic:
Effect of drying rate on the structure and physicochemical properties of seed biopolymers
Context
The developmental phase during the maturation drying is a key step for the physiological quality of seed as well as grain milling properties. The objective of the research area is to obtain a better understanding of effect of the desiccation rate on the end-use value, the physical properties and the survival in the dry state and germinative ability of two models: wheat and pea. This project is inserted in a global understanding on post-harvest treatment (storage effect) and climatic change (hydro-thermal stress). The research programme involves two complementary approaches on seeds and model systems.
Subject
The primary goal of the post-doc project is to investigate the effect of drying rate on the physicochemical properties of biopolymer-based model systems. These models will be based on a combination of proteins and sugars which originates the vitrification phenomena that can be observed in pea seeds and wheat endosperm. A parallel will be made with the changes in calorimetric properties of the glassy matrix in pea seeds upon different drying rates. Starting from hydrated systems, the effect of the isothermal dehydration rate will be investigated on the physico chemical properties and macro and molecular structure of the matrix. State changes and relaxation phenomena associated to the glass transition temperature (Tg) will be examined, as well as structural changes in the proteins during the dehydration (i.e. aggregation, polymerization…). Depending on the macroscopic aspect of materials, the porosity and hardness will be determined. In addition, measurements to assess the molecular mobility (electron spin resonance, NMR) in the matrix will be considered.
The expertise needed will focus on techniques such as thermal analysis (DSC, TGA), spectroscopy (FTIR…), microscopy (SEM), (nano)indentation.
The laboratory
This work will be performed in the “Biopolymer Interaction and Assembly” research unit of INRA, within the INRA research centre of Nantes where all necessary equipment is available (see the web site: http://www.nantes.inra.fr/nantes_eng/les_recherches/biopolymeres). The research unit Biopolymers, Interactions, Assemblies (BIA) focuses its research priorities on the determinism of the quality of food and non food products. Its research aims are: (i) to control the qualitative variability of raw materials and their by-products, (ii) to control the quality of foodstuffs by integrating nutritional recommendations through the improvement of raw materials based on technological innovation, on the one hand, and through the food design itself, on the other. The research will be developed in collaboration with the research unit Physiologie Moléculaire des Semences (Molecular Seed Physiology) in Angers and will be supported by the regionally funded project “Construction et Santé du Végétal” (COSAVE)
Conditions of application and employement
Fellows interested in this position should be open to pluridisciplinary research, have a proper knowledge of polymer physico-chemistry and biological substrate.
The location of the work is Nantes, an attractive city with half a million of people, enjoying a mild climate, in the southern part of Brittany, 1 h from Atlantic coast, 2h from Paris (TGV).
Grant amount: 1850 Euros / month
The candidates interested by this offer are asked to send before 15/01/08:
- a C.V.
- a letter of motivation
- a one-page summary of previous and present scientific activities
- a list of publications and other scientific achievements.
to
Jane Métayer-Parienty, Email:
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Dr Denis LOURDIN
INSTITUT NATIONAL DE LA RECHERCHE AGRONOMIQUE
Rue de la Géraudière. BP 71 627. 44 316 NANTES Cedex 03
Tel + 33 (0)2 40 67 51 47. Fax + 33 (0) 2 40 67 50 66
http://www.nantes.inra.fr/
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