Vanilla planifolia, a flowering epiphytic orchid, is the major natural source of vanilla flavour. Largely used in dairy products, beverages, bakeries and perfume, vanilla flavour is obtained after... Show moreVanilla planifolia, a flowering epiphytic orchid, is the major natural source of vanilla flavour. Largely used in dairy products, beverages, bakeries and perfume, vanilla flavour is obtained after a long process: from eight to nine months after flower pollination, mature pods are harvested and then prepared during about one year in order to release the characteristic vanilla aroma. Nowadays, more than half of vanilla pods world production comes from Madagascar. To face the concurrence, a solution could be to develop higher quality pods. Selection of the most aromatic vanilla plant is then preferred. Nevertheless, amelioration program are facing up to a lack of knowledge in vanilla plant physiology. It is now essential to understand more the physiological and biochemical mechanisms implied in the aromatic production of V. planifolia pods. In this thesis, a metabolomic analysis of vanilla green pods and leaves has been performed by nuclear magnetic resonance. This technique has allowed the qualitative and quantitative analysis of primary (sugar, amino and organic acids__) and secondary metabolites (phenolic compounds__) present in vanilla plant according to various physiological conditions: developing pods, viral infection, inter-accession or seasonal variation. Show less
