Several abiotic factors influence the chemical composition of essential oils. Understanding these factors is an important step in developing quality products that meet market demands. This research work aims to study the chemical composition of the essential oils of ylang-ylang (Cananga odorata, forma genuina) according to the maturity of flowers. The volatile compounds of ylang-ylang flowers from Reunion Island were extracted by hydrodistillation and the samples were analyzed by high resolution gas chromatography coupled with mass spectrometry (GC-MS) allowing for the identification of 70 volatile compounds. The chemical composition of the essential oils extracted from the flowers at 5 different stages of development varies both qualitatively and quantitatively. The volatile compounds observed belong to 4 chemical groups which are esters, alcohols, terpenes, and ether-oxides. The synthesis of light oxygenated compounds is largely the predominant chemical subgroup in all stages of development. Their relative content is considerably increased during flower ripening with a peak concentration in stage 4 (SD4). The highest concentrations of non-terpene esters and heavy oxygenated compounds are found in stages 1 (SD1) and (SD5), respectively, while no chemical subgroup is dominant in the intermediate stages 2 (SD2) and (SD3). The dynamics of volatile compounds have also been studied. This study established that the stage of development of ylang-ylang flowers significantly influences the dynamics of volatile compounds in the extracted essential oils. Total oxygenated compounds that are highly odoriferous in essential oils increase progressively and significantly with flower maturity, unlike hydrocarbon terpenes, which are less valuable in terms of their contribution to the fragrance and following opposite kinetics; suggesting that odoriferous properties increase with the development of the flower, with a higher intensity at SD4.

L’île Rodrigues, district autonome de la République de Maurice, est riche de spécialités régionales dont le gouvernement souhaite tirer parti pour relancer le secteur agricole. En particulier, le minuscule « ti piment » est réputé pour son piquant et sa saveur spécifique. Mais sa renommée est affectée par une perte de typicité (hybridations non contrôlées). Mélangé de facto avec d’autres piments, il est valorisé en condiments par des transformatrices entre lesquelles la concurrence se fait de plus en plus rude, faute de débouchés sur Rodrigues même. Peu structurée, la filière peine en effet à satisfaire les exigences du marché mauricien en termes de quantité et de qualité. Le présent article discute ainsi de l’intérêt et des conditions de la création d’un label de qualité pour mieux valoriser ce piment, à la lumière de ses spécificités et de l’organisation actuelle de la filière.

This study examines the effects of flower storage duration and harvest time on the yield and evolution of the volatile composition of ylang-ylang (Cananga odorata forma genuina) essential oil. Oils were obtained from flowers by hydrodistillation immediately or after storage (4 h, 8 h, 24 h and 30 h) to investigate the effect of storage duration and from flowers picked at different schedules (07:00 a.m., 11:00 a.m. and 03:00 p.m.) to investigate the effect of the time of flower harvesting. The ylang-ylang oils were by analyzed by GC–MS. Storage duration had no significant effect on yield up to 8 h, whereas significant decreases occurred after 24 and 30 h. The amount of aromatic compounds decreased markedly with storage, from 73.66% in fresh petals to 57.02% after prolonged storage. Harvest time also influenced the distribution of oxygenated compounds, terpene hydrocarbons and several key volatiles. Overall, oils distilled within 0–8 h after harvest and obtained from flowers collected at 07:00 a.m. or 3:00 p.m. exhibited superior yields and chemical profiles compared with delayed distillation or midday harvest (11:00 a.m.). These results underline the importance of rapid processing and optimized harvest timing to preserve oxygenated fractions and essential-oil quality.