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Abstract: Demonstration of the regional source of a high-quality product is nowadays essential to protect it from commercial transactions and cheatings. In this study, Sr isotopes are proposed as a tool to identify the regional source of a vegetable, on the basis of a combined geochemical investigation on a Coffea Arabica var. Laurina cultivation plot located on th Réunion Island. The Sr isotopic composition (87Sr/86Sr) of the produced coffee beans (called Pointed Bourbon) and of their growing environment, including soils, parent rocks, waters and fertilizers are determined. Flux of Sr in coffee beans is mainly dominated by soil solutions that can be influenced by Sr-rich fertilizers. This influence is however low enough to detect the cultivation soils’ Sr isotopic ratio in the vegetable product, even after roasting. It also allows discrimination of coffees produced on varied geological areas. Measurements performed on the same variety of coffee beans produced in New Caledonia strengthen the demonstration. [ABSTRACT FROM AUTHOR]

Abstract: Coffee grown at high elevations fetches a better price than that grown in lowland regions. This study was aimed at determining whether climatic conditions during bean development affected sensory perception of the coffee beverage and combinations of volatile compounds in green coffee. Green coffee samples from 16 plots representative of the broad range of climatic variations in Réunion Island were compared by sensory analysis. Volatiles were extracted by solid phase micro-extraction and the volatile compounds were analysed by GC–MS. The results revealed that, among the climatic factors, the mean air temperature during seed development greatly influenced the sensory profile. Positive quality attributes such as acidity, fruity character and flavour quality were correlated and typical of coffees produced at cool climates. Two volatile compounds (ethanal and acetone) were identified as indicators of these cool temperatures. Among detected volatiles, most of the alcohols, aldehydes, hydrocarbons and ketones appeared to be positively linked to elevated temperatures and high solar radiation, while the sensory profiles displayed major defects (i.e. green, earthy flavour). Two alcohols (butan-1,3-diol and butan-2,3-diol) were closely correlated with a reduction in aromatic quality, acidity and an increase in earthy and green flavours. We assumed that high temperatures induce accumulation of these compounds in green coffee, and would be detected as off-flavours, even after roasting. Climate change, which generally involves a substantial increase in average temperatures in mountainous tropical regions, could be expected to have a negative impact on coffee quality. [Copyright &y& Elsevier]