Stable isotope composition of cocoa beans of different geographical origin

Abstract

The isotopic profile (δ(13) C, δ(15) N, δ(18) O, δ(2) H, δ(34) S) was used to characterise a wide selection of cocoa beans from different renowned production areas (Africa, Asia, Central and South America). The factors most influencing the isotopic signatures of cocoa beans were climate and altitude for δ(13) C and the isotopic composition of precipitation water for δ(18) O and δ(2) H, whereas δ(15) N and δ(34) S were primarily affected by geology and fertilisation practises. Multi-isotopic analysis was shown to be sufficiently effective in determining the geographical origin of cocoa beans, and combining it with Canonical Discriminant Analysis led to more than 80% of samples being correctly reclassified. Copyright © 2016 John Wiley& Sons, Ltd.

Geographic authentication of the traditional Chinese medicine Atractylodes macrocephala Koidz. (Baizhu) using stable isotope and multielement analyses

“…Compared with the δ 13 C, δ 15 N and δ 34 S values, the δ 2 H and δ 18 O values were not as useful in discriminating between Baizhu samples from Zhejiang and other provinces, as no significant differences were found in most cases. In addition, although correlation between δ 2 H and δ 18 O values has often been found in agro‐products such as olive oil, cocoa beans and coffee, no strong correlation between them was observed in the Baizhu samples examined in this study.…”

“…Whereas the δ 13 C, δ 2 H and δ 18 O values of agro‐products can be attributed to climatic and geographic conditions such as temperature, sunlight, rainfall, altitude and latitude, the δ 15 N values can reflect the soil conditions and local agricultural practices, especially the types of fertilizers applied; the δ 34 S values are also affected by soil sulfate and fertilization (e.g. through the application of ammonium sulfate) . Since synthetic fertilizers have δ 15 N values close to that of atmospheric nitrogen (0‰), and organic fertilizers exhibit higher δ 15 N values (+1 to 37‰), crops grown using synthetic fertilizer generally have lower δ 15 N values than those grown with organic fertilizers .…”

Traceability, authenticity and sustainability of cocoa and chocolate products: a challenge for the chocolate industry

“…The combination of stable isotope ratios of oxygen (d 18 O), hydrogen (d 2 H) and sulfur (d 34 S) with carbon (d 13 C) and nitrogen (d 15 N) was tested as a traceability tool on a wide selection of cocoa beans of different geographical origin (fifty-three samples from Africa, Asia, Central and South America) (Perini et al 2016). For statistical evaluation, the samples were grouped into five different macroareas.…”

Variabilidad de δ13C y δ15N en suelo y hojarasca de cacao en El Oro, Ecuador

“…Los promedios mínimos del isotopo de δ 13 C en la hojarasca por tipo de cacao se obtuvieron en Inceptisol (CCN51, -29.86%±1.57; Nacional, -29.36%±0.77), valores muy similares a los obtenidos por Tezara et al (2016) en hojas vivas de cacao (-29.21%±0.2). El mayor promedio del isotopo de δ 13 C, fueron muy similares en Alf isol (CCN51, -27.21%±0.74) y Entisol (Nacional, -27.80%±1.30), ubicadas en áreas de mayor radiación solar, con respeto a las f incas localizadas en Inceptisol y cuyos valores están dentro de los niveles isotópico obtenidos por Perini et al (2016) Cuadro 3. Media de δ 13 C y δ 15 N de suelos cultivados con cacao.…”

“…En Ecuador, son pocos los trabajos publicados sobre las relaciones isotópicas de δ 13 C y δ 15 N como los realizados por Paul et al (2008) y Rhoades et al (2000) en suelos de la cordillera de los Andes. En el caso del cacao, las investigaciones realizadas por Perini et al (2016) y Tezara et al (2016) en hojas y semillas respetivamente, permitieron conformar un perf il isotópico del origen geográf ico del cacao ecuatoriano. Por lo anterior, este trabajo propuso evaluar las variaciones de los δ 13 C y δ 15 N, determinadas en el suelo y la hojarasca, entre CCN5 y Nacional, localizados en tres órdenes de suelo en la provincia de El Oro.…”