Isotopes Don't Lie, differentiating organic from conventional banana (Musa AAA, Cavendish subgroup) fruits using C and N stable isotopes

With the dramatic increase of organic banana production worldwide, it is essential to be able to monitor compliance with organic specifications. While the detection of pesticide fraud is routinely controlled by detecting pesticide residues in organic bananas, the detection of fertilizer fraud is much more complex. We compared the δ¹³C and δ¹⁵N isotopic values of green bananas from organic and conventional farms at seven sites around the world. In our whole dataset, the δ¹⁵N values of banana fruits ranged between -1.25 and + 8.91‰. In all sites, δ¹⁵N values of organic banana were significantly higher than conventional fruits (mean value of + 5.24‰ and + 2.342‰, respectively). Conversely, the type of fertilization did not significantly alter δ¹³C values. Our results suggest that it is possible, upon arrival in importing countries, to differentiate bananas grown with synthetic fertilizer from those grown with organic fertilizer.