posted on 2023-11-20, 18:07authored byJosé J. Ordaz-Ortiz, Yair Cruz-Narváez, Moisés Guerrero-Esperanza, Nayeli L. Romero-García, Anita Arroyo-Silva, Carlos Y. Gómez-Cruz
Vanillin is the main component of vanilla flavor and
is naturally
produced from an orchid. However, due to the high cost and time-intensive
nature of cultivating natural vanilla pods, most of the vanillin is
mainly artificially manufactured. Existing methodologies, such as
isotope ratio mass spectrometry (IRMS) and site-specific natural isotopic
fractionation by nuclear magnetic resonance (SNIF-NMR), are employed
to differentiate natural vanillin from other sources based on carbon
and hydrogen isotope measurements. Nevertheless, these methods have
limitations, as the carbon isotopic ratio can be counterfeited by
adding commercially available enriched vanillin. For this research,
we purified 1 mg of vanillin from pods from various geographical and
botanical sources. We developed a novel method for analyzing 13C/12C and 18O/16O isotopic
ratios of vanillin using direct injection analysis coupled with Fourier
transform ion cyclotron resonance mass spectrometry (FT-ICR-MS). This
innovative approach enables the examination of bulk vanillin carbon
and oxygen isotopic ratios, as well as specific molecular fragments.
By analyzing a characteristic vanillin fragment that provides site-specific 18O/16O isotopic ratio data, we achieved superior
clustering and discrimination of samples based on their botanical
source and geographical origin. Our proposed method holds significant
potential for vanillin authentication and can be performed using a
mere 20 μg of pure vanillin in just 10 min of analysis time.
Subsequent research should focus on acquiring additional vanillin
samples from diverse botanical, geographical, and biosynthetic origins
while exploring various isotopic ratios to further enhance the reproducibility
and reliability of this methodology.