2.4. Commercial honey samples analysis using SCIRA method
All d13C‰ determination were performed on Continue-Flowing isotopic ratio mass spectrometer (CF-IRMS), 20-20H from Sercon (Cheshire, UK). The whole procedure for SCIRA analysis was the same as that of AOAC998.12 method. In brief, 2 lL of honey or
syrup, or 2.8 mg of protein was sealed into 6 Â 4 mm tin capsules for d13C‰ determination according to one standard olive oil (1.5 lL in one capsule, d13C‰std = À28.51‰ ± 0.16‰). After finish- ing the analysis of one batch of samples, d13C‰ value for each sam- ple was calculated and printed out automatically.